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                                                                     Exhibit 4.2

                                     FORM OF

                          FIRST SUPPLEMENTAL INDENTURE

                                      among

                                TOM BROWN, INC.,

                             as Issuer and Guarantor

                       TOM BROWN RESOURCES FUNDING CORP.,

                              as Subsidiary Issuer

                                       and

                         U.S. BANK NATIONAL ASSOCIATION,

                                   as Trustee

                         Dated as of September 16, 2003

                                       to

                             SUBORDINATED INDENTURES

                         Dated as of September 16, 2003

                                 --------------



                                  225,000 UNITS

                                  consisting of

   $115,200,000 Aggregate Principal Amount of 7.25% Senior Subordinated Notes
                    due September 15, 2013 of Tom Brown, Inc.

                                       and

   $109,800,000 Aggregate Principal Amount of 7.25% Senior Subordinated Notes
           due September 15, 2013 of Tom Brown Resources Funding Corp.

================================================================================
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                                TABLE OF CONTENTS

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                                    ARTICLE I

                                 NOTES AND UNITS

Section 1.1.   Designation of Notes and Units; Form, Dating and Terms............................................2
Section 1.2.   Execution and Authentication......................................................................6
Section 1.3.   Registrar and Paying Agent........................................................................7
Section 1.4.   Paying Agent to Hold Money in Trust...............................................................7
Section 1.5.   Holder Lists......................................................................................8
Section 1.6.   Mutilated, Destroyed, Lost or Stolen Notes and Units..............................................8
Section 1.7.   Outstanding Notes and Units.......................................................................9
Section 1.8.   Temporary Notes and Units.........................................................................9
Section 1.9.   Cancellation.....................................................................................10
Section 1.10.  Payment of Interest; Defaulted Interest..........................................................10
Section 1.11.  Computation of Interest..........................................................................11
Section 1.12.  CUSIP and ISIN Numbers...........................................................................11
Section 1.13.  Redemption and Repurchase........................................................................12
Section 1.14.  Conversion.......................................................................................12
Section 1.15.  Maturity.........................................................................................12
Section 1.16.  Parent Securities................................................................................12
Section 1.17.  Other Terms of Parent Notes, Subsidiary Notes and Units..........................................12

                                   ARTICLE II

                      AMENDMENTS TO THE ORIGINAL INDENTURES

Section 2.1.   Amendments Applicable Only to the Parent Notes, the Subsidiary Notes and the Units...............12
Section 2.2.   Definitions and other Provisions of General Application..........................................13
Section 2.3.   Covenants........................................................................................45
Section 2.4.   Successor Company................................................................................71
Section 2.5.   Redemption.......................................................................................72
Section 2.6.   Remedies.........................................................................................76
Section 2.7.   Trustee..........................................................................................83
Section 2.8.   Defeasance and Covenant Defeasance...............................................................90
Section 2.9.   Amendments.......................................................................................94
Section 2.10.  Subordination of Notes...........................................................................97
Section 2.11.  Parent Guarantee................................................................................105
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                                   ARTICLE III

                                  MISCELLANEOUS

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Section 3.1.   Integral Part...................................................................................107
Section 3.2.   General Definitions.............................................................................107
Section 3.3.   Adoption, Ratification and Confirmation.........................................................107
Section 3.4.   Counterparts....................................................................................107
Section 3.5.   Benefits of Indenture...........................................................................107
Section 3.6.   Governing Law...................................................................................108
Section 3.7.   Notices.........................................................................................108
Section 3.8.   When Notes or Units Disregarded.................................................................109
Section 3.9.   No Recourse Against Others......................................................................109
Section 3.10.  Waiver of Immunities............................................................................109
Section 3.11.  Consent to Jurisdiction; Appointment of Agent for Service of Process; Judgment Currency.........110

Exhibit A      Form of Parent Note
Exhibit B      Form of Subsidiary Note
Exhibit C      Form of Parent Guarantee
Exhibit D      Form of Unit
Exhibit E      Form of Supplemental Indenture to Add Subsidiary Guarantors

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      FIRST SUPPLEMENTAL INDENTURE, dated as of September 16, 2003 (the
"Indenture"), among TOM BROWN, INC., a corporation duly organized and existing
under the laws of the State of Delaware (the "Parent"), having its principal
office at 555 Seventeenth Street, Suite 1850, Denver, Colorado 80202, TOM BROWN
RESOURCES FUNDING CORP., an unlimited company organized under the laws of Nova
Scotia, Canada having its principal office at 736 8th Avenue, SW, 7th Floor,
Calgary, Alberta, Canada T2P 3H2 (the "Subsidiary Issuer") and U.S. BANK
NATIONAL ASSOCIATION, a national banking association, as trustee (the
"Trustee").

                RECITALS OF THE PARENT AND THE SUBSIDIARY ISSUER

      The Parent has heretofore executed and delivered to the Trustee an
Indenture, dated as of September 16, 2003 relating to its subordinated debt
securities (the "Original Parent Indenture"), providing for the issuance from
time to time of one or more series of the Parents' subordinated debt Securities.

      The Subsidiary Issuer has heretofore executed and delivered to the Trustee
an Indenture, dated as of September 16, 2003 relating to its subordinated debt
securities (the "Original Subsidiary Issuer Indenture" and, together with the
Original Parent Indenture, the "Original Indentures," and, as each shall be
amended and supplemented by this First Supplemental Indenture, the "Indenture"),
providing for the issuance from time to time of one or more series of the
Subsidiary Issuer's subordinated debt Securities.

      Section 901(7) of each of the Original Indentures provides that the Parent
or the Subsidiary Issuer, as applicable, and the Trustee may from time to time
enter into one or more indentures supplemental thereto to establish the form or
terms of Securities of a new series.

      Sections 901(2) and 901(3) of each of the Original Indentures permit the
execution of supplemental indentures without the consent of any Holders to add
to the covenants of the Parent or the Subsidiary Issuer, as applicable, for the
benefit of, and to add any additional Events of Default with respect to, all or
any series of Securities.

      Section 901(5) of each of the Original Indentures permits the execution of
supplemental indentures without the consent of any Holders to add to, change or
eliminate any of the provisions of the Indenture with respect to all or any
series of Securities, provided that, among other things, such addition, change
or elimination does not apply to any outstanding Security of any series created
prior to the execution of such supplemental indenture.

      Section 301 of each of the Original Indentures provides that the Company
may enter into supplemental indentures to establish the form, terms and
provisions of a series of Securities issued pursuant to the Indenture.

      Sections 301(19) and 301(20) of each of the Original Indentures permit
such supplemental indentures to add or to change the covenants and Events of
Default that apply to Securities of the series to be issued.

      Section 301(22) of each of the Original Indentures permits such
supplemental indenture to determine whether the Securities of the series to be
issued will be issued together with other securities as units.


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      The Parent has duly authorized the issuance of its 7.25% Senior
Subordinated Notes due September 15, 2013 (the "Parent Notes"), and to provide
therefor the Parent has duly authorized the execution and delivery of this
Indenture.

      The Subsidiary Issuer has duly authorized the issuance of its 7.25% Senior
Subordinated Notes due September 15, 2013 (the "Subsidiary Notes" and, together
with the Parent Notes, the "Notes"), and to provide therefor the Subsidiary
Issuer has duly authorized the execution and delivery of this Indenture.

      The Parent has duly authorized the unconditional guarantee (the "Parent
Guarantee") of the Subsidiary Issuer's obligations under the Subsidiary Notes
and all the obligations of the Subsidiary issuer as set forth in this Indenture.

      The Parent and the Subsidiary Issuer have duly authorized the creation of
units (the "Units"), each Unit consisting, subject to the Section 802, of $512
aggregate principal amount of Parent Notes and $488 aggregate principal amount
of Subsidiary Notes.

      This Indenture is subject to the provisions of the Trust Indenture Act of
1939, as amended, that are required to be part of this Indenture and shall, to
the extent applicable, be governed by such provisions.

      All things necessary have been done to make the Parent Notes, the
Subsidiary Notes, the Parent Guarantee and the Units, each when duly issued,
executed and delivered by the Parent and/or the Subsidiary Issuer, as the case
may be, and authenticated as described herein, the valid obligations of the
Parent and/or the Subsidiary Issuer, as the case may be, and to make this
Indenture a valid agreement of the Parent and the Subsidiary Issuer, in
accordance with its terms.

      Each party agrees as follows for the benefit of the other parties and for
the equal and ratable benefit of the Holders of Units.

                       ----------------------------------

                                   ARTICLE I

                                 NOTES AND UNITS

      SECTION 1.1. DESIGNATION OF NOTES AND UNITS; FORM, DATING AND TERMS

      (A) These shall be designated series of Securities designated (i) 7.25%
Senior Subordinated Notes due September 15, 2003 of the Parent (the "Parent
Notes"), (ii) 7.25% Senior Subordinated Notes due September 15, 2003 of the
Subsidiary Issuer (the "Subsidiary Notes") and (iii) "Units" consisting of
Parent Notes and Subsidiary Notes. Each Unit shall initially consist, subject to
Section 802, of $512 principal amount of Parent Notes and $488 principal amount
of Subsidiary Notes. The aggregate principal amount of Notes and Units that may
be authenticated and delivered under this Indenture is unlimited.

      Each Holder of Units shall be deemed to be the Holder, for each Unit held
by such Holder, of $512 principal amount of Parent Notes and $488 principal
amount of Subsidiary


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Notes, upon which principal of, premium, if any, and interest on (and, in the
case of the Subsidiary Notes, Additional Amounts, if any) is payable to such
Holder on the dates and in the manner provided in the Parent Notes, the
Subsidiary Notes and in this Indenture.

      The Parent and the Subsidiary Issuer on the Issue Date shall initially
issue, and the Trustee shall initially authenticate and deliver, for original
issue, 250,000 Units consisting of an aggregate of $115,200,000 principal amount
of Parent Notes and $109,800,000 principal amount of Subsidiary Notes. The
Parent and the Subsidiary Issuer may issue, from time to time in compliance with
the provisions of this Indenture, including, without limitation, the covenants
set forth in Article Ten hereof, an unlimited amount of Additional Units
consisting of Additional Parent Notes and the Additional Subsidiary Notes having
identical terms and conditions as the Parent Notes and Subsidiary Notes issued
on the Issue Date; provided that so long as the Subsidiary Issuer is the obligor
under the Subsidiary Notes and is organized under the laws of a province of
Canada, no such Additional Units may be issued within five years prior to the
Stated Maturity of the Subsidiary Notes. Furthermore, Notes and Units may be
authenticated and delivered upon registration or transfer, or in lieu of, other
Notes and Units pursuant to Section 1.6, Section 1.7, Section 1007 or in
connection with an Asset Disposition Offer pursuant to Section 1009 or a Change
of Control Offer pursuant to Section 1017.

      With respect to the issuance of any Additional Notes and/or Additional
Units, the Parent and/or the Subsidiary Issuer, as the case may be, shall set
forth in a resolution of each of its Board of Directors and in an Officer's
Certificate, the following information: (1) the aggregate principal amount of
such Additional Notes and Additional Units to be authenticated and delivered
pursuant to this Indenture, (2) the issue price and the issue date of such
Additional Notes and Additional Units, including, with respect to any Additional
Notes, the date from which interest shall accrue and (3) a representation that
the Parent and the Subsidiary Issuer are each in compliance with the covenants
set forth in Article Ten.

      The Units and any Additional Units shall be considered collectively as a
single class for all purposes of this Indenture. Holders of the Units and
Additional Units will vote and consent together on all matters to which such
Holders are entitled to vote or consent as one class, and none of the Holders of
Units or Additional Units shall have the right to vote or consent as a separate
class on any matter to which such Holders are entitled to vote or consent.

      The Parent Notes, the Subsidiary Notes and any Additional Units shall be
considered collectively as a single class for all purposes of this Indenture.
Holders of the Parent Notes, the Subsidiary Notes and Additional Parent Notes
and Additional Subsidiary Notes will vote and consent together on all matters to
which such Holders are entitled to vote or consent as one class, and none of the
Holders of the Parent Notes, the Subsidiary Notes or Additional Parent Notes and
Additional Subsidiary Notes shall have the right to vote or consent as a
separate class on any matter to which such Holders are entitled to vote or
consent.

      (B) The Parent Notes and the Subsidiary Notes comprising each Unit will
not be separable and will be transferable only as a Unit, so long as each of the
Parent Notes and the Subsidiary Notes are outstanding. The Units will initially
be issued in the form of a fully registered global security, which will be
deposited with The Depository Trust Company ("DTC"). The principal of, premium,
if any, and interest on the Notes (including Additional Amounts, if any, on the
Subsidiary Notes) will be payable at the office or agency of the Parent and the
Subsidiary Issuer maintained for such purpose in The City of New York, New York,
or


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at such other office or agency of the Parent and the Subsidiary Issuer as may be
maintained for such purpose pursuant to Section 1.3; provided, however, that, at
the option of the Parent or the Subsidiary Issuer, as the case may be, interest
may be paid by check mailed to addresses of the Persons entitled thereto as such
addresses shall appear on the Register. Payments in respect of the Parent Notes
and the Subsidiary Notes (including principal of, premium, if any, and interest
on the Notes (including Additional Amounts, if any, on the Subsidiary Notes))
will be made by wire transfer of immediately available funds to the accounts
specified by DTC.

      A form of the global Parent Note (the "Global Parent Note") is attached as
Exhibit A hereto, a form of the global Subsidiary Note (the "Global Subsidiary
Note") is attached as Exhibit B hereto, a form of the Parent Guarantee is
attached as Exhibit C hereto and a form of the global Unit (the "Global Unit")
is attached as Exhibit C hereto, each of which may include notations, legends or
endorsements required by law, stock exchange rule or usage, in addition to those
set forth on Exhibit A, Exhibit B, Exhibit C, Exhibit D and in Section 1.1(d).

      (C) The Notes and the Units shall be issuable only in registered form
without coupons and only as whole Units consisting of Notes in denominations,
subject to Section 802, of (i) $512 principal amount for the Parent Notes and
(ii) $488 principal amount for the Subsidiary Notes, or in each case, any
integral multiple of such whole Units.

      (D) The Global Unit (and all Units issued in exchange therefor or
substitution thereof) shall bear a legend substantially to the following effect
on the face thereof:

            "UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR UNITS IN
            DEFINITIVE FORM, THIS GLOBAL UNIT MAY NOT BE TRANSFERRED EXCEPT AS A
            WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY, OR BY THE
            DEPOSITARY OR NOMINEE OF SUCH DEPOSITARY, TO A SUCCESSOR DEPOSITARY
            OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY. TRANSFERS OF THIS GLOBAL
            UNIT SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN PART, TO
            NOMINEES OF CEDE & CO. OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR'S
            NOMINEE, AND TRANSFERS OR PORTIONS OF THIS GLOBAL UNIT SHALL BE
            LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET
            FORTH IN THE INDENTURE.

            UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE
            OF THE DEPOSITORY TRUST COMPANY ("DTC") TO THE PARENT AND THE
            SUBSIDIARY ISSUER OR THEIR AGENT FOR REGISTRATION OF TRANSFER,
            EXCHANGE OR PAYMENT, AND ANY CERTIFICATE IS REGISTERED IN THE NAME
            OF CEDE & CO. OR SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED
            REPRESENTATIVE OF DTC (AND ANY PAYMENT HEREON IS MADE TO CEDE & CO.
            OR SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE
            OF


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            DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR
            OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED
            OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN."

      (E) Book-Entry Provisions.

            (1)   This Section 1.1(e) shall apply only to the Global Unit
                  deposited with the Trustee, as custodian for DTC.

            (2)   The Global Unit initially shall (x) be registered in the name
                  of DTC for the Global Unit or the nominee of DTC, (y) be
                  delivered to the Trustee as custodian for DTC and (z) bear
                  legends as set forth in Section 1.1(d).

            (3)   Members of, or participants in, DTC ("Agent Members") shall
                  have no rights under this Indenture with respect to the Global
                  Unit held on their behalf by DTC or by the Trustee as the
                  custodian of DTC or under the Global Unit, and DTC may be
                  treated by the Parent, the Subsidiary Issuer or the Trustee
                  and any agent of the Parent, the Subsidiary Issuer or the
                  Trustee as the absolute owner of the Global Unit for all
                  purposes whatsoever. Notwithstanding the foregoing, nothing
                  herein shall prevent the Parent, the Subsidiary Issuer or the
                  Trustee or any agent of the Parent, the Subsidiary Issuer or
                  the Trustee from giving effect to any written certification,
                  proxy or other authorization furnished by DTC or impair, as
                  between DTC and its Agent Members, the operation of customary
                  practices of DTC governing the exercise of the rights of a
                  Holder of a beneficial interest in the Global Unit.

            (4)   In connection with any transfer of a portion of the beneficial
                  interest in the Global Unit pursuant to subsection (d) of this
                  Section to beneficial owners who are required to hold
                  Definitive Securities, the Registrar shall reflect on its
                  books and records the date and a decrease in the principal
                  amount of the Global Unit in an amount equal to the principal
                  amount of the beneficial interest in the Global Unit to be
                  transferred, and the Parent and the Subsidiary Issuer shall
                  execute, and the Trustee shall authenticate and deliver, one
                  or more Definitive Securities of like tenor and amount.

            (5)   In connection with the transfer of the Global Unit to
                  beneficial owners pursuant to subsection (d) of this Section,
                  the Global Unit shall be deemed to be surrendered to the
                  Trustee for cancellation, and the Parent and the Subsidiary
                  Issuer shall execute, and the Trustee shall authenticate and
                  deliver, to each beneficial owner identified by DTC in
                  exchange for its beneficial interest in the Global Unit, an
                  equal aggregate principal amount of Definitive Securities of
                  authorized denominations.


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            (6)   The registered Holder of the Global Unit may grant proxies and
                  otherwise authorize any person, including Agent Members and
                  persons that may hold interests through Agent Members, to take
                  any action which a Holder is entitled to take under this
                  Indenture or under the Notes or the Units.

      (F) Definitive Securities.

            (1)   Except as provided below, owners of beneficial interests in
                  the Global Unit will not be entitled to receive Definitive
                  Securities. If required to do so pursuant to any applicable
                  law or regulation, beneficial owners may obtain Definitive
                  Securities in exchange for their beneficial interests in the
                  Global Unit upon written request in accordance with DTC's and
                  the Registrar's procedures. In addition, Definitive Securities
                  shall be transferred to all beneficial owners in exchange for
                  their beneficial interests in the Global Unit if (a) the
                  Parent and the Subsidiary Issuer notify the Trustee in writing
                  that DTC is unwilling or unable to continue as Depositary for
                  the Global Unit or DTC ceases to be a clearing agency
                  registered under the Exchange Act, at a time when DTC is
                  required to be so registered in order to act as Depositary,
                  and in each case a successor Depositary is not appointed by
                  the Parent and the Subsidiary Issuer within 90 days of such
                  notice or cessation, (b) each of the Parent and the Subsidiary
                  Issuer executes and delivers to the Trustee and the Registrar
                  an Officers' Certificate stating that the Global Unit shall be
                  so exchangeable or (c) an Event of Default has occurred and is
                  continuing and the Registrar has received a request from DTC
                  that the Global Unit be so exchanged. Upon the occurrence of
                  any of the preceding events in (a), (b) or (c) above,
                  Definitive Securities shall be issued in such names as DTC
                  shall instruct the Trustee.

            (2)   Any Definitive Securities delivered in exchange for interest
                  in the Global Unit pursuant to Section 1.1(e)(4) or (5) shall
                  bear the applicable legend, as set forth in Section 1.1(d).

            (3)   In connection with the exchange of a portion of a Definitive
                  Security for a beneficial interest in the Global Unit, the
                  Trustee shall cancel such Definitive Security, and the Parent
                  and the Subsidiary Issuer shall execute, and the Trustee shall
                  authenticate and deliver, to the transferring Holder a new
                  Definitive Security representing the principal amount not so
                  transferred.

      SECTION 1.2. EXECUTION AND AUTHENTICATION

      The Parent Notes shall be signed by one Officer of the Parent by either
manual or facsimile signature. The Subsidiary Notes shall be signed by one
Officer of the Subsidiary Issuer by either manual or facsimile signature. The
Units shall be signed by one Officer of the Parent and one Officer of the
Subsidiary Issuer by either manual or facsimile signature. If an Officer whose
signature is on a Note or a Unit no longer holds that office at the time the
Trustee


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authenticates the Note or the Unit, as the case may be, such Note or Unit shall
be valid nevertheless.

      A Note or Unit shall not be valid until an authorized signatory of the
Trustee manually authenticates the Note or Unit, as the case may be. The
signature of the Trustee on a Note or Unit shall be conclusive evidence that
such Note or Unit has been duly and validly authenticated and issued under this
Indenture. A Note or Unit shall be dated the date of its authentication.

      The Trustee may appoint an agent (the "Authenticating Agent") reasonably
acceptable to the Parent and the Subsidiary Issuer to authenticate the Notes and
the Units. Unless limited by the terms of such appointment, any such
Authenticating Agent may authenticate the Notes and the Units whenever the
Trustee may do so. Each reference in this Indenture to authentication by the
Trustee includes authentication by the Authenticating Agent. An Authenticating
Agent has the same rights as a Paying Agent to deal with Holders or an Affiliate
of the Parent and the Subsidiary Issuer.

      SECTION 1.3. REGISTRAR AND PAYING AGENT

      The Parent and the Subsidiary Issuer shall maintain an office or agency
where Notes and Units may be presented for registration of transfer or for
exchange (the "Registrar") and an office or agency where Notes may be presented
for payment (the "Paying Agent"). The Parent and the Subsidiary Issuer shall
cause each of the Registrar and the Paying Agent to maintain an office or agency
in New York, New York. The Registrar shall keep a register of the Notes and
Units and of their transfer and exchange (the "Register"). The Parent and the
Subsidiary Issuer may have one or more co-registrars and one or more additional
paying agents. The term "Paying Agent" includes any additional paying agent.

      The Parent and the Subsidiary Issuer shall enter into an appropriate
agency agreement with any Registrar, Paying Agent or co-registrar not a party to
this Indenture, which shall incorporate the terms of the TIA. The agreement
shall implement the provisions of this Indenture that relate to such agent. The
Parent and the Subsidiary Issuer shall notify the Trustee of the name and
address of each such agent. If the Parent and the Subsidiary Issuer fail to
maintain a Registrar or Paying Agent, the Trustee shall act as such and shall be
entitled to appropriate compensation therefor pursuant to Section 607. The
Parent or the Subsidiary Issuer may act as Paying Agent, Registrar, co-registrar
or transfer agent.

      The Parent and the Subsidiary Issuer initially appoints the Trustee as
Registrar and Paying Agent.

      SECTION 1.4. PAYING AGENT TO HOLD MONEY IN TRUST

      By no later than 10:00 a.m. (New York City time) on the date on which any
principal of or interest on any Note is due and payable, the Parent and the
Subsidiary Issuer shall deposit with the Paying Agent a sum sufficient in
immediately available funds to pay such principal or interest when due. The
Parent and the Subsidiary Issuer shall require each Paying Agent (other than the
Trustee) to agree in writing that such Paying Agent shall hold in trust for the
benefit of the Holders or the Trustee all money held by such Paying Agent for
the payment of principal of or interest on the Notes and shall notify the
Trustee in writing of any default by any of the Parent


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or the Subsidiary Issuer in making any such payment. If either the Parent or the
Subsidiary Issuer acts as Paying Agent, it shall segregate the money held by it
as Paying Agent and hold it as a separate trust fund. The Parent or the
Subsidiary Issuer at any time may require a Paying Agent (other than the
Trustee) to pay all money held by it to the Trustee and to account for any funds
disbursed by such Paying Agent. Upon complying with this Section, the Paying
Agent (if other than the Parent or the Subsidiary Issuer, as the case may be)
shall have no further liability for the money delivered to the Trustee. Upon any
bankruptcy, reorganization or similar proceeding with respect to the Parent or
the Subsidiary Issuer, the Trustee shall serve as Paying Agent for the Notes.

      SECTION 1.5. HOLDER LISTS

      The Trustee shall preserve in as current a form as is reasonably
practicable the most recent list available to it of the names and addresses of
Holders of Notes and Units. If the Trustee is not the Registrar, or to the
extent otherwise required under the TIA, the Parent and the Subsidiary Issuer
shall furnish to the Trustee, in writing at least five Business Days before each
Interest Payment Date and at such other times as the Trustee may request in
writing, a list in such form and as of such date as the Trustee may reasonably
require of the names and addresses of Holders.

      SECTION 1.6. MUTILATED, DESTROYED, LOST OR STOLEN NOTES AND UNITS

      If a mutilated Note or Unit is surrendered to the Registrar or if the
Holder of a Note or Unit claims that such Note or Unit has been lost, destroyed
or wrongfully taken, the Parent and/or the Subsidiary Issuer, as the case may
be, shall issue and the Trustee shall authenticate a replacement Note or Unit if
the requirements of Section 8-405 of the Uniform Commercial Code are met and the
Holder satisfies any other reasonable requirements of the Trustee. If required
by the Trustee, the Parent and/or the Subsidiary Issuer, as the case may be,
such Holder shall furnish an indemnity sufficient in the judgment of the
Trustee, the Parent and/or the Subsidiary Issuer, as the case may be, to protect
the Parent and/or the Subsidiary Issuer, the Trustee, the Paying Agent, the
Registrar and any co-registrar from any loss which any of them may suffer if a
Note or Unit is replaced, and, in the absence of notice to the Parent and/or the
Subsidiary Issuer, as the case may be, and the Trustee that such Note or Unit
has been acquired by a bona fide purchaser, the Parent and/or the Subsidiary
Issuer, as the case may be, shall execute by either manual or facsimile
signature (and the Trustee shall authenticate and make available for delivery),
in exchange for any such mutilated Note or Unit or in lieu of any such
destroyed, lost or stolen Note or Unit, a new Note or Unit of like tenor and
principal amount, bearing a number not contemporaneously outstanding.

      In case any such mutilated, destroyed, lost or stolen Note or Unit has
become or is about to become due and payable, the Parent and/or the Subsidiary
Issuer, as the case may be, in its discretion may, instead of issuing a new Note
or Unit, pay such Note or Unit.

      Upon the issuance of any new Note or Unit under this Section, the Parent
and/or the Subsidiary Issuer, as the case may be, may require the payment by the
Holder thereof of a sum sufficient to cover any tax or other governmental charge
that may be imposed in relation thereto and any other expenses (including the
fees and expenses of the Trustee) in connection therewith.


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      Every new Note or Unit issued pursuant to this Section in lieu of any
mutilated, destroyed, lost or stolen Note or Unit shall constitute an original
additional contractual obligation of the Parent and/or the Subsidiary Issuer, as
the case may be, and any other obligor upon the Note or Unit, whether or not the
mutilated, destroyed, lost or stolen Note or Unit shall be at any time
enforceable by anyone, and shall be entitled to all benefits of this Indenture
equally and proportionately with any and all other Notes and Units duly issued
hereunder.

      The provisions of this Section are exclusive and shall preclude (to the
extent lawful) all other rights and remedies with respect to the replacement or
payment of mutilated, destroyed, lost or stolen Notes or Units.

      SECTION 1.7. OUTSTANDING NOTES AND UNITS

      Notes and Units outstanding at any time are all Notes and Units
authenticated by the Trustee except for those canceled by it, those delivered to
it for cancellation and those described in this Section 1.7 as not outstanding.
A Note or Unit, as the case may be, ceases to be outstanding in the event the
Parent or the Subsidiary Issuer or a subsidiary of the Parent or the Subsidiary
Issuer holds such Note or Unit, provided, however, that (i) for purposes of
determining which are outstanding for consent or voting purposes hereunder,
Notes and Units shall cease to be outstanding in the event the Parent or the
Subsidiary Issuer or an Affiliate of the Parent or the Subsidiary Issuer holds
such Note or Unit and (ii) in determining whether the Trustee shall be protected
in making a determination whether the Holders of the requisite principal amount
of outstanding Notes or Units are present at a meeting of Holders of Notes or
Units for quorum purposes or have consented to or voted in favor of any request,
demand, authorization, direction, notice, consent, waiver, amendment or
modification hereunder, or relying upon any such quorum, consent or vote, only
Notes or Units which a Trust Officer of the Trustee actually knows to be held by
the Parent or the Subsidiary Issuer or an Affiliate of the Parent or the
Subsidiary Issuer shall not be considered outstanding.

      If a Note or Unit is replaced pursuant to Section 1.6, it ceases to be
outstanding unless the Trustee, the Parent and the Subsidiary Issuer receive
proof satisfactory to them that the replaced Note or Unit, as the case may be,
is held by a bona fide purchaser.

      If the Paying Agent segregates and holds in trust, in accordance with this
Indenture, on a Redemption Date or Stated Maturity money sufficient to pay all
principal and interest payable on that date with respect to the Notes or Units
(or portions thereof) to be redeemed or maturing, as the case may be, and the
Paying Agent is not prohibited from paying such money to the Holders on that
date pursuant to the terms of this Indenture, then on and after that date such
Notes or Units (or portions thereof) cease to be outstanding and interest on
them ceases to accrue.

      SECTION 1.8. TEMPORARY NOTES AND UNITS

      Until Definitive Securities are ready for delivery, the Parent and the
Subsidiary Issuer may prepare and the Trustee shall authenticate temporary
Parent Notes, temporary Subsidiary Notes and temporary Units (together, the
"Temporary Securities"). Temporary Securities shall be substantially in the form
of the Definitive Securities but may have variations that the Parent and the
Subsidiary Issuer consider appropriate for Temporary Securities. Without
unreasonable


                                       9
<PAGE>
delay, the Parent and the Subsidiary Issuer shall prepare and the Trustee shall
authenticate Definitive Securities. After the preparation of Definitive
Securities, the Temporary Securities shall be exchangeable for Definitive
Securities upon surrender of the Temporary Securities at any office or agency
maintained by the Parent and the Subsidiary Issuer for that purpose and such
exchange shall be without charge to the Holder. Upon surrender for cancellation
of any one or more Temporary Securities, the Parent and the Subsidiary Issuer
shall execute, and the Trustee shall authenticate and make available for
delivery in exchange therefor, one or more Definitive Securities representing an
equal principal amount of Parent Notes, Subsidiary Notes and Units. Until so
exchanged, the Holder of Temporary Securities shall in all respects be entitled
to the same benefits under this Indenture as a Holder of Definitive Securities.

      SECTION 1.9. CANCELLATION

      The Parent and the Subsidiary Issuer at any time may deliver Notes or
Units to the Trustee for cancellation. The Registrar and the Paying Agent shall
forward to the Trustee any Notes or Units surrendered to them for registration
of transfer, exchange or payment. The Trustee and no one else shall cancel and
return to the Parent and/or the Subsidiary Issuer, as the case may be, all Note
and Units surrendered for registration of transfer, exchange, payment or
cancellation. The Parent and the Subsidiary Issuer may not issue new Notes or
Units to replace Notes or Units it has paid or delivered to the Trustee for
cancellation for any reason other than in connection with a transfer or
exchange.

      SECTION 1.10. PAYMENT OF INTEREST; DEFAULTED INTEREST

      Interest on the Notes which is payable, and is punctually paid or duly
provided for, on any interest payment date shall be paid to the Person in whose
name the Notes are registered at the close of business on the regular record
date for such interest at the office or agency of the Parent or the Subsidiary
Issuer, as the case may be, maintained for such purpose pursuant to Section 1.3.

      Any interest on any Parent Note or Subsidiary Note, which is payable, but
is not paid when the same becomes due and payable and such nonpayment continues
for a period of 30 days shall forthwith cease to be payable to the Holder on the
regular record date by virtue of having been such Holder, and such defaulted
interest and (to the extent lawful) interest on such defaulted interest at the
rate borne by the Notes (such defaulted interest and interest thereon herein
collectively called "Defaulted Interest") shall be paid by the Parent or the
Subsidiary Issuer, as the case may be, at its election in each case, as provided
in clause (a) or (b) below:

      (A) The Parent or the Subsidiary Issuer, as the case may be, may elect to
make payment of any Defaulted Interest to the Persons in whose names the Note is
registered at the close of business on a Special Record Date (as defined below)
for the payment of such Defaulted Interest, which shall be fixed in the
following manner. The Parent or the Subsidiary Issuer, as the case may be, shall
notify the Trustee in writing of the amount of Defaulted Interest proposed to be
paid on each Note and the date (not less than 30 days after such notice) of the
proposed payment (the "Special Interest Payment Date"), and at the same time the
Parent or the Subsidiary Issuer, as the case may be, shall deposit with the
Trustee an amount of money equal to the aggregate amount proposed to be paid in
respect of such Defaulted Interest or shall make arrangements


                                       10
<PAGE>
satisfactory to the Trustee for such deposit prior to the date of the proposed
payment, such money when deposited to be held in trust for the benefit of the
Persons entitled to such Defaulted Interest as in this clause provided.
Thereupon the Trustee shall fix a record date (the "Special Record Date") for
the payment of such Defaulted Interest which shall be not more than 15 days and
not less than 10 days prior to the Special Interest Payment Date and not less
than 10 days after the receipt by the Trustee of the notice of the proposed
payment. The Trustee shall promptly notify the Parent or the Subsidiary Issuer,
as the case may be, of such Special Record Date, and in the name and at the
expense of the Parent or the Subsidiary Issuer, as the case may be, shall cause
notice of the proposed payment of such Defaulted Interest and the Special Record
Date and Special Interest Payment Date therefor to be given in the manner
provided for in Section 12.2, not less than 10 days prior to such Special Record
Date. Notice of the proposed payment of such Defaulted Interest and the Special
Record Date and Special Interest Payment Date therefor having been so given,
such Defaulted Interest shall be paid on the Special Interest Payment Date to
the Persons in whose names the Units are registered at the close of business on
such Special Record Date and shall no longer be payable pursuant to the
following clause (b).

      (B) The Parent or the Subsidiary Issuer, as the case may be, may make
payment of any Defaulted Interest in any other lawful manner not inconsistent
with the requirements of any securities exchange on which the Units may be
listed, and upon such notice as may be required by such exchange, if, after
notice given by the Parent or the Subsidiary Issuer, as the case may be, to the
Trustee of the proposed payment pursuant to this clause, such manner of payment
shall be deemed practicable by the Trustee.

      Subject to the foregoing provisions of this Section, each Note delivered
under this Indenture upon registration of, transfer of or in exchange for or in
lieu of any other Note shall carry the rights to interest accrued and unpaid,
and to accrue, which were carried by such other Note.

      SECTION 1.11. COMPUTATION OF INTEREST

      Interest on the Notes shall be computed on the basis of a 360-day year of
twelve 30-day months. Solely for purposes of the Interest Act (Canada), the
yearly rate of interest to which interest calculated for a period of less than
one year on the basis of a year of 360 days consisting of 12 30-day periods is
equivalent is such rate of interest multiplied by a fraction of which (i) the
numerator is the product of (A) the actual number of days in the year commencing
on the first day of such period, multiplied by (B) the sum of (y) the product of
30 multiplied by the number of complete months elapsed in such period and (z)
the actual number of days elapsed in any incomplete month in such period; and
(ii) the denominator is the product of (a) 360 multiplied by (b) the actual
number of days in such period. The Trustee shall have no obligation to calculate
interest under the Interest Act (Canada).

      SECTION 1.12. CUSIP AND ISIN NUMBERS

      The Parent and the Subsidiary Issuer in issuing the Notes and Units may
use "CUSIP" and "ISIN" numbers (if then generally in use) and, if so, the
Trustee shall use "CUSIP" and "ISIN" numbers in notices of redemption as a
convenience to Holders; provided, however, that any such notice may state that
no representation is made as to the correctness of such numbers either as
printed on the Units or as contained in any notice of a redemption and that
reliance may be placed only on the other identification numbers printed on the
Notes and Units, and any such redemption shall not be affected by any defect in
or omission of such CUSIP or ISIN numbers.


                                       11
<PAGE>
The Parent and the Subsidiary Issuer shall promptly notify the Trustee of any
change in the CUSIP and ISIN numbers.

      SECTION 1.13. REDEMPTION AND REPURCHASE

      (A) There shall be no sinking fund for the retirement of the Parent Notes
or the Subsidiary Notes or other mandatory redemption obligation.

      (B) The Parent and Subsidiary Issuer, at their joint option, may redeem
the Units in accordance with the provisions of the Parent Notes, the Subsidiary
Notes and the Indenture, including, without limitation, Article Eleven.

      (C) The Parent and Subsidiary Issuer, at the option of the Holders
thereof, shall jointly repurchase the Units in accordance with the provisions of
the Parent Notes, the Subsidiary Notes and the Indenture, including, without
limitation, Sections 1009 and 1017.

      SECTION 1.14. CONVERSION

      The Units, the Parent Notes and the Subsidiary Notes shall not be
convertible into any other securities.

      SECTION 1.15. MATURITY

      The Stated Maturity of the Parent Notes and the Subsidiary Notes shall be
September 15, 2013.

      SECTION 1.16. PARENT SECURITIES

      The Subsidiary Notes shall be guaranteed by the Parent in accordance with
the provisions of Article Thirteen and Exhibit C hereto.

      SECTION 1.17. OTHER TERMS OF PARENT NOTES, SUBSIDIARY NOTES AND UNITS

      Without limiting the foregoing provisions of this Article I, the terms of
the Parent Notes, the Subsidiary Notes and the Units shall be as provided in the
forms of the Parent Notes, the Subsidiary Notes and the Units as set forth in
Exhibit A, Exhibit B, and Exhibit C respectively, hereto and as provided in the
Indenture.

                                   ARTICLE II

                      AMENDMENTS TO THE ORIGINAL INDENTURES

      SECTION 2.1. AMENDMENTS APPLICABLE ONLY TO THE PARENT NOTES, THE
SUBSIDIARY NOTES AND THE UNITS

      The amendments and supplements contained herein shall apply to the Parent
Note, the Subsidiary Notes and the Units only and not to any other series of
Securities issued under the Original Indentures, and any covenants provided
herein are expressly being included solely for the benefit


                                       12
<PAGE>
of the Parent Note, the Subsidiary and the Units. These amendments and
supplements shall be effective for so long as there remain any Parent Notes,
Subsidiary Notes or Units outstanding.

      SECTION 2.2. DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

      (A) Section 101 of each of the Original Indentures is amended and
supplemented by inserting or restating, as the case may be, in their appropriate
alphabetical position, the following definitions:

      "ACNTA" means (without duplication), as of the date of determination:

      (a)   the sum of:

            (1)   discounted future net revenue from proved crude oil and
                  natural gas reserves of the Parent and its Restricted
                  Subsidiaries calculated in accordance with SEC guidelines
                  before any state or federal income taxes, as estimated in a
                  reserve report prepared as of the end of the Parent's most
                  recently completed fiscal year, which reserve report is
                  prepared or reviewed by independent petroleum engineers, as
                  increased by, as of the date of determination, the discounted
                  future net revenue of

                  (A)   estimated proved crude oil and natural gas reserves of
                        the Parent and its Restricted Subsidiaries attributable
                        to acquisitions consummated since the date of such
                        year-end reserve report, and

                  (B)   estimated crude oil and natural gas reserves of the
                        Parent and its Restricted Subsidiaries attributable to
                        extensions, discoveries and other additions and upward
                        determinations of estimates of proved crude oil and
                        natural gas reserves (including previously estimated
                        development costs incurred during the period and the
                        accretion of discount since the prior year end) due to
                        exploration, development or exploitation, production or
                        other activities which reserves were not reflected in
                        such year-end reserve report,

                  in each case calculated in accordance with SEC guidelines
                  (utilizing the prices utilized in such year-end reserve
                  report), and decreased by, as of the date of determination,
                  the discounted future net revenue attributable to

                  (C)   estimated proved crude oil and natural gas reserves of
                        the Parent and its Restricted Subsidiaries reflected in
                        such year-end reserve report produced or disposed of
                        since the date of such year-end reserve report and

                  (D)   reductions in the estimated oil and gas reserves of the
                        Parent and its Restricted Subsidiaries reflected in such
                        year-end reserve report since the date of such year-end
                        reserve report attributable to downward determinations
                        of estimates of proved crude oil and natural gas
                        reserves due to exploration, development or


                                       13
<PAGE>
                        exploitation, production or other activities conducted
                        or otherwise occurring since the date of such year-end
                        reserve report,

                  in each case calculated in accordance with SEC guidelines
                  (utilizing the prices utilized in such year-end reserve
                  report); provided, however, that, in the case of each of the
                  determinations made pursuant to clauses (A) through (D), such
                  increases and decreases shall be as estimated by the Parent's
                  engineers;

            (2)   the capitalized costs that are attributable to crude oil and
                  natural gas properties of the Parent and its Restricted
                  Subsidiaries to which no proved crude oil and natural gas
                  reserves are attributed, based on the Parent's books and
                  records as of a date no earlier than the date of the Parent's
                  latest annual or quarterly financial statements;

            (3)   the Net Working Capital on a date no earlier than the date of
                  the Parent's latest annual or quarterly financial statements;
                  and

            (4)   the greater of (I) the net book value on a date no earlier
                  than the date of the Parent's latest annual or quarterly
                  financial statements and (II) the appraised value, as
                  estimated by independent appraisers, of other tangible assets
                  of the Parent and its Restricted Subsidiaries as of a date no
                  earlier than the date of the Parent's latest audited financial
                  statements (provided that the Parent shall not be required to
                  obtain such an appraisal of such assets if no such appraisal
                  has been performed); minus

      (b) to the extent not otherwise taken into account in the immediately
preceding clause (a), the sum of:

            (1)   minority interests;

            (2)   any net gas balancing liabilities of the Parent and its
                  Restricted Subsidiaries reflected in the Parent's latest
                  audited financial statements;

            (3)   the discounted future net revenue, calculated in accordance
                  with SEC guidelines (utilizing the same prices utilized in the
                  Parent's year-end reserve report), attributable to reserves
                  subject to participation interests, overriding royalty
                  interests or other interests of third parties, pursuant to
                  participation, partnership, vendor financing or other
                  agreements then in effect, or which otherwise are required to
                  be delivered to third parties;

            (4)   the discounted future net revenue, calculated in accordance
                  with SEC guidelines (utilizing the same prices utilized in the
                  Parent's year-end reserve report), attributable to reserves
                  that are required to be delivered to third parties to fully
                  satisfy the obligations of the Parent and its Restricted
                  Subsidiaries with respect to volumetric Production Payments on
                  the schedules specified with respect thereto; and


                                       14
<PAGE>
            (5)   the discounted future net revenue, calculated in accordance
                  with SEC guidelines, attributable to reserves subject to
                  dollar-denominated Production Payments that, based on the
                  estimates of production included in determining the discounted
                  future net revenue specified in the immediately preceding
                  clause (a)(1) (utilizing the same prices utilized in the
                  Parent's year-end reserve report), would be necessary to
                  satisfy fully the obligations of the Parent and its Restricted
                  Subsidiaries with respect to dollar-denominated Production
                  Payments on the schedules specified with respect thereto.

      "Acquired Indebtedness" means Indebtedness (i) of a Person or any of its
Subsidiaries existing at the time such Person becomes a Restricted Subsidiary or
(ii) assumed in connection with the acquisition of assets from such Person, in
each case whether or not Incurred by such Person in connection with, or in
anticipation or contemplation of, such Person becoming a Restricted Subsidiary
of the Parent or such acquisition. Acquired Indebtedness shall be deemed to have
been incurred, with respect to clause (i) of the preceding sentence, on the date
such Person becomes a Restricted Subsidiary and, with respect to clause (ii) of
the preceding sentence, on the date of consummation of such acquisition of
assets.

      "Additional Assets" means:

            (1)   any property or assets (other than Indebtedness and Capital
                  Stock) to be used by the Parent or a Restricted Subsidiary in
                  the Oil and Gas Business;

            (2)   the Capital Stock of a Person that becomes a Restricted
                  Subsidiary as a result of the acquisition of such Capital
                  Stock by the Parent or a Restricted Subsidiary of the Parent;

            (3)   Capital Stock constituting a minority interest in any Person
                  that at such time is a Restricted Subsidiary of the Parent; or

            (4)   the development or exploitation of Oil and Gas Properties;

provided, however, that, in the case of clauses (2) and (3), such Restricted
Subsidiary is primarily engaged in the Oil and Gas Business.

      "Additional Notes" means Parent Notes or Subsidiary Notes, as the case may
be, that are issued under a supplemental indenture after the date that the
Notes, as Units, are first issued by the Parent or the Subsidiary Issuer, as the
case may be, and authenticated by the Trustee under this Indenture, which will
rank pari passu with the Parent Notes or Subsidiary Notes, as the case may be,
initially issued in all respects, except that interest will only accrue on such
Additional Notes as and from the issue date of such Additional Notes or such
other date as set forth in the terms of such Additional Notes.

      "Additional Units" means Units that are issued under a supplemental
indenture after the date that the Units are first issued by the Parent and the
Subsidiary Issuer and authenticated by the Trustee under this Indenture, which
will consist of Additional Notes.


                                       15
<PAGE>
      "Affiliate" of any specified Person means any other Person, directly or
indirectly, controlling or controlled by or under direct or indirect common
control with such specified Person. For the purposes of this definition,
"control" when used with respect to any Person means the power to direct the
management and policies of such Person, directly or indirectly, whether through
the ownership of voting securities, by contract or otherwise; and the terms
"controlling" and "controlled" have meanings correlative to the foregoing;
provided that beneficial ownership of 10% or more of the Voting Stock of a
Person shall be deemed to be control.

      "Asset Disposition" means any direct or indirect sale, lease (other than
an operating lease entered into in the ordinary course of business), transfer,
issuance or other disposition, or a series of related sales, leases, transfers,
issuances or dispositions that are part of a common plan, of shares of Capital
Stock of a Subsidiary (other than directors' qualifying shares), property or
other assets (each referred to for the purposes of this definition as a
"disposition") by the Parent or any of its Restricted Subsidiaries, including
any disposition by means of a merger, consolidation or similar transaction.

      Notwithstanding the preceding, the following items shall not be deemed to
be Asset Dispositions:

      (1)   a disposition by a Restricted Subsidiary to the Parent or by the
            Parent or a Restricted Subsidiary to a Restricted Subsidiary;

      (2)   the sale of Cash Equivalents in the ordinary course of business;

      (3)   a disposition of obsolete or worn out equipment or equipment that is
            no longer useful in the conduct of the business of the Parent and
            its Restricted Subsidiaries and that is disposed of in each case in
            the ordinary course of business;

      (4)   transactions permitted under Section 801;

      (5)   an issuance of Capital Stock by a Restricted Subsidiary of the
            Parent to the Parent or to a Wholly-Owned Subsidiary;

      (6)   for purposes of Section 1009 only, the making of a Permitted
            Investment or a disposition subject to Section 1005;

      (7)   an Asset Swap effected in compliance with Section 1011; other than
            Section 1011(a)(2);

      (8)   dispositions of assets in a single transaction or series of related
            transactions with an aggregate fair market value in any calendar
            year of less than $2 million;

      (9)   dispositions in connection with Permitted Liens;

      (10)  dispositions of receivables in connection with the compromise,
            settlement or collection thereof in the ordinary course of business
            or in bankruptcy or similar proceedings and exclusive of factoring
            or similar arrangements;


                                       16
<PAGE>
      (11)  the abandonment, assignment, lease, sublease or farm-out of Oil and
            Gas Properties, or the forfeiture or other disposition of such
            properties pursuant to standard form operating agreements, in each
            case in the ordinary course of business in a manner that is
            customary in a Related Business;

      (12)  any disposition of inventory, hydrocarbons or other mineral products
            in the ordinary course of business;

      (13)  the licensing or sublicensing of intellectual property or other
            general intangibles and licenses, leases or subleases of other
            property; and

      (14)  foreclosure on assets.

      "Asset Swap" means concurrent purchase and sale or exchange of Related
Business Assets between the Parent or any of its Restricted Subsidiaries and
another Person; provided that any cash received must be applied in accordance
with Section 1009.

      "Attributable Indebtedness" in respect of a Sale/Leaseback Transaction
means, as at the time of determination, the present value (discounted at the
interest rate borne by the Notes, compounded semi-annually) of the total
obligations of the lessee for rental payments during the remaining term of the
lease included in such Sale/Leaseback Transaction (including any period for
which such lease has been extended).

      "Average Life" means, as of the date of determination, with respect to any
Indebtedness or Preferred Stock, the quotient obtained by dividing (1) the sum
of the products of the numbers of years from the date of determination to the
dates of each successive scheduled principal payment of such Indebtedness or
redemption or similar payment with respect to such Preferred Stock multiplied by
the amount of such payment by (2) the sum of all such payments.

      "Bank Indebtedness" means any and all amounts, whether outstanding on the
Issue Date or Incurred after the Issue Date, payable by the Parent or the
Subsidiary Issuer under or in respect of the Existing Credit Facilities, and any
related notes, collateral documents, letters of credit and guarantees and any
Interest Rate Agreement entered into in connection with the such credit
agreements, including principal, premium, if any, interest (including interest
accruing on or after the filing of any petition in bankruptcy or for
reorganization relating to the Parent at the rate specified therein whether or
not a claim for post filing interest is allowed in such proceedings), fees,
charges, expenses, reimbursement obligations, guarantees and all other amounts
payable thereunder or in respect thereof.

      "Bankruptcy Law" means Title 11, United States Code, or any similar U.S.
federal or state law for the relief of debtors.

      "Board of Directors" means, with respect to any Person, the board of
directors of such Person or any duly authorized committee thereof.

      "Board Resolution" means a copy of a resolution certified by the Secretary
or an Assistant Secretary of the Parent or the Subsidiary Issuer, as applicable,
to have been duly


                                       17
<PAGE>
adopted by such Board of Directors and to be in full force and effect on the
date of such certification, and delivered to the Trustee.

      "Business Day" means each day that is not a Saturday, Sunday or other day
on which banking institutions in New York, New York are authorized or required
by law to close.

      "Capital Stock" of any Person means any and all shares, interests, rights
to purchase, warrants, options, participation or other equivalents of or
interests in (however designated) equity of such Person, including any Preferred
Stock, but excluding any debt securities convertible into such equity.

      "Capitalized Lease Obligations" means an obligation that is required to be
classified and accounted for as a capitalized lease for financial reporting
purposes in accordance with GAAP, and the amount of Indebtedness represented by
such obligation will be the capitalized amount of such obligation at the time
any determination thereof is to be made as determined in accordance with GAAP,
and the Stated Maturity thereof will be the date of the last payment of rent or
any other amount due under such lease prior to the first date such lease may be
terminated without penalty.

      "Cash Equivalents" means:

      (1)   securities issued or directly and fully guaranteed or insured by the
            United States Government or the Canadian Government or any agency or
            instrumentality of the United States or Canada (provided that the
            full faith and credit of the United States or Canada is pledged in
            support thereof), having maturities of not more than one year from
            the date of acquisition;

      (2)   marketable general obligations issued by any state of the United
            States of America or province of Canada or any political subdivision
            of any such state or province or any public instrumentality thereof
            maturing within one year from the date of acquisition of the United
            States or Canada (provided that the full faith and credit of the
            United States or Canada, respectively, is pledged in support
            thereof) and, at the time of acquisition, having a credit rating of
            "A" or better from either S&P or Moody's or, in the case of a
            Canadian issuer, Dominion Rating Service Limited or Canadian Bond
            Service Limited;

      (3)   certificates of deposit, time deposits, eurodollar time deposits,
            overnight bank deposits or bankers' acceptances having maturities of
            not more than one year from the date of acquisition thereof issued
            by any commercial bank the long-term debt of which is rated at the
            time of acquisition thereof at least "A" or the equivalent thereof
            by S&P, "A" or the equivalent thereof by Moody's, "B" of the
            equivalent thereof by Thompson Bank Watch Rating or, in the case of
            a Canadian issuer, "A" or the equivalent thereof by Dominion Rating
            Service Limited or Canadian Bond Service Limited, and having
            combined capital and surplus in excess of $500 million;


                                       18
<PAGE>
      (4)   repurchase obligations with a term of not more than seven days for
            underlying securities of the types described in clauses (1), (2) and
            (3) entered into with any bank meeting the qualifications specified
            in clause (3) above;

      (5)   commercial paper rated at the time of acquisition thereof at least
            "A-1" or the equivalent thereof by S&P, "P-1" or the equivalent
            thereof by Moody's or, in the case of a Canadian issuer, "R-1" or
            the equivalent thereof by Dominion Rating Service Limited or
            Canadian Bond Service Limited, or carrying an equivalent rating by a
            nationally recognized rating agency, if both of the two named rating
            agencies cease publishing ratings of investments, and in any case
            maturing within one year after the date of acquisition thereof; and

      (6)   interests in any investment company or money market fund which
            invests 95% or more of its assets in instruments of the type
            specified in clauses (1) through (5) above.

      "Change of Control" means:

      (1)   any "person" or "group" of related persons (as such terms are used
            in Sections 13(d) and 14(d) of the Exchange Act) is or becomes the
            beneficial owner (as defined in Rules 13d-3 and 13d-5 under the
            Exchange Act, except that such person or group shall be deemed to
            have "beneficial ownership" of all shares that any such person or
            group has the right to acquire, whether such right is exercisable
            immediately or only after the passage of time), directly or
            indirectly, of more than 50% of the total voting power of the Voting
            Stock of the Parent (or its successor by merger, consolidation or
            purchase of all or substantially all of its assets) (for the
            purposes of this clause, such person or group shall be deemed to
            beneficially own any Voting Stock of the Parent held by a parent
            entity, if such person or group "beneficially owns" (as defined
            above), directly or indirectly, more than 50% of the voting power of
            the Voting Stock of such entity); or

      (2)   during any period of two consecutive years, individuals who at the
            beginning of such period constituted the Board of Directors of the
            Parent (together with any new directors whose election by such Board
            of Directors or whose nomination for election by the stockholders of
            the Parent was approved by a vote of 66-2/3% of the directors of the
            Parent then still in office who were either directors at the
            beginning of such period or whose election or nomination for
            election was previously so approved) cease for any reason to
            constitute a majority of the Board of Directors then in office; or

      (3)   the sale, lease, transfer, conveyance or other disposition (other
            than by way of merger or consolidation), in one or a series of
            related transactions, of all or substantially all of the assets of
            the Parent and its Restricted Subsidiaries taken as a whole to any
            "person" (as such term is used in Sections 13(d) and 14(d) of the
            Exchange Act); or


                                       19
<PAGE>
      (4)   the adoption by the stockholders of the Parent of a plan or proposal
            for the liquidation or dissolution of the Parent.

      "Code" means the U.S. Internal Revenue Code of 1986, as amended.

      "Commodity Agreements" means, with respect to any Person, any forward
contract, commodity swap agreement, commodity option agreement or other similar
agreement or arrangement designed to protect such Person against fluctuation in
commodity prices.

      "Common Stock" means with respect to any Person, any and all shares,
interests or other participations in, and other equivalents (however designated
and whether voting or nonvoting) of such Person's common stock whether or not
outstanding on the Issue Date, and includes, without limitation, all series and
classes of such common stock.

      "Consolidated Coverage Ratio" means as of any date of determination, with
respect to any Person, the ratio of (x) the aggregate amount of Consolidated
EBITDA of such Person for the period of the most recent four consecutive fiscal
quarters ending prior to the date of such determination for which financial
statements are in existence to (y) Consolidated Interest Expense for such four
fiscal quarters, provided, however, that:

      (1)   if the Parent or any Restricted Subsidiary:

            (a)   has Incurred any Indebtedness since the beginning of such
                  period that remains outstanding on such date of determination
                  or if the transaction giving rise to the need to calculate the
                  Consolidated Coverage Ratio is an Incurrence of Indebtedness,
                  Consolidated EBITDA and Consolidated Interest Expense for such
                  period will be calculated after giving effect on a pro forma
                  basis to such Indebtedness as if such Indebtedness had been
                  Incurred on the first day of such period (except that in
                  making such computation, the amount of Indebtedness under any
                  revolving credit facility outstanding on the date of such
                  calculation will be deemed to be (i) the average daily balance
                  of such Indebtedness during such four fiscal quarters or such
                  shorter period for which such facility was outstanding or (ii)
                  if such facility was created after the end of such four fiscal
                  quarters, the average daily balance of such Indebtedness
                  during the period from the date of creation of such facility
                  to the date of such calculation) and the discharge of any
                  other Indebtedness repaid, repurchased, defeased or otherwise
                  discharged with the proceeds of such new Indebtedness as if
                  such discharge had occurred on the first day of such period;
                  or

            (b)   has repaid, repurchased, defeased or otherwise discharged any
                  Indebtedness since the beginning of the period that is no
                  longer outstanding on such date of determination or if the
                  transaction giving rise to the need to calculate the
                  Consolidated Coverage Ratio involves a discharge of
                  Indebtedness (in each case other than Indebtedness Incurred
                  under any revolving credit facility unless such Indebtedness
                  has been permanently repaid and the related commitment
                  terminated), Consolidated


                                       20
<PAGE>
                  EBITDA and Consolidated Interest Expense for such period will
                  be calculated after giving effect on a pro forma basis to such
                  discharge of such Indebtedness, including with the proceeds of
                  such new Indebtedness, as if such discharge had occurred on
                  the first day of such period;

      (2)   if since the beginning of such period the Parent or any Restricted
            Subsidiary will have made any Asset Disposition or disposed of any
            company, division, operating unit, segment, business, group of
            related assets or line of business or if the transaction giving rise
            to the need to calculate the Consolidated Coverage Ratio is such an
            Asset Disposition:

            (a)   the Consolidated EBITDA for such period will be reduced by an
                  amount equal to the Consolidated EBITDA (if positive) directly
                  attributable to the assets which are the subject of such Asset
                  Disposition for such period or increased by an amount equal to
                  the Consolidated EBITDA (if negative) directly attributable
                  thereto for such period; and

            (b)   Consolidated Interest Expense for such period will be reduced
                  by an amount equal to the Consolidated Interest Expense
                  directly attributable to any Indebtedness of the Parent or any
                  Restricted Subsidiary repaid, repurchased, defeased or
                  otherwise discharged with respect to the Parent and its
                  continuing Restricted Subsidiaries in connection with such
                  Asset Disposition for such period (or, if the Capital Stock of
                  any Restricted Subsidiary is sold, the Consolidated Interest
                  Expense for such period directly attributable to the
                  Indebtedness of such Restricted Subsidiary to the extent the
                  Parent and its continuing Restricted Subsidiaries are no
                  longer liable for such Indebtedness after such sale);

      (3)   if since the beginning of such period the Parent or any Restricted
            Subsidiary (by merger or otherwise) will have made an Investment in
            any Restricted Subsidiary (or any Person which becomes a Restricted
            Subsidiary or is merged with or into the Parent) or an acquisition
            of assets, including any acquisition of assets occurring in
            connection with a transaction causing a calculation to be made
            hereunder, which constitutes all or substantially all of a company,
            division, operating unit, segment, business, group of related assets
            or line of business, Consolidated EBITDA and Consolidated Interest
            Expense for such period will be calculated after giving pro forma
            effect thereto (including the Incurrence of any Indebtedness) as if
            such Investment or acquisition occurred on the first day of such
            period; and

      (4)   if since the beginning of such period any Person (that subsequently
            became a Restricted Subsidiary or was merged with or into the Parent
            or any Restricted Subsidiary since the beginning of such period)
            will have Incurred any Indebtedness or discharged any Indebtedness,
            made any Asset Disposition or any Investment or acquisition of
            assets that would have required an adjustment pursuant to clause (2)
            or (3) above if made by the Parent or a Restricted Subsidiary during
            such period, Consolidated EBITDA and Consolidated Interest


                                       21
<PAGE>
            Expense for such period will be calculated after giving pro forma
            effect thereto as if such Asset Disposition or Investment or
            acquisition of assets occurred on the first day of such period.

For purposes of this definition, whenever pro forma effect is to be given to any
calculation under this definition, the pro forma calculations will be determined
in good faith by a responsible financial or accounting officer of the Parent
(including pro forma expense and cost reductions calculated on a basis
consistent with Regulation S-X under the Securities Act). If any Indebtedness
bears a floating rate of interest and is being given pro forma effect, the
interest expense on such Indebtedness will be calculated as if the rate in
effect on the date of determination had been the applicable rate for the entire
period (taking into account any Interest Rate Agreement applicable to such
Indebtedness if such Interest Rate Agreement has a remaining term in excess of
12 months). If any Indebtedness that is being given pro forma effect bears an
interest rate at the option of the Parent, the interest rate shall be calculated
by applying such optional rate chosen by the Parent.

      "Consolidated EBITDA" for any period means, without duplication, the
Consolidated Net Income for such period, plus the following to the extent
deducted in calculating such Consolidated Net Income:

      (1)   Consolidated Interest Expense;

      (2)   Consolidated Income Taxes;

      (3)   consolidated depletion and depreciation expense;

      (4)   consolidated exploration expense;

      (5)   consolidated amortization expense or impairment charges recorded in
            connection with the application of Financial Accounting Standard No.
            142 "Goodwill and Other Intangible Assets;"

      (6)   other non-cash charges reducing Consolidated Net Income (excluding
            any such non-cash charge to the extent it represents an accrual of
            or reserve for cash charges in any future period or amortization of
            a prepaid cash expense that was paid in a prior period not included
            in the calculation);

and less, to the extent included in calculating such Consolidated Net Income and
in excess of any costs or expenses attributable thereto and deducted in
calculating such Consolidated Net Income, the sum of (x) the amount of deferred
revenues that are amortized during such period and are attributable to reserves
that are subject to volumetric Production Payments, and (y) amounts recorded in
accordance with GAAP as repayments of principal and interest pursuant to
dollar-denominated Production Payments. Notwithstanding the preceding sentence,
clauses (2) through (5) relating to amounts of a Restricted Subsidiary of a
Person will be added to Consolidated Net Income to compute Consolidated EBITDA
of such Person only to the extent (and in the same proportion) that the net
income (loss) of such Restricted Subsidiary was included in calculating the
Consolidated Net Income of such Person and, to the extent the amounts set forth
in clauses (2) through (5) are in excess of those necessary to offset a net loss
of such Restricted Subsidiary


                                       22
<PAGE>
or if such Restricted Subsidiary has net income for such period included in
Consolidated Net Income, only if a corresponding amount would be permitted at
the date of determination to be dividended to the Parent by such Restricted
Subsidiary without prior approval (that has not been obtained), pursuant to the
terms of its charter and all agreements, instruments, judgments, decrees,
orders, statutes, rules and governmental regulations applicable to that
Restricted Subsidiary or its stockholders.

      "Consolidated Income Taxes" means, with respect to any Person for any
period, taxes imposed upon such Person or other payments required to be made by
such Person by any governmental authority which taxes or other payments are
calculated by reference to the income or profits of such Person or such Person
and its Restricted Subsidiaries (to the extent such income or profits were
included in computing Consolidated Net Income for such period), regardless of
whether such taxes or payments are required to be remitted to any governmental
authority.

      "Consolidated Interest Expense" means, for any period, the total interest
expense of the Parent and its consolidated Restricted Subsidiaries, whether paid
or accrued, plus, to the extent not included in such interest expense:

      (1)   interest expense attributable to Capitalized Lease Obligations and
            the interest portion of rent expense associated with Attributable
            Indebtedness in respect of the relevant lease giving rise thereto,
            determined as if such lease were a capitalized lease in accordance
            with GAAP and the interest component of any deferred payment
            obligations;

      (2)   amortization of debt discount and debt issuance cost (provided that
            any amortization of bond premium will be credited to reduce
            Consolidated Interest Expense unless, pursuant to GAAP, such
            amortization of bond premium has otherwise reduced Consolidated
            Interest Expense);

      (3)   non-cash interest expense;

      (4)   commissions, discounts and other fees and charges owed with respect
            to letters of credit and bankers' acceptance financing;

      (5)   interest actually paid by the Parent or any such Restricted
            Subsidiary under any Guarantee of Indebtedness or other obligation
            of any Person other than the Parent or any Restricted Subsidiary;

      (6)   costs associated with Interest Rate Agreements and Currency
            Agreements (including amortization of fees); provided, however, that
            if Interest Rate Agreements and Currency Agreements result in net
            benefits rather than costs, such benefits shall be credited to
            reduce Consolidated Interest Expense unless, pursuant to GAAP, such
            net benefits are otherwise reflected in Consolidated Net Income;

      (7)   the consolidated interest expense of such Person and its Restricted
            Subsidiaries that was capitalized during such period;


                                       23
<PAGE>
      (8)   all dividends paid or payable, in cash, Cash Equivalents or
            Indebtedness or accrued during such period on any series of
            Disqualified Stock of such Person or on Preferred Stock of its
            Restricted Subsidiaries payable to a party other than the Parent or
            a Wholly-Owned Subsidiary; and

      (9)   the cash contributions to any employee stock ownership plan or
            similar trust to the extent such contributions are used by such plan
            or trust to pay interest or fees to any Person (other than the
            Parent) in connection with Indebtedness Incurred by such plan or
            trust;

      provided, however, that there will be excluded therefrom any such interest
      expense of any Unrestricted Subsidiary to the extent the related
      Indebtedness is not Guaranteed or paid by the Parent or any Restricted
      Subsidiary.

For purposes of the foregoing, total interest expense will be determined (i)
after giving effect to any net payments made or received by the Parent and its
Subsidiaries with respect to Interest Rate Agreements and (ii) exclusive of
amounts classified as other comprehensive income in the balance sheet of the
Parent. Notwithstanding anything to the contrary contained herein, commissions,
discounts, yield and other fees and charges Incurred in connection with any
transaction pursuant to which the Parent or its Restricted Subsidiaries may
sell, convey or otherwise transfer or grant a security interest in any accounts
receivable or related assets shall be included in Consolidated Interest Expense.

      "Consolidated Net Income" means, for any period, the net income (loss) of
the Parent and its consolidated Restricted Subsidiaries determined in accordance
with GAAP; provided, however, that there will not be included in such
Consolidated Net Income:

      (1)   any net income (loss) of any Person if such Person is not a
            Restricted Subsidiary, except that:

            (a)   subject to the limitations contained in clauses (3), (4) and
                  (5) below, the Parent's equity in the net income of any such
                  Person for such period will be included in such Consolidated
                  Net Income up to the aggregate amount of cash actually
                  distributed by such Person during such period to the Parent or
                  a Restricted Subsidiary as a dividend or other distribution
                  (subject, in the case of a dividend or other distribution to a
                  Restricted Subsidiary, to the limitations contained in clause
                  (2) below); and

            (b)   the Parent's equity in a net loss of any such Person (other
                  than an Unrestricted Subsidiary) for such period will be
                  included in determining such Consolidated Net Income to the
                  extent such loss has been funded with cash from the Parent or
                  a Restricted Subsidiary;

      (2)   any net income (but not loss) of any Restricted Subsidiary if such
            Subsidiary is subject to restrictions, directly or indirectly, on
            the payment of dividends or the making of distributions by such
            Restricted Subsidiary, directly or indirectly, to the Parent, except
            that:


                                       24
<PAGE>
            (a)   subject to the limitations contained in clauses (3), (4) and
                  (5) below, the Parent's equity in the net income of any such
                  Restricted Subsidiary for such period will be included in such
                  Consolidated Net Income up to the aggregate amount of cash
                  that could have been distributed by such Restricted Subsidiary
                  during such period to the Parent or another Restricted
                  Subsidiary as a dividend (subject, in the case of a dividend
                  to another Restricted Subsidiary, to the limitation contained
                  in this clause); and

            (b)   the Parent's equity in a net loss of any such Restricted
                  Subsidiary for such period will be included in determining
                  such Consolidated Net Income;

      (3)   any gain (loss) realized upon the sale or other disposition of any
            property, plant or equipment of the Parent or its consolidated
            Restricted Subsidiaries (including pursuant to any Sale/Leaseback
            Transaction) which is not sold or otherwise disposed of in the
            ordinary course of business and any gain (loss) realized upon the
            sale or other disposition of any Capital Stock of any Person;

      (4)   any extraordinary gain or loss;

      (5)   the cumulative effect of a change in accounting principles;

      (6)   any non-cash mark-to-market adjustments to assets or liabilities
            resulting in unrealized gains or losses in respect of Hedging
            Obligations (including those resulting from the application of SFAS
            133); and

      (7)   any impairments or write-downs of oil and natural gas assets;
            provided, however, that, to the extent they may become applicable,
            ceiling limitation write-downs in accordance with generally accepted
            accounting principles shall be treated as capitalized costs, as if
            such write-downs had not occurred.

      "Corporate Trust Office" means when used with respect to (i) the Trustee,
the principal corporate trust office which as of the date of this Indenture is
located at 950 17th Street, Suite 300, Denver, Colorado 80202, provided that
with respect to payments on the Notes and exchange, transfer, or surrender of
the Notes, means c/o U.S. Bank National Association, 60 Livingston Avenue, St.
Paul, Minnesota 55107 or such other location designated in writing by the
Trustee; (ii) any Paying Agent other than the Trustee, such office as is
designated in writing to the Trustee.

      "Credit Facility" means, with respect to the Parent and any of its
Restricted Subsidiaries, one or more debt facilities (including, with
limitation, the Existing Credit Facilities) or commercial paper facilities with
banks or other institutional lenders providing for revolving credit loans, term
loans, receivables financing (including through the sale of receivables to such
lenders or to special purpose entities formed to borrow from such lenders
against such receivables), accounts payable overdraft financing or letters of
credit, in each case, as amended, restated, modified, renewed, refunded,
replaced or refinanced in whole or in part from time to time (and whether or not
with the original administrative agent and lenders or another


                                       25
<PAGE>
administrative agent or agents or other lenders and whether provided under the
Existing Credit Facilities or any other credit or other agreement or indenture).

      "Currency Agreement" means in respect of a Person any foreign exchange
contract, currency swap agreement, futures contract, option contract or other
similar agreement as to which such Person is a party or a beneficiary.

      "Custodian" means any receiver, trustee, assignee, liquidator, custodian
or similar official under any Bankruptcy Law.

      "Default" means any event which is, or after notice or passage of time or
both would be, an Event of Default.

      "Definitive Securities" means certificated Parent Notes, Subsidiary Notes
and Units.

      "Designated Senior Indebtedness" means (1) the Bank Indebtedness (to the
extent such Bank Indebtedness constitutes Senior Indebtedness) and (2) any other
Senior Indebtedness which, at the date of determination, has an aggregate
principal amount outstanding of, or under which, at the date of determination,
the holders thereof are committed to lend up to, at least $25 million and is
specifically designated in the instrument evidencing or governing such Senior
Indebtedness as "Designated Senior Indebtedness" for purposes of this Indenture.

      "Disqualified Stock" means, with respect to any Person, any Capital Stock
of such Person which by its terms (or by the terms of any security into which it
is convertible or for which it is exchangeable) or upon the happening of any
event:

      (1)   matures or is mandatorily redeemable pursuant to a sinking fund
            obligation or otherwise;

      (2)   is convertible or exchangeable for Indebtedness or Disqualified
            Stock (excluding Capital Stock which is convertible or exchangeable
            solely at the option of the Parent or a Restricted Subsidiary); or

      (3)   is redeemable at the option of the holder of the Capital Stock in
            whole or in part,

in each case on or prior to the date that is 91 days after the earlier of the
date (a) of the Stated Maturity of the Notes or (b) on which there are no Units
outstanding, provided that only the portion of Capital Stock which so matures or
is mandatorily redeemable, is so convertible or exchangeable or is so redeemable
at the option of the holder thereof prior to such date will be deemed to be
Disqualified Stock; provided, further that any Capital Stock that would
constitute Disqualified Stock solely because the holders thereof have the right
to require the Parent to repurchase such Capital Stock upon the occurrence of a
change of control or asset sale (each defined in a substantially identical
manner to the corresponding definitions in this Indenture) shall not constitute
Disqualified Stock if the terms of such Capital Stock (and all such securities
into which it is convertible or for which it is ratable or exchangeable) provide
that the Parent may not repurchase or redeem any such Capital Stock (and all
such securities into which it is convertible or for which it is ratable or
exchangeable) pursuant to such provision prior to


                                       26
<PAGE>
compliance by the Parent with Section 1009 and Section 1017 and such repurchase
or redemption complies with Section 1005.

      "Equity Offering" means a public or private sale for cash by the Parent of
its Common Stock, or options, warrants or rights with respect to its Common
Stock, other than public offerings with respect to the Parent's Common Stock, or
options, warrants or rights, registered on Form S-4 or S-8.

      "Exchange Act" means the Securities Exchange Act of 1934 and any successor
statute thereto, in each case as amended from time to time.

      "Existing Credit Facilities" means:

      (1)   the Credit Agreement, dated as of June 27, 2003, among the Parent,
            the lenders party thereto, the other agents party thereto, BNP
            Paribas, Wachovia Bank, National Association and The Bank of Nova
            Scotia, as Global Syndication Agents, U.S. Bank National
            Association, as U.S. Documentation Agent, and JPMorgan Chase Bank,
            as Global Administrative Agent;

      (2)   the Credit Agreement, dated as of June 27, 2003, among the
            Subsidiary Issuer, Tom Brown Resources Ltd., the lenders party
            thereto, the other agents party thereto, National Bank of Canada, as
            Canadian Revolving Documentation Agent, JPMorgan Chase Bank Toronto
            Branch, as Canadian Administrative Agent, and JPMorgan Chase Bank,
            as Global Administrative Agent;

      (3)   the Credit Agreement, dated March 20, 2001, as amended by the First
            Amendment thereto dated as of June 27, 2003, by and among the
            Subsidiary Issuer, the lenders party thereto, JPMorgan Chase Bank,
            as global administrative agent, JPMorgan Chase Bank, Toronto Branch,
            as Canadian administrative agent , and the other agents and lenders
            party thereto; and

      (4)   the Credit Facility, dated as of April 6, 2001, by and between Tom
            Brown Resources Ltd. and National Bank of Canada.

      "Foreign Subsidiary" means any Restricted Subsidiary that is not organized
under the laws of the United States of America or any state thereof or the
District of Columbia.

      "GAAP" means generally accepted accounting principles in the United States
of America as in effect as of the date of this Indenture, including those set
forth in the opinions and pronouncements of the Accounting Principles Board of
the American Institute of Certified Public Accountants and statements and
pronouncements of the Financial Accounting Standards Board or in such other
statements by such other entity as approved by a significant segment of the
accounting profession. All ratios and computations based on GAAP contained in
this Indenture will be computed in conformity with GAAP.

      "Guarantee" means any obligation, contingent or otherwise, of any Person
directly or indirectly guaranteeing any Indebtedness of any other Person and any
obligation, direct or indirect, contingent or otherwise, of such Person:


                                       27
<PAGE>
      (1)   to purchase or pay (or advance or supply funds for the purchase or
            payment of) such Indebtedness of such other Person (whether arising
            by virtue of partnership arrangements, or by agreement to keep-well,
            to purchase assets, goods, securities or services, to take-or-pay,
            or to maintain financial statement conditions or otherwise); or

      (2)   entered into for purposes of assuring in any other manner the
            obligee of such Indebtedness of the payment thereof or to protect
            such obligee against loss in respect thereof (in whole or in part);

provided, however, that the term "Guarantee" will not include endorsements for
collection or deposit in the ordinary course of business or Liens of the Capital
Stock or assets of a Restricted Subsidiary constituting Permitted Liens under
clause (1) of the definition of "Permitted Liens." The term "Guarantee" used as
a verb has a corresponding meaning.

      "Hedging Obligations" of any Person means the obligations of such Person
pursuant to any Interest Rate Agreement, Currency Agreement or Commodity
Agreement.

      "Holder" means the Person in whose name a Parent Note, Subsidiary Note or
Unit, as the case may be, is registered in the Register.

      "Hydrocarbon Interests" means all rights, titles and interests in and to
oil and gas leases, oil, gas and mineral leases, other Hydrocarbon leases,
mineral interests, mineral servitudes, overriding royalty interests, royalty
interests, net profits interests, Production Payments, and other similar
interests.

      "Hydrocarbons" means, collectively, oil, gas, casinghead gas, drip
gasoline, natural gasoline, condensate, distillate and all other liquid or
gaseous hydrocarbons and related minerals and all products therefrom, in each
case whether in a natural or a processed state.

      "Incur" means issue, create, assume, Guarantee, incur or otherwise become
liable for; provided, however, that any Indebtedness or Capital Stock of a
Person existing at the time such person becomes a Restricted Subsidiary (whether
by merger, consolidation, acquisition or otherwise) will be deemed to be
Incurred by such Restricted Subsidiary at the time it becomes a Restricted
Subsidiary; and the terms "Incurred" and "Incurrence" have meanings correlative
to the foregoing.

      "Indebtedness" means, with respect to any Person on any date of
determination (without duplication):

      (1)   the principal of and premium (if any) in respect of indebtedness of
            such Person for borrowed money;

      (2)   the principal of and premium (if any) in respect of obligations of
            such Person evidenced by bonds, debentures, notes or other similar
            instruments;

      (3)   the principal component of all obligations of such Person in respect
            of letters of credit, bankers' acceptances or other similar
            instruments (including


                                       28
<PAGE>
            reimbursement obligations with respect thereto except to the extent
            such reimbursement obligation relates to a trade payable and such
            obligation is satisfied within 30 days of Incurrence);

      (4)   the principal component of all obligations of such Person to pay the
            deferred and unpaid purchase price of property (except trade
            payables), which purchase price is due more than six months after
            the date of placing such property in service or taking delivery and
            title thereto;

      (5)   Capitalized Lease Obligations and all Attributable Indebtedness of
            such Person;

      (6)   the principal component or liquidation preference of all obligations
            of such Person with respect to the redemption, repayment or other
            repurchase of any Disqualified Stock or, with respect to any
            Subsidiary, any Preferred Stock (but excluding, in each case, any
            accrued dividends);

      (7)   the principal component of all Indebtedness of other Persons secured
            by a Lien on any asset of such Person, whether or not such
            Indebtedness is assumed by such Person; provided, however, that the
            amount of such Indebtedness will be the lesser of (a) the fair
            market value of such asset at such date of determination and (b) the
            amount of such Indebtedness of such other Persons;

      (8)   the principal component of Indebtedness of other Persons to the
            extent Guaranteed by such Person (including any Guarantees of
            production or payment by such Person with respect to a Production
            Payment but excluding other contractual obligations of such Person
            with respect to such Production Payment); and

      (9)   to the extent not otherwise included in this definition, net
            obligations of such Person under Currency Agreements and Interest
            Rate Agreements (the amount of any such obligations to be equal at
            any time to the termination value of such agreement or arrangement
            giving rise to such obligation that would be payable by such Person
            at such time).

The amount of Indebtedness of any Person at any date will be the outstanding
balance at such date of all unconditional obligations as described above and the
maximum liability, upon the occurrence of the contingency giving rise to the
obligation, of any contingent obligations at such date.

      Notwithstanding the foregoing, the following shall not constitute
"Indebtedness":

      (1)   any obligation in respect of any Production Payment (except as set
            forth in clause (8) of the first paragraph of this definition of
            "Indebtedness"), royalty, overriding royalty, net profits interest,
            master limited partnership interest or other interest in oil and
            natural gas properties, reserves or the right to receive all or a
            portion of the production or the proceeds from the sale of
            production attributable to such properties;


                                       29
<PAGE>
      (2)   any obligation in respect of a farm-in agreement;

      (3)   any indebtedness which has been defeased in accordance with GAAP or
            defeased pursuant to the deposit of cash or U.S. Government
            Obligations (in an amount sufficient to satisfy all such
            indebtedness obligations at maturity or redemption, as applicable,
            and all payments of interest and premium, if any) in a trust or
            account created or pledged for the sole benefit of the holders of
            such indebtedness, and subject to no other Liens, and the other
            applicable terms of the instrument governing such indebtedness;

      (4)   oil or gas balancing liabilities incurred in the ordinary course of
            business and consistent with past practice;

      (5)   any obligations in respect of completion bonds, performance bonds,
            bid bonds, appeal bonds, surety bonds, bankers acceptances, letters
            of credit, insurance obligations or bonds and other similar bonds
            and obligations incurred by the Parent or any Restricted Subsidiary
            in the ordinary course of business and any guaranties or letters of
            credit functioning as or supporting any of the foregoing bonds or
            obligations;

      (6)   any obligation under Interest Rate Agreements, Currency Agreements
            and Commodity Agreements; provided, that such Interest Rate
            Agreements, Currency Agreements and Commodity Agreements are related
            to business transactions of the Parent or its Restricted
            Subsidiaries entered into in the ordinary course of business and are
            entered into for bona fide hedging purposes of the Parent or its
            Restricted Subsidiaries (as determined in good faith by the Board of
            Directors or senior management of the Parent);

      (7)   any obligation arising from agreements of the Parent or a Restricted
            Subsidiary providing for indemnification, guarantee, adjustment of
            purchase price, holdback, contingency payment obligation based on
            the performance of the disposed asset or similar obligations, in
            each case, Incurred or assumed in connection with the disposition of
            any business, assets or Capital Stock of a Restricted Subsidiary,
            provided that the maximum aggregate liability in respect of all such
            Indebtedness shall at no time exceed the gross proceeds actually
            received by the Parent and its Restricted Subsidiaries in connection
            with such disposition; and

      (8)   any obligation arising from the honoring by a bank or other
            financial institution of a check, draft or similar instrument
            (except in the case of daylight overdrafts) drawn against
            insufficient funds in the ordinary course of business, provided,
            however, that such Indebtedness is extinguished within five Business
            Days of Incurrence.

      "Interest Payment Date", when used with respect to any security, means the
Stated Maturity of an installment of interest on such security.

      "Interest Rate Agreement" means with respect to any Person any interest
rate protection agreement, interest rate future agreement, interest rate option
agreement, interest rate swap


                                       30
<PAGE>
agreement, interest rate cap agreement, interest rate collar agreement, interest
rate hedge agreement or other similar agreement or arrangement as to which such
Person is party or a beneficiary.

      "Investment" means, with respect to any Person, all investments by such
Person in other Persons (including Affiliates) in the form of any direct or
indirect advance, loan (other than advances or extensions of credit to customers
in the ordinary course of business) or other extensions of credit (including by
way of Guarantee or similar arrangement, but excluding any debt or extension of
credit represented by a bank deposit other than a time deposit) or capital
contribution to (by means of any transfer of cash or other property to others or
any payment for property or services for the account or use of others), or any
purchase or acquisition of Capital Stock, Indebtedness or other similar
instruments issued by, such Person and all other items that are or would be
classified as investments on a balance sheet prepared in accordance with GAAP;
provided that none of the following will be deemed to be an Investment:

      (1)   Hedging Obligations entered into in the ordinary course of business
            and in compliance with this Indenture;

      (2)   endorsements of negotiable instruments and documents in the ordinary
            course of business; and

      (3)   an acquisition of assets, Capital Stock or other securities by the
            Parent or a Subsidiary for consideration to the extent such
            consideration consists of common equity securities of the Parent.

      For purposes of Section 1005,

      (1)   "Investment" will include the portion (proportionate to the Parent's
            equity interest in a Restricted Subsidiary to be designated as an
            Unrestricted Subsidiary) of the fair market value of the net assets
            of such Restricted Subsidiary of the Parent at the time that such
            Restricted Subsidiary is designated an Unrestricted Subsidiary;
            provided, however, that upon a redesignation of such Subsidiary as a
            Restricted Subsidiary, the Parent will be deemed to continue to have
            a permanent "Investment" in an Unrestricted Subsidiary in an amount
            (if positive) equal to (a) the Parent's "Investment" in such
            Subsidiary at the time of such redesignation less (b) the portion
            (proportionate to the Parent's equity interest in such Subsidiary)
            of the fair market value of the net assets (as conclusively
            determined by the Board of Directors of the Parent in good faith) of
            such Subsidiary at the time that such Subsidiary is so re-designated
            a Restricted Subsidiary; and

      (2)   any property transferred to or from an Unrestricted Subsidiary will
            be valued at its fair market value at the time of such transfer, in
            each case as determined in good faith by the Board of Directors of
            the Parent. If the Parent or any Restricted Subsidiary of the Parent
            sells or otherwise disposes of any Voting Stock of any Restricted
            Subsidiary of the Parent such that, after giving effect to any such
            sale or disposition, such entity is no longer a Subsidiary of the
            Parent, the Parent shall be deemed to have made an Investment on the
            date of any such sale or disposition


                                       31
<PAGE>
            equal to the fair market value (as conclusively determined by the
            Board of Directors of the Parent in good faith) of the Capital Stock
            of such Subsidiary not sold or disposed of.

      "Investment Grade Rating" means a rating equal to or higher than Baa3 (or
the equivalent) by Moody's or BBB- (or the equivalent) by S&P.

      "Issue Date" means the date on which the Notes and the Units are
originally issued.

      "Lien" means any mortgage, pledge, security interest, encumbrance, lien or
charge of any kind (including any conditional sale or other title retention
agreement or lease in the nature thereof).

      "Moody's" means Moody's Investors Service, Inc. or any successor to the
rating agency business thereof.

      "Net Available Cash" from an Asset Disposition means cash payments
received (including any cash payments received by way of deferred payment of
principal pursuant to a note or installment receivable or otherwise and net
proceeds from the sale or other disposition of any securities received as
consideration, but only as and when received, but excluding any other
consideration received in the form of assumption by the acquiring person of
Indebtedness or other obligations relating to the properties or assets that are
the subject of such Asset Disposition or received in any other non-cash form)
therefrom, in each case net of:

      (1)   all legal, accounting, investment banking, title and recording tax
            expenses, commissions and other fees and expenses Incurred, and all
            Federal, state, provincial, foreign and local taxes required to be
            paid or accrued as a liability under GAAP (after taking into account
            any available tax credits or deductions and any tax sharing
            agreements), as a consequence of such Asset Disposition;

      (2)   all payments made on any Indebtedness which is secured by any assets
            subject to such Asset Disposition, in accordance with the terms of
            any Lien upon such assets, or which must by its terms, or in order
            to obtain a necessary consent to such Asset Disposition, or by
            applicable law be repaid out of the proceeds from such Asset
            Disposition;

      (3)   all distributions and other payments required to be made to minority
            interest holders in Subsidiaries or joint ventures as a result of
            such Asset Disposition; and

      (4)   the deduction of appropriate amounts to be provided by the seller as
            a reserve, in accordance with GAAP, against any liabilities
            associated with the assets disposed of in such Asset Disposition and
            retained by the Parent or any Restricted Subsidiary after such Asset
            Disposition.

      "Net Cash Proceeds," with respect to any issuance or sale of Capital
Stock, means the cash proceeds of such issuance or sale net of attorneys' fees,
accountants' fees, underwriters' or placement agents' fees, listing fees,
discounts or commissions and brokerage, consultant and other fees and charges
actually Incurred in connection with such issuance or sale and net of taxes


                                       32
<PAGE>
paid or payable as a result of such issuance or sale (after taking into account
any available tax credit or deductions and any tax sharing arrangements).

      "Net Working Capital" means:

      (1)   all current assets of the Parent and its Restricted Subsidiaries;
            minus

      (2)   all current liabilities of the Parent and its Restricted
            Subsidiaries, except current liabilities included in Indebtedness;

determined in accordance with GAAP.

      "Non-Recourse Debt" means Indebtedness of a Person:

      (1)   as to which neither the Parent nor any Restricted Subsidiary (a)
            provides any Guarantee or credit support of any kind (including any
            undertaking, guarantee, indemnity, agreement or instrument that
            would constitute Indebtedness) or (b) is directly or indirectly
            liable (as a guarantor or otherwise);

      (2)   no default with respect to which (including any rights that the
            holders thereof may have to take enforcement action against an
            Unrestricted Subsidiary) would permit (upon notice, lapse of time or
            both) any holder of any other Indebtedness of the Parent or any
            Restricted Subsidiary to declare a default under such other
            Indebtedness or cause the payment thereof to be accelerated or
            payable prior to its stated maturity; and

      (3)   the explicit terms of which provide there is no recourse against any
            of the assets of the Parent or its Restricted Subsidiaries.

      "Officer" means the Chairman of the Board, the Chief Executive Officer,
the President, the Chief Financial Officer, any Vice President, the Treasurer or
the Secretary of the Parent.

      "Officers' Certificate" means a certificate signed by two Officers or by
an Officer and either an Assistant Treasurer or an Assistant Secretary of the
Parent.

      "Oil and Gas Business" means:

      (1)   the acquisition, exploration, exploitation, development, operation
            or disposition of interests in oil, gas or other hydrocarbon
            properties;

      (2)   the gathering, marketing, treating, processing, storage, selling,
            transporting or refining of any production from such interests or
            properties;

      (3)   any business relating to or arising from exploration for or
            development, production, gathering, marketing, treatment,
            processing, storage, sale, transportation or refining of oil, gas
            and other minerals and products produced in association therewith;
            or


                                       33
<PAGE>
      (4)   any activity that is ancillary or necessary or desirable to
            facilitate the activities described in clauses (1) through (3) of
            this definition, including raising capital to finance its
            operations.

      "Oil and Gas Properties" means the Hydrocarbon Interests; the Properties
now or hereafter pooled or unitized with the Hydrocarbon Interests; all
presently existing or future unitization, pooling agreements and declarations of
pooled units and the units created thereby (including without limitation all
units created under orders, regulations and rules of any governmental authority
having jurisdiction) which may affect all or any portion of the Hydrocarbon
Interests; all operating agreements, joint venture agreements, contracts and
other agreements which relate to any of the Hydrocarbon Interests or the
production, sale, purchase, exchange or processing of Hydrocarbons from or
attributable to such Hydrocarbon Interests; all Hydrocarbons in and under and
which may be produced and saved or attributable to the Hydrocarbon Interests,
the lands covered thereby and all oil in tanks and all rents, issues, profits,
proceeds, products, revenues and other incomes from or attributable to the
Hydrocarbon Interests; all tenements, profits a prendre, hereditaments,
appurtenances and Properties in anywise appertaining, belonging, affixed or
incidental to the Hydrocarbon Interests, Properties, rights, titles, interests
and estates described or referred to above, including any and all Property, real
or personal, now owned or hereinafter acquired and situated upon, used, held for
use or useful in connection with the operating, working or development of any of
such Hydrocarbon Interests or Property (excluding drilling rigs, automotive
equipment or other personal Property which may be on such premises for the
purpose of drilling a well or for other similar temporary uses) and including
any and all oil wells, gas wells, water wells, injection wells or other wells,
buildings, structures, fuel separators, liquid extraction plants, plant
compressors, pumps, pumping units, field gathering systems, tanks and tank
batteries, fixtures, valves, fittings, machinery and parts, engines, boilers,
meters, apparatus, equipment, appliances, tools, implements, cables, wires,
towers, casing, tubing and rods, surface leases, rights-of-way, easements and
servitudes together with all additions, substitutions, replacements, accessions
and attachments to any and all of the foregoing.

      "Opinion of Counsel" means a written opinion from legal counsel who is
acceptable to the Trustee. The counsel may be an employee of or counsel to the
Parent or the Trustee.

      "Permitted Business Investments" means Investments and expenditures made
in the ordinary course of, and of a nature that is or shall have become
customary in, the Oil and Gas Business as means of actively exploiting,
exploring for, acquiring, developing, processing, gathering, marketing or
transporting oil, natural gas, other hydrocarbons and minerals through
agreements, transactions, interests or arrangements that permit one to share
risks or costs, comply with regulatory requirements regarding local ownership or
satisfy other objectives customarily achieved through the conduct of the Oil and
Gas Business jointly with third parties, including without limitation:

      (1)   ownership interests in oil, natural gas, other hydrocarbons and
            minerals properties or gathering, transportation, processing,
            storage or related systems; and

      (2)   Investment in the form of or pursuant to operating agreements, joint
            venture agreements, partnership agreements, processing agreements,
            farm-in agreements,


                                       34
<PAGE>
            farm-out agreements, contracts for the sale, transportation or
            exchange of oil, natural gas and other hydrocarbons, unitization
            agreements, pooling arrangements, joint bidding agreements, service
            contracts, subscription agreements, stock purchase agreements, area
            of mutual interest agreements, production sharing agreements or
            other similar or customary agreements with third parties, excluding,
            however, Investments in corporations other than Restricted
            Subsidiaries.

      "Permitted Investment" means an Investment by the Parent or any Restricted
Subsidiary in:

      (1)   a Restricted Subsidiary or a Person which will, upon the making of
            such Investment, become a Restricted Subsidiary; provided, however,
            that the primary business of such Restricted Subsidiary is the Oil
            and Gas Business;

      (2)   another Person if as a result of such Investment such other Person
            is merged or consolidated with or into, or transfers or conveys all
            or substantially all its assets to, the Parent or a Restricted
            Subsidiary; provided, however, that such Person's primary business
            is the Oil and Gas Business;

      (3)   Permitted Business Investments;

      (4)   cash and Cash Equivalents;

      (5)   receivables owing to the Parent or any Restricted Subsidiary created
            or acquired in the ordinary course of business and payable or
            dischargeable in accordance with customary trade terms; provided,
            however, that such trade terms may include such concessionary trade
            terms as the Parent or any such Restricted Subsidiary deems
            reasonable under the circumstances;

      (6)   payroll, travel and similar advances to cover matters that are
            expected at the time of such advances ultimately to be treated as
            expenses for accounting purposes and that are made in the ordinary
            course of business;

      (7)   loans or advances to employees (other than executive officers) made
            in the ordinary course of business consistent with past practices of
            the Parent or such Restricted Subsidiary;

      (8)   Capital Stock, obligations or securities received in settlement of
            debts created in the ordinary course of business and owing to the
            Parent or any Restricted Subsidiary or in satisfaction of judgments
            or pursuant to any plan of reorganization or similar arrangement
            upon the bankruptcy or insolvency of a debtor;

      (9)   Investments made as a result of the receipt of non-cash
            consideration from an Asset Disposition that was made pursuant to
            and in compliance with Section 1009;


                                       35
<PAGE>
      (10)  Investments for consideration consisting of Capital Stock (other
            than Disqualified Stock) of the Parent;

      (11)  Investments in existence on the Issue Date;

      (12)  Currency Agreements, Interest Rate Agreements, Commodity Agreements
            and related Hedging Obligations, which transactions or obligations
            are Incurred in compliance with Section 1004;

      (13)  Investments by the Parent or any of its Restricted Subsidiaries,
            together with all other Investments pursuant to this clause (13), in
            an aggregate amount at the time of such Investment not to exceed $15
            million outstanding at any one time (with the fair market value of
            such Investment being measured at the time made and without giving
            effect to subsequent changes in value);

      (14)  Guarantees issued in accordance with Section 1004;

      (15)  prepaid expenses, lease, utilities, workers' compensation
            performance and similar deposits made in the ordinary course of
            business;

      (16)  Investments owned by a Person if and when it is acquired by the
            Parent and becomes a Restricted Subsidiary; provided, however, that
            such Investments are not made in contemplation of such acquisition;

      (17)  Investments in any units of any oil and gas royalty trust; and

      (18)  any Asset Swap made in accordance with Section 1009(g).

      "Permitted Liens" means, with respect to any Person:

      (1)   Liens securing Indebtedness and other obligations under the Credit
            Facility and related Hedging Obligations and other Senior
            Indebtedness and liens on assets of Restricted Subsidiaries securing
            Guarantees of Indebtedness and other obligations under the Credit
            Facility permitted to be Incurred under this Indenture;

      (2)   pledges or deposits by such Person under workmen's compensation
            laws, unemployment insurance laws or similar legislation, or good
            faith deposits in connection with bids, tenders, contracts (other
            than for the payment of Indebtedness) or leases to which such Person
            is a party, or deposits to secure public or statutory obligations of
            such Person or deposits or cash or United States government bonds to
            secure surety or appeal bonds to which such Person is a party, or
            deposits as security for contested taxes or import or customs duties
            or for the payment of rent, in each case Incurred in the ordinary
            course of business;

      (3)   Liens imposed by law, including carriers', warehousemen's and
            mechanics' Liens, in each case for sums not yet due or being
            contested in good faith by appropriate proceedings if a reserve or
            other appropriate provisions, if any, as shall be required by GAAP
            shall have been made in respect thereof;


                                       36
<PAGE>
      (4)   Liens for taxes, assessments or other governmental charges not yet
            subject to penalties for non-payment or which are being contested in
            good faith by appropriate proceedings provided appropriate reserves
            required pursuant to GAAP have been made in respect thereof;

      (5)   Liens in favor of issuers of surety or performance bonds or letters
            of credit or bankers' acceptances issued pursuant to the request of
            and for the account of such Person in the ordinary course of its
            business; provided, however, that such letters of credit do not
            constitute Indebtedness;

      (6)   encumbrances, ground leases, easements or reservations of, or rights
            of others for, licenses, rights of way, sewers, electric lines,
            telegraph and telephone lines and other similar purposes, or zoning,
            building codes or other restrictions as to the use of real
            properties or liens incidental to the conduct of the business of
            such Person or to the ownership of its properties which do not in
            the aggregate materially adversely affect the value of said
            properties or materially impair their use in the operation of the
            business of such Person;

      (7)   Liens securing Hedging Obligations;

      (8)   leases, licenses, subleases and sublicenses of assets which do not
            materially interfere with the ordinary conduct of the business of
            the Parent or any of its Restricted Subsidiaries;

      (9)   judgment Liens not giving rise to an Event of Default so long as
            such Lien is adequately bonded and any appropriate legal proceedings
            which may have been duly initiated for the review of such judgment
            have not been finally terminated or the period within which such
            proceedings may be initiated has not expired;

      (10)  Liens for the purpose of securing the payment of all or a part of
            the purchase price of, or Capitalized Lease Obligations, purchase
            money obligations or other payments Incurred to finance the
            acquisition, improvement or construction of, assets or property
            acquired or constructed in the ordinary course of business provided
            that:

            (a)   the aggregate principal amount of Indebtedness secured by such
                  Liens is otherwise permitted to be Incurred under this
                  Indenture and does not exceed the cost of the assets or
                  property so acquired or constructed; and

            (b)   such Liens are created within 180 days of construction or
                  acquisition of such assets or property and do not encumber any
                  other assets or property of the Parent or any Restricted
                  Subsidiary other than such assets or property and assets
                  affixed or appurtenant thereto;

      (11)  Liens arising solely by virtue of any statutory or common law
            provisions relating to banker's Liens, rights of set-off or similar
            rights and remedies as to deposit accounts or other funds maintained
            with a depositary institution; provided that:


                                       37
<PAGE>
            (a)   such deposit account is not a dedicated cash collateral
                  account and is not subject to restrictions against access by
                  the Parent in excess of those set forth by regulations
                  promulgated by the U.S. Federal Reserve Board; and

            (b)   such deposit account is not intended by the Parent or any
                  Restricted Subsidiary to provide collateral to the depository
                  institution;

      (12)  Liens arising from Uniform Commercial Code financing statement
            filings regarding operating leases entered into by the Parent and
            its Restricted Subsidiaries in the ordinary course of business;

      (13)  Liens existing on the Issue Date;

      (14)  Liens in favor of the Parent or the Subsidiary Issuer;

      (15)  Liens on property or shares of stock of a Person at the time such
            Person becomes a Restricted Subsidiary; provided, however, that such
            Liens are not created, Incurred or assumed in connection with, or in
            contemplation of, such other Person becoming a Restricted
            Subsidiary; provided further, however, that any such Lien may not
            extend to any other property owned by the Parent or any Restricted
            Subsidiary;

      (16)  Liens on property at the time the Parent or a Restricted Subsidiary
            acquired the property, including any acquisition by means of a
            merger or consolidation with or into the Parent or any Restricted
            Subsidiary; provided, however, that such Liens are not created,
            Incurred or assumed in connection with, or in contemplation of, such
            acquisition; provided further, however, that such Liens may not
            extend to any other property owned by the Parent or any Restricted
            Subsidiary;

      (17)  Liens securing Indebtedness or other obligations of a Restricted
            Subsidiary owing to the Parent or another Restricted Subsidiary;

      (18)  Liens securing the Notes and other obligations arising under this
            Indenture;

      (19)  Liens securing Refinancing Indebtedness Incurred to refinance
            Indebtedness that was previously so secured, provided that any such
            Lien is limited to all or part of the same property or assets (plus
            improvements, accessions, proceeds or dividends or distributions in
            respect thereof) that secured (or, under the written arrangements
            under which the original Lien arose, could secure) the Indebtedness
            being refinanced or is in respect of property that is the security
            for a Permitted Lien hereunder;

      (20)  any interest or title of a lessor under any Capitalized Lease
            Obligation or operating lease; and

      (21)  Liens on pipelines and pipeline facilities that arise by operation
            of law;


                                       38
<PAGE>
      (22)  farm-out, carried working interest, joint operating, unitization,
            royalty, sales and similar agreements relating to the exploration or
            development of, or production from, Oil and Gas Properties entered
            into in the ordinary course of business;

      (23)  Liens arising under operating agreements, joint venture agreements,
            partnership agreements, oil and gas leases, farm-in agreements,
            farm-out agreements, assignments, purchase and sale agreements,
            division orders, contracts for the sale, purchase, processing,
            transportation or exchange of oil or natural gas, unitization and
            pooling declarations and agreements, development agreements, area of
            mutual interest agreements and other agreements that are customary
            in the Oil and Gas Business;

      (24)  Liens reserved in oil and gas mineral leases for bonus, royalty or
            rental payments and for compliance with the terms of such leases,

      (25)  leases, pooling agreements, unitization agreements, subleases,
            licenses or sublicenses, joint interest billing arrangements, net
            profits interests, participation agreements, and arrangements
            similar to any of the foregoing, entered into in the ordinary course
            of business;

      (26)  Liens to secure Production Payments that are not prohibited by this
            Indenture; and

      (27)  Liens incurred in the ordinary course of business of the Parent and
            its Subsidiaries with respect to obligations that do not exceed $10
            million.

      "Person" means any individual, corporation, partnership, joint venture,
association, joint-stock company, trust, unincorporated organization, limited
liability company, government or any agency or political subdivision hereof or
any other entity.

      "Preferred Stock," as applied to the Capital Stock of any corporation,
means Capital Stock of any class or classes (however designated) which is
preferred as to the payment of dividends, or as to the distribution of assets
upon any voluntary or involuntary liquidation or dissolution of such
corporation, over shares of Capital Stock of any other class of such
corporation.

      "Production Payments" means a production payment obligation (whether
volumetric or U. S. dollar-denominated) of the Parent or any of its Subsidiaries
which are payable from a specified share of proceeds received from production
from specified Oil and Gas Properties, together with all undertakings and
obligations in connection therewith.

      "Property" or "property" means any interest in any kind of property or
asset, whether real, personal or mixed, or tangible or intangible.

      A "Public Market" exists at any time with respect to the Common Stock of
the Parent if the Common Stock of the Parent is then registered with SEC
pursuant to Section 12(b) or 12(g) of Exchange Act and traded either on a
national securities exchange or in the Nasdaq Stock Market.


                                       39
<PAGE>
      "Redemption Date", when used with respect to any Note or Unit to be
redeemed, means the date fixed for such redemption by or pursuant to this
Indenture.

      "Redemption Price", when used with respect to any Note or Unit to be
redeemed, means the price at which it is to be redeemed pursuant to this
Indenture.

      "Refinancing Indebtedness" means Indebtedness that is Incurred to refund,
refinance, replace, exchange, renew, repay or extend (including pursuant to any
defeasance or discharge mechanism) (collectively, "refinance," "refinances," and
"refinanced" shall have a correlative meaning) any Indebtedness existing on the
date of this Indenture or Incurred in compliance with this Indenture (including
Indebtedness of the Parent that refinances Indebtedness of any Restricted
Subsidiary and Indebtedness of any Restricted Subsidiary that refinances
Indebtedness of another Restricted Subsidiary) including Indebtedness that
refinances Refinancing Indebtedness, provided, however, that:

      (1)   (a) if the Stated Maturity of the Indebtedness being refinanced is
            earlier than the Stated Maturity of the Notes, the Refinancing
            Indebtedness has a Stated Maturity no earlier than the Stated
            Maturity of the Indebtedness being refinanced or (b) if the Stated
            Maturity of the Indebtedness being refinanced is later than the
            Stated Maturity of the Notes, the Refinancing Indebtedness has a
            Stated Maturity at least 91 days later than the Stated Maturity of
            the Notes;

      (2)   the Refinancing Indebtedness has an Average Life at the time such
            Refinancing Indebtedness is Incurred that is equal to or greater
            than the Average Life of the Indebtedness being refinanced;

      (3)   such Refinancing Indebtedness is Incurred in an aggregate principal
            amount (or if issued with original issue discount, an aggregate
            issue price) that is equal to or less than the sum of the aggregate
            principal amount (or if issued with original issue discount, the
            aggregate accreted value) then outstanding of the Indebtedness being
            refinanced (plus, without duplication, any additional Indebtedness
            Incurred to pay interest or premiums required by the instruments
            governing such existing Indebtedness and fees Incurred in connection
            therewith); and

      (4)   if the Indebtedness being refinanced is subordinated in right of
            payment to the Notes, such Refinancing Indebtedness is subordinated
            in right of payment to the Notes on terms at least as favorable to
            the holders as those contained in the documentation governing the
            Indebtedness being extended, refinanced, renewed, replaced, defeased
            or refunded.

      "Related Business Assets" means assets used or useful in the Oil and Gas
Business.

      "Representative" means any trustee, agent or representative (if any) of an
issue of Senior Indebtedness.

      "Restricted Investment" means any Investment other than a Permitted
Investment.


                                       40
<PAGE>
      "Restricted Subsidiary" means the Subsidiary Issuer and any other
Subsidiary of the Parent other than an Unrestricted Subsidiary.

      "S&P" means Standard & Poor's Ratings Group, Inc. or any successor to the
rating agency business thereof.

      "Sale/Leaseback Transaction" means an arrangement relating to property now
owned or hereafter acquired whereby the Parent or a Restricted Subsidiary
transfers such property to a Person and the Parent or a Restricted Subsidiary
leases it from such Person.

      "SEC" means the U.S. Securities and Exchange Commission.

      "Securities Act" means the Securities Act of 1933 and any successor
statute thereto, in each case as amended from time to time.

      "Senior Indebtedness" means, whether outstanding on the Issue Date or
thereafter issued, created, Incurred or assumed, the Bank Indebtedness and all
amounts payable by the Parent or the Subsidiary Issuer, as the case may be,
under or in respect of all other Indebtedness of the Parent or the Subsidiary
Issuer, as the case may be, including premiums and accrued and unpaid interest
(including interest accruing on or after the filing of any petition in
bankruptcy or for reorganization relating to the Parent or the Subsidiary
Issuer, as the case may be, at the rate specified in the documentation with
respect thereto whether or not a claim for post filing interest is allowed in
such proceeding) and fees relating thereto; provided, however, that Senior
Indebtedness will not include:

      (1)   any Indebtedness Incurred in violation of this Indenture;

      (2)   any obligation of the Parent to any Subsidiary;

      (3)   any liability for Federal, state, foreign, local or other taxes owed
            or owing by the Parent or the Subsidiary Issuer;

      (4)   any accounts payable or other liability to trade creditors arising
            in the ordinary course of business (including Guarantees thereof or
            instruments evidencing such liabilities);

      (5)   any Indebtedness, Guarantee or obligation of the Parent or the
            Subsidiary Issuer, as the case may be, that is expressly subordinate
            or junior in right of payment to any other Indebtedness, Guarantee
            or obligation of the Parent or the Subsidiary Issuer, as the case
            may be, including, without limitation, any Senior Subordinated
            Indebtedness and any Subordinated Obligations; or

      (6)   any Capital Stock.

      "Senior Subordinated Indebtedness" means (a) in the case of the Parent,
the Parent Notes and any other Indebtedness of the Parent that specifically
provides that such Indebtedness of the Parent is to rank equally with the Parent
Notes in right of payment and is not subordinated by its terms in right of
payment to any Indebtedness or other obligation of the Parent which is not


                                       41
<PAGE>
Senior Indebtedness of the Parent; or (b) in the case of the Subsidiary Issuer,
the Subsidiary Notes and any other Indebtedness of the Subsidiary Issuer that
specifically provides that such Indebtedness of the Subsidiary Issuer is to rank
equally with the Subsidiary Notes in right of payment and is not subordinated by
its terms in right of payment to any Indebtedness or other obligation of the
Subsidiary Issuer which is not Senior Indebtedness of the Subsidiary Issuer.

      "Significant Subsidiary" means any Restricted Subsidiary that would be a
"Significant Subsidiary" of the Parent within the meaning of Rule 1-02 under
Regulation S-X promulgated by the SEC.

      "Special Record Date" for the payment of any Defaulted Interest means a
date fixed by the Trustee pursuant to Section 1.10(a).

      "Stated Maturity" means, with respect to any security, the date specified
in such security as the fixed date on which the payment of principal of such
security is due and payable, including pursuant to any mandatory redemption
provision, but shall not include any contingent obligations to repay, redeem or
repurchase any such principal prior to the date originally scheduled for the
payment thereof.

      "Subordinated Obligation" means any Indebtedness of the Parent or the
Subsidiary Issuer (whether outstanding on the Issue Date or thereafter Incurred)
which is subordinate or junior in right of payment to the Notes pursuant to a
written agreement.

      "Subsidiary" of any Person means (a) any corporation, association or other
business entity (other than a partnership, joint venture, limited liability
company or similar entity) of which more than 50% of the total ordinary voting
power of shares of Capital Stock entitled (without regard to the occurrence of
any contingency) to vote in the election of directors, managers or trustees
thereof (or persons performing similar functions) or (b) any partnership, joint
venture limited liability company or similar entity of which more than 50% of
the capital accounts, distribution rights, total equity and voting interests or
general or limited partnership interests, as applicable, is, in the case of
clauses (a) and (b), at the time owned or controlled, directly or indirectly, by
(1) such Person, (2) such Person and one or more Subsidiaries of such Person or
(3) one or more Subsidiaries of such Person. Unless otherwise specified herein,
each reference to a Subsidiary will refer to a Subsidiary of the Parent.

      "Subsidiary Guarantee" means, individually, any unconditional Guarantee,
on a senior subordinated basis, of payment of the Parent Notes and the
Subsidiary Notes by a Subsidiary Guarantor pursuant to the terms of this
Indenture and any supplemental indenture thereto, and, collectively, all such
Guarantees. Each such Subsidiary Guarantee will be in the form prescribed by
this Indenture.

      "Subsidiary Guarantor" means any Restricted Subsidiary that has provided a
Subsidiary Guarantee in accordance with Section 1004(b)(4) or Section 1013.

      "Trust Indenture Act" means the Trust Indenture Act of 1939 as in force at
the date as of which this instrument was executed; provided, however, that in
the event the Trust Indenture Act of 1939 is amended after such date, "Trust
Indenture Act" means, to the extent required by any such amendment, the Trust
Indenture Act of 1939 as so amended.


                                       42
<PAGE>
      "Trustee" means the Person named as the "Trustee" in the first paragraph
of this Indenture until a successor Trustee shall have become such pursuant to
the applicable provisions of this Indenture, and thereafter "Trustee" shall mean
or include each Person who is then a Trustee hereunder.

      "Uniform Commercial Code" means the Uniform Commercial Code of the State
of New York, as amended.

      "Unrestricted Subsidiary" means:

      (1)   any Subsidiary of the Parent that at the time of determination shall
            be designated an Unrestricted Subsidiary by the Board of Directors
            of the Parent in the manner provided below; and

      (2)   any Subsidiary of an Unrestricted Subsidiary.

      The Board of Directors of the Parent may designate any Subsidiary of the
Parent (including any newly acquired or newly formed Subsidiary or a Person
becoming a Subsidiary through merger or consolidation or Investment therein) to
be an Unrestricted Subsidiary only if:

      (1)   such Subsidiary or any of its Subsidiaries does not own any Capital
            Stock or Indebtedness of or have any Investment in, or own or hold
            any Lien on any property of, any other Subsidiary of the Parent
            which is not a Subsidiary of the Subsidiary to be so designated or
            otherwise an Unrestricted Subsidiary;

      (2)   all the Indebtedness of such Subsidiary and its Subsidiaries shall,
            at the date of designation, and will at all times thereafter,
            consist of Non-Recourse Debt;

      (3)   such designation and the Investment of the Parent in such Subsidiary
            complies with Section 1005;

      (4)   such Subsidiary, either alone or in the aggregate with all other
            Unrestricted Subsidiaries, does not operate, directly or indirectly,
            all or substantially all of the business of the Parent and its
            Subsidiaries;

      (5)   such Subsidiary is a Person with respect to which neither the Parent
            nor any of its Restricted Subsidiaries has any direct or indirect
            obligation:

            (a)   to subscribe for additional Capital Stock of such Person; or

            (b)   to maintain or preserve such Person's financial condition or
                  to cause such Person to achieve any specified levels of
                  operating results; and

      (6)   on the date such Subsidiary is designated an Unrestricted
            Subsidiary, such Subsidiary is not a party to any agreement,
            contract, arrangement or understanding with the Parent or any
            Restricted Subsidiary with terms substantially less favorable to the
            Parent than those that might have been obtained from Persons who are
            not Affiliates of the Parent.


                                       43
<PAGE>
         Any such designation by the Board of Directors of the Parent shall be
evidenced to the Trustee by filing with the Trustee a resolution of the Board of
Directors of the Parent giving effect to such designation and an Officers'
Certificate certifying that such designation complies with the foregoing
conditions. If, at any time, any Unrestricted Subsidiary would fail to meet the
foregoing requirements as an Unrestricted Subsidiary, it shall thereafter cease
to be an Unrestricted Subsidiary for purposes of this Indenture and any
Indebtedness of such Subsidiary shall be deemed to be Incurred as of such date.

         The Board of Directors of the Parent may designate any Unrestricted
Subsidiary to be a Restricted Subsidiary; provided that immediately after giving
effect to such designation, no Default or Event of Default shall have occurred
and be continuing or would occur as a consequence thereof and the Parent could
Incur at least $1.00 of additional Indebtedness under Section 1004(a) on a pro
forma basis taking into account such designation.

         "Vice President", when used with respect to the Parent, the Subsidiary
Issuer or the Trustee, means any vice president, whether or not designated by a
number or a word or words added before or after the title "vice president".

         "U.S. Dollar Equivalent" means, with respect to any monetary amount in
a currency other than the U.S. dollar, at or as of any time for the
determination thereof, the amount of U.S. dollars obtained by converting such
foreign currency involved in such computation into U.S. dollars at the spot rate
for the purchase of U.S. dollars with the applicable foreign currency as quoted
by Reuters (or, if Reuters ceases to provide such spot quotations, by any other
reputable service as is providing such spot quotations, as selected by the
Parent or the Subsidiary Issuer) at approximately 11:00 a.m. (New York City
time) on the date not more than two Business Days prior to such determination.

         "U.S. Government Obligations" means securities that are (a) direct
obligations of the United States of America for the timely payment of which its
full faith and credit is pledged or (b) obligations of a Person controlled or
supervised by and acting as an agency or instrumentality of the United States of
America the timely payment of which is unconditionally guaranteed as a full
faith and credit obligation of the United States of America, which, in either
case, are not callable or redeemable at the option of the issuer thereof, and
shall also include a depositary receipt issued by a bank (as defined in Section
3(a)(2) of the Securities Act), as custodian with respect to any such U.S.
Government Obligations or a specific payment of principal of or interest on any
such U.S. Government Obligations held by such custodian for the account of the
holder of such depositary receipt; provided that (except as required by law)
such custodian is not authorized to make any deduction from the amount payable
to the holder of such depositary receipt from any amount received by the
custodian in respect of the U.S. Government Obligations or the specific payment
of principal of or interest on the U.S. Government Obligations evidenced by such
depositary receipt.

         "Voting Stock" of a corporation means all classes of Capital Stock of
such corporation then outstanding and normally entitled to vote in the election
of directors.


                                       44
<PAGE>
         "Wholly-Owned Subsidiary" means a Restricted Subsidiary of the Parent,
all of the Capital Stock of which (other than directors' qualifying shares) is
owned by the Parent or another Wholly-Owned Subsidiary."

         (B) Section 101 of each of the Original Indentures is hereby amended by
addition of the following provisions at the end of the subsection captioned
"Rules of Construction":

                  "(6)     references to sections of or rules under the Exchange
                           Act or the Securities Act shall be deemed to include
                           substitute, replacement of successor sections or
                           rules adopted by the SEC from time to time;

                  (7)      references to "$", "$" or "U.S. dollars" shall refer
                           to the lawful currency of the United States of
                           America;

                  (8)      whenever the definitions in this Article I or the
                           provisions in Articles III or VI of this Indenture
                           refer to an amount in U.S. dollars, that amount shall
                           be deemed to refer to the U.S. Dollar Equivalent of
                           the amount of any obligation denominated in any other
                           currency or currencies, including composite
                           currencies; and

                  (9)      section references (other than to statutes in decimal
                           format (e.g., Section 1.1) shall refer to sections in
                           this First Supplemental Indenture; and section
                           references (other than to statutes) in non-decimal
                           format (e.g., Section 101) shall refer to sections in
                           the Original Indentures or the Indenture."

         SECTION 2.3. COVENANTS

         Article Ten of each of the Original Indentures is hereby supplemented,
amended and restated to read in its entirety as follows:

                                  "Article Ten

                                    Covenants

                  Section 1001  Payment of Principal, Premium and Interest

                  The Parent covenants and agrees for the benefit of the Holders
         of the Parent Notes, as Holders of Units, that it shall promptly pay
         the principal of and interest on the Parent Notes on the dates and in
         the manner provided in the Parent Notes and in this Indenture.
         Principal and interest on the Parent Notes shall be considered paid on
         the date due if on such date the Trustee or Paying Agent holds in
         accordance with this Indenture money sufficient to pay all principal
         and interest then due and the Trustee or Paying Agent, as the case may
         be, is not prohibited from paying money to Holders of the Parent Notes
         on that date pursuant to the terms of this Indenture. The Parent shall
         pay interest on overdue principal at the rate specified therefor in the
         Parent Notes, and it shall pay interest on overdue installments of
         interest at the same rate to the extent lawful.


                                       45
<PAGE>
                  The Subsidiary Issuer covenants and agrees for the benefit of
         the Holders of the Subsidiary Notes, as Holders of Units, that it shall
         promptly pay the principal of and interest on the Subsidiary Notes
         (including Additional Amounts, if any) on the dates and in the manner
         provided in the Subsidiary Notes and in this Indenture. Principal and
         interest on the Subsidiary Notes (including Additional Amounts, if any)
         shall be considered paid on the date due if on such date the Trustee or
         Paying Agent holds in accordance with this Indenture money sufficient
         to pay all principal and interest then due (including Additional
         Amounts, if any) and the Trustee or Paying Agent, as the case may be,
         is not prohibited from paying money to Holders of the Subsidiary Notes
         on that date pursuant to the terms of this Indenture. The Subsidiary
         Issuer shall pay interest on overdue principal at the rate specified
         therefor in the Parent Notes, and it shall pay interest on overdue
         installments of interest at the same rate to the extent lawful.

                  Section 1002  Maintenance of Office or Agency

                  The Parent and the Subsidiary Issuer shall maintain in the
         Borough of Manhattan, The City of New York, New York an office or
         agency (which may be an office of the Trustee or an affiliate of the
         Trustee, Registrar or co-registrar) where Notes or Units may be
         surrendered for registration of transfer or for exchange and where
         notices and demands to or upon the Parent or the Subsidiary Issuer in
         respect of the Notes or Units and this Indenture may be served. The
         Parent and the Subsidiary Issuer shall give prompt written notice to
         the Trustee of the location, and any change in the location, of such
         office or agency. If at any time the Parent and the Subsidiary Issuer
         shall fail to maintain any such required office or agency or shall fail
         to furnish the Trustee with the address thereof, such presentations,
         surrenders, notices and demands may be made or served at the Corporate
         Trust Office of the Trustee.

                  The Parent and the Subsidiary Issuer may also from time to
         time designate one or more other offices or agencies where the Notes or
         the Units may be presented or surrendered for any or all such purposes
         and may from time to time rescind such designations; provided, however,
         that no such designation or rescission shall in any manner relieve the
         Parent and the Subsidiary Issuer of its obligation to maintain an
         office or agency in the Borough of Manhattan, The City of New York, New
         York for such purposes. The Parent and the Subsidiary Issuer shall give
         prompt written notice to the Trustee of any such designation or
         rescission and of any change in the location of any such other office
         or agency.

                  The Parent and the Subsidiary Issuer hereby designate the
         Corporate Trust Office of the Trustee as one such office or agency in
         accordance with Section 1.3.

                  Section 1003  Additional Amounts

                  All payments made by the Subsidiary Issuer in respect of the
         Subsidiary Notes or the Parent under the Parent Guarantee will be made
         without withholding or deduction for or on account of any present or
         future taxes, duties, assessments,

                                       46
<PAGE>
         or other governmental charges of any nature imposed or levied by or on
         behalf of Canada or any political subdivision or authority thereof or
         therein having power to tax, unless the Subsidiary Issuer or the Parent
         under the Parent Guarantee is required by law or by the interpretation
         of administration thereof by the relevant government authority or
         agency to withhold or deduct such taxes, duties, assessments, or other
         governmental charges. The Subsidiary Issuer or the Parent under the
         Parent Guarantee, as the case may be, will make the required
         withholding or deduction, make payment of the amount so withheld or
         deducted to the appropriate government authority and pay any additional
         amounts that may be necessary to ensure that the net amounts received
         by the Holders after the withholding or deduction (including any
         withholding or deduction for such additional amounts) equals the
         respective amounts of principal and interest which would have been
         receivable in respect of the Subsidiary Notes in the absence of the
         withholding or deduction ("Additional Amounts"). No additional amounts
         shall, however, be payable:

                  (a) to a Holder who is subject to the taxes, duties,
         assessments or other governmental charges by reason of any present or
         former connection between the Holder and Canada other than solely by
         the holding of the Subsidiary Notes or by the receipt of payments in
         respect of the Subsidiary Notes;

                  (b) if the payment would not have been subject to the taxes,
         duties, assessments or other governmental charges had the request for
         payment been made within 30 days of the related due date or, in case
         the full amount of funds payable had not been provided to the principal
         paying agent when due, within 30 days of the date on which the funds
         were received by the principal paying agent and notice of the
         availability of the funds has been given;

                  (c) to the extent that the taxes, duties, assessments or other
         governmental charges would not have been imposed but for the failure of
         the Holder to comply with any certification, identification or other
         reporting requirements concerning the nationality, residence, identity
         or connection with Canada of the Holder if:

                           (1)      such compliance is required or imposed by
                                    law as a precondition to exemption from all
                                    or a part of the tax, duty, assessment or
                                    other governmental charge; and

                           (2)      at least 30 days prior to the first interest
                                    payment date with respect to which this
                                    clause (c) will apply, the Parent or the
                                    Subsidiary Issuer has notified the Holders
                                    that they will be required to comply with
                                    this requirement; or

                  (d) to a Holder that does not deal at arm's length (as
         contemplated by the Income Tax Act (Canada)) with the Subsidiary
         Issuer.

                  No Additional Amounts will be paid to a Holder that is a
         depositary or its nominee, a fiduciary or a partnership or other than
         the sole beneficial owner of the

                                       47
<PAGE>
         payment to the extent that a beneficiary or settlor with respect to the
         fiduciary or a member of the partnership or beneficial owner would not
         have been entitled to receive payment of the Additional Amounts had the
         beneficiary, settlor, member or beneficial owner been the Holder of the
         Subsidiary Note.

                  Section 1004  Limitation on Indebtedness

                  (e) The Parent will not, and will not permit any of its
         Restricted Subsidiaries to, Incur any Indebtedness (including Acquired
         Indebtedness); provided, however, that the Parent and any Subsidiary
         Guarantor may Incur Indebtedness if on the date thereof:

                           (1)      the Consolidated Coverage Ratio for the
                                    Parent and its Restricted Subsidiaries is at
                                    least 2.50 to 1.00; and

                           (2)      no Default or Event of Default will have
                                    occurred or be continuing or would occur as
                                    a consequence of Incurring the Indebtedness
                                    or transactions relating to such Incurrence.

                  (f) Notwithstanding Section 1004(a), Indebtedness may be
         Incurred as follows:

                           (1)      Indebtedness of the Parent and its
                                    Restricted Subsidiaries Incurred pursuant to
                                    the Credit Facilities, so long as the
                                    aggregate amount of all Indebtedness
                                    Incurred under this clause (1) that is at
                                    any time, outstanding does not exceed the
                                    greater of (x) $360 million and (y) $100
                                    million plus 20% of ACNTA, in each case, as
                                    of the date of such Incurrence;

                           (2)      Indebtedness of the Parent owing to and held
                                    by any Restricted Subsidiary or Indebtedness
                                    of a Restricted Subsidiary owing to and held
                                    by the Parent or any Restricted Subsidiary;
                                    provided, however,

                                    (a)     if the Parent is the obligor on such
                                            Indebtedness, such Indebtedness is
                                            expressly subordinated to the prior
                                            payment in full in cash of all
                                            obligations with respect to the
                                            Notes comprising the Units; and

                                    (b)     (i) any subsequent issuance or
                                            transfer of Capital Stock or any
                                            other event which results in any
                                            such Indebtedness being beneficially
                                            held by a Person other than the
                                            Parent or a Restricted Subsidiary of
                                            the Parent; and (ii) any sale or
                                            other transfer of any such
                                            Indebtedness to a Person other than
                                            the Parent or a Restricted
                                            Subsidiary of the Parent


                                       48
<PAGE>
                                    shall be deemed, in each case, to constitute
                                    an Incurrence of such Indebtedness by the
                                    Parent or such Subsidiary, as the case may
                                    be;

                           (3)      Indebtedness represented by (a) the Notes
                                    and the Parent Guarantee issued on the Issue
                                    Date, (b) any Indebtedness (other than the
                                    Indebtedness described in Section
                                    1004(b)(1), Section 1004(b)(2) and Section
                                    1004(b)(5)) outstanding on the Issue Date
                                    and (c) any Refinancing Indebtedness
                                    Incurred in respect of any Indebtedness
                                    described in this Section 1004(b)(3) or
                                    Section 1004(b)(4) or Incurred pursuant to
                                    Section 1004(a);

                           (4)      Indebtedness of a Restricted Subsidiary
                                    Incurred and outstanding on the date on
                                    which such Restricted Subsidiary was
                                    acquired by the Parent (other than
                                    Indebtedness Incurred (a) to provide all or
                                    any portion of the funds utilized to
                                    consummate the transaction or series of
                                    related transactions pursuant to which such
                                    Restricted Subsidiary became a Restricted
                                    Subsidiary or was otherwise acquired by the
                                    Parent or (b) otherwise in connection with,
                                    or in contemplation of, such acquisition);
                                    provided, however, that at the time such
                                    Restricted Subsidiary is acquired by the
                                    Parent (i) the Parent would have been able
                                    to Incur $1.00 of additional Indebtedness
                                    pursuant to the first paragraph of this
                                    covenant after giving effect to the
                                    Incurrence of such Indebtedness pursuant to
                                    this clause (4) and (ii) such Restricted
                                    Subsidiary (unless it is a Foreign
                                    Subsidiary) shall execute and deliver a
                                    supplemental indenture to this Indenture
                                    providing for a Subsidiary Guarantee of such
                                    Subsidiary Issuer; and

                           (5)      in addition to the items referred to in
                                    clauses (1) through (4) above, Indebtedness
                                    of the Parent and its Restricted
                                    Subsidiaries (including Indebtedness of a
                                    Restricted Subsidiary Incurred and
                                    outstanding on the date such Restricted
                                    Subsidiary was acquired by the Parent) in an
                                    aggregate outstanding principal amount
                                    which, when taken together with the
                                    principal amount of all other Indebtedness
                                    Incurred pursuant to this clause (5) and
                                    then outstanding, will not exceed $50
                                    million at any time outstanding.

                  (g) The Parent will not Incur any Indebtedness pursuant to
         Section 1004(b) if the proceeds thereof are used, directly or
         indirectly, to refinance any Subordinated Obligations of the Parent
         unless such Indebtedness will be subordinated to the Notes to at least
         the same extent as such Subordinated

                                       49
<PAGE>
         Obligations. No Restricted Subsidiary may Incur any Indebtedness if the
         proceeds are used to refinance Indebtedness of the Parent.

                  (h) For purposes of determining the outstanding principal
         amount of any particular Indebtedness Incurred pursuant to this Section
         1004:

                           (1)      in the event that Indebtedness meets the
                                    criteria of more than one of the types of
                                    Indebtedness described in Section 1004(a)
                                    and Section 1004(b), the Parent, in its sole
                                    discretion, will classify such item of
                                    Indebtedness on the date of Incurrence, and
                                    thereafter may reclassify such item of
                                    Indebtedness, and only be required to
                                    include the amount and type of such
                                    Indebtedness in one of such clauses;

                           (2)      all Indebtedness outstanding on the date of
                                    this Indenture under the Credit Facilities
                                    shall be deemed initially Incurred on the
                                    Issue Date under Section 1004(b)(1) and not
                                    Section 1004(a) or Section 1004(b);

                           (3)      Guarantees of, or obligations in respect of
                                    letters of credit relating to, Indebtedness
                                    which is otherwise included in the
                                    determination of a particular amount of
                                    Indebtedness shall not be included;

                           (4)      if obligations in respect of letters of
                                    credit are Incurred pursuant to the Credit
                                    Facility and are being treated as Incurred
                                    pursuant to Section 1004(b)(1) and the
                                    letters of credit relate to other
                                    Indebtedness, then such other Indebtedness
                                    shall not be included;

                           (5)      the principal amount of any Disqualified
                                    Stock of the Parent or a Restricted
                                    Subsidiary will be equal to the greater of
                                    the maximum mandatory redemption or
                                    repurchase price (not including, in either
                                    case, any redemption or repurchase premium)
                                    or the liquidation preference thereof;

                           (6)      Indebtedness permitted by this Section 1004
                                    need not be permitted solely by reference to
                                    one provision permitting such Indebtedness
                                    but may be permitted in part by one such
                                    provision and in part by one or more other
                                    provisions of this covenant permitting such
                                    Indebtedness; and

                           (7)      the amount of Indebtedness issued at a price
                                    that is less than the principal amount
                                    thereof will be equal to the amount of the
                                    liability in respect thereof determined in
                                    accordance with GAAP.


                                       50
<PAGE>
                  (i) Accrual of interest, accrual of dividends, the accretion
         of accreted value, the payment of interest in the form of additional
         Indebtedness and the payment of dividends in the form of additional
         shares of Preferred Stock or Disqualified Stock will not be deemed to
         be an Incurrence of Indebtedness for purposes of this Section 1004. The
         amount of any Indebtedness outstanding as of any date shall be (i) the
         accreted value thereof in the case of any Indebtedness issued with
         original issue discount and (ii) the principal amount or liquidation
         preference thereof, together with any interest thereon that is more
         than 30 days past due, in the case of any other Indebtedness.

                  (j) In addition, the Parent will not permit any of its
         Unrestricted Subsidiaries to Incur any Indebtedness or issue any shares
         of Disqualified Stock, other than Non-Recourse Debt. If at any time an
         Unrestricted Subsidiary becomes a Restricted Subsidiary, the Parent
         will require such Subsidiary to provide a Subsidiary Guarantee, and any
         Indebtedness of such Subsidiary shall be deemed to be Incurred by a
         Restricted Subsidiary of the Parent as of such date (and, if such
         Indebtedness is not permitted to be Incurred as of such date under this
         Section 1004, the Parent shall be in Default of this covenant).

                  (k) For purposes of determining compliance with any U.S.
         dollar-denominated restriction on the Incurrence of Indebtedness, the
         U.S. Dollar Equivalent principal amount of Indebtedness denominated in
         a foreign currency shall be calculated based on the relevant currency
         exchange rate in effect on the date such Indebtedness was Incurred, in
         the case of term Indebtedness, or first committed, in the case of
         revolving credit Indebtedness; provided that if such Indebtedness is
         Incurred to refinance other Indebtedness denominated in a foreign
         currency, and such refinancing would cause the applicable U.S.
         dollar-dominated restriction to be exceeded if calculated at the
         relevant currency exchange rate in effect on the date of such
         refinancing, such U.S. dollar-dominated restriction shall be deemed not
         to have been exceeded so long as the principal amount of such
         refinancing Indebtedness does not exceed the principal amount of such
         Indebtedness being refinanced. Notwithstanding any other provision of
         this Section 1004, the maximum amount of Indebtedness that the Parent
         may Incur pursuant to this covenant shall not be deemed to be exceeded
         solely as a result of fluctuations in the exchange rate of currencies.
         The principal amount of any Indebtedness Incurred to refinance other
         Indebtedness, if Incurred in a different currency from the Indebtedness
         being refinanced, shall be calculated based on the currency exchange
         rate applicable to the currencies in which such Refinancing
         Indebtedness is denominated that is in effect on the date of such
         refinancing.

                  Section 1005  Limitation on Restricted Payments

                  (l) The Parent will not, and will not permit any of its
         Restricted Subsidiaries, directly or indirectly, to: (1) declare or pay
         any dividend or make any distribution on or in respect of its Capital
         Stock (including any payment in connection with any merger or
         consolidation involving the Parent or any of its Restricted
         Subsidiaries) except: (A) dividends or distributions payable in Capital

                                       51
<PAGE>
         Stock of the Parent (other than Disqualified Stock) or in options,
         warrants or other rights to purchase such Capital Stock of the Parent;
         and (B) dividends or distributions payable to the Parent or a
         Restricted Subsidiary of the Parent (and if such Restricted Subsidiary
         is not a Wholly Owned Subsidiary, to its other holders of common
         Capital Stock on a pro rata basis); (2) purchase, redeem, retire or
         otherwise acquire for value any Capital Stock of the Parent or any
         direct or indirect parent of the Parent held by Persons other than the
         Parent or a Restricted Subsidiary of the Parent (other than in exchange
         for Capital Stock of the Parent (other than Disqualified Stock)); (3)
         purchase, repurchase, redeem, defease or otherwise acquire or retire
         for value, prior to scheduled maturity, scheduled repayment or
         scheduled sinking fund payment, any Subordinated Obligations of the
         Parent or the Subsidiary Issuer (other than the purchase, repurchase,
         redemption, defeasance or other acquisition or retirement of
         Subordinated Obligations purchased in anticipation of satisfying a
         sinking fund obligation, principal installment or final maturity, in
         each case due within one year of the date of purchase, repurchase,
         redemption, defeasance or other acquisition or retirement); or (4) make
         any Restricted Investment in any Person; (any such dividend,
         distribution, purchase, redemption, repurchase, defeasance, other
         acquisition, retirement or Restricted Investment referred to in clauses
         (1) through (4) of this Section 1005(a) shall be referred to herein as
         a "Restricted Payment"), if at the time the Parent or such Restricted
         Subsidiary makes such Restricted Payment:

                           (A)      a Default shall have occurred and be
                                    continuing (or would result therefrom); or

                           (B)      the Parent is not able to Incur an
                                    additional $1.00 of Indebtedness pursuant to
                                    Section 1004(a) after giving effect, on a
                                    pro forma basis, to such Restricted Payment;
                                    or

                           (C)      the aggregate amount of such Restricted
                                    Payment and all other Restricted Payments
                                    declared or made subsequent to the Issue
                                    Date would exceed the sum of:

                                    (i)     50% of Consolidated Net Income for
                                            the period (treated as one
                                            accounting period) from the
                                            beginning of the first fiscal
                                            quarter commencing after the date of
                                            this Indenture to the end of the
                                            most recent fiscal quarter ending
                                            prior to the date of such Restricted
                                            Payment for which financial
                                            statements are in existence (or, in
                                            case such Consolidated Net Income is
                                            a deficit, minus 100% of such
                                            deficit); plus

                                    (ii)    100% of the aggregate Net Cash
                                            Proceeds received by the Parent from
                                            the issue or sale of its Capital
                                            Stock (other than Disqualified
                                            Stock) or other

                                       52
<PAGE>
                                            capital contributions subsequent to
                                            the Issue Date (other than Net Cash
                                            Proceeds received from an issuance
                                            or sale of such Capital Stock to a
                                            Subsidiary of the Parent or an
                                            employee stock ownership plan,
                                            option plan or similar trust to the
                                            extent such sale to an employee
                                            stock ownership plan or similar
                                            trust is financed by loans from or
                                            Guaranteed by the Parent or any
                                            Restricted Subsidiary unless such
                                            loans have been repaid with cash on
                                            or prior to the date of
                                            determination); plus

                                    (iii)   the amount by which Indebtedness of
                                            the Parent or its Restricted
                                            Subsidiaries is reduced on the
                                            Parent's balance sheet upon the
                                            conversion or exchange (other than
                                            by a Subsidiary of the Parent)
                                            subsequent to the Issue Date of any
                                            Indebtedness of the Parent or its
                                            Restricted Subsidiaries convertible
                                            or exchangeable for Capital Stock
                                            (other than Disqualified Stock) of
                                            the Parent (less the amount of any
                                            cash, or the fair market value of
                                            any other property, distributed by
                                            the Parent upon such conversion or
                                            exchange); plus

                                    (iv)    the amount equal to the net
                                            reduction in Restricted Investments
                                            made by the Parent or any of its
                                            Restricted Subsidiaries in any
                                            Person resulting from: (A)
                                            repurchases or redemptions of such
                                            Restricted Investments by such
                                            Person, proceeds realized upon the
                                            sale of such Restricted Investment
                                            to an unaffiliated purchaser,
                                            repayments of loans or advances or
                                            other transfers of assets (including
                                            by way of dividend or distribution)
                                            by such Person to the Parent or any
                                            Restricted Subsidiary of the Parent;
                                            or (B) the redesignation of
                                            Unrestricted Subsidiaries as
                                            Restricted Subsidiaries (valued in
                                            each case as provided in the
                                            definition of "Investment") not to
                                            exceed, in the case of any
                                            Unrestricted Subsidiary, the amount
                                            of Investments previously made by
                                            the Parent or any Restricted
                                            Subsidiary in such Unrestricted
                                            Subsidiary, which amount in each
                                            case under this clause (iv) was
                                            included in the calculation of the
                                            amount of Restricted Payments;
                                            provided, however, that no amount
                                            will be included under this clause
                                            (iv) to the extent it is already
                                            included in Consolidated Net Income.


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<PAGE>
                  (m) The foregoing provisions of Section 1005(a) will not
         prohibit:

                           (1)      any purchase, repurchase, redemption,
                                    defeasance or other acquisition or
                                    retirement of Capital Stock, Disqualified
                                    Stock or Subordinated Obligations of the
                                    Parent or the Subsidiary Issuer made by
                                    exchange for, or out of the proceeds of the
                                    substantially concurrent sale of, Capital
                                    Stock of the Parent (other than Disqualified
                                    Stock and other than Capital Stock issued or
                                    sold to a Subsidiary or an employee stock
                                    ownership plan or similar trust to the
                                    extent such sale to an employee stock
                                    ownership plan or similar trust is financed
                                    by loans from or Guaranteed by the Parent or
                                    any Restricted Subsidiary unless such loans
                                    have been repaid with cash on or prior to
                                    the date of determination); provided,
                                    however, that (a) such purchase, repurchase,
                                    redemption, defeasance, acquisition or
                                    retirement will be excluded in subsequent
                                    calculations of the amount of Restricted
                                    Payments and (b) the Net Cash Proceeds from
                                    such sale of Capital Stock will be excluded
                                    from clause (c)(ii) of the preceding
                                    paragraph; and provided, further, that for
                                    purposes of this clause (1), any sale made
                                    within 30 days of such purchase, repurchase,
                                    redemption, defeasance or other acquisition
                                    or retirement, shall be deemed to be a
                                    "substantially current sale";

                           (2)      any purchase, repurchase, redemption,
                                    defeasance or other acquisition or
                                    retirement of Subordinated Obligations of
                                    the Parent or the Subsidiary Issuer made by
                                    exchange for, or out of the proceeds of the
                                    substantially concurrent sale of,
                                    Subordinated Obligations of the Parent or
                                    the Subsidiary Issuer that, in each case, is
                                    permitted to be Incurred pursuant to Section
                                    1004 and that in each case constitutes
                                    Refinancing Indebtedness; provided, however,
                                    that such purchase, repurchase, redemption,
                                    defeasance, acquisition or retirement will
                                    be excluded in subsequent calculations of
                                    the amount of Restricted Payments;

                           (3)      any purchase, repurchase, redemption,
                                    defeasance or other acquisition or
                                    retirement of Disqualified Stock of the
                                    Parent or a Restricted Subsidiary made by
                                    exchange for or out of the proceeds of the
                                    substantially concurrent sale of
                                    Disqualified Stock of the Parent or such
                                    Restricted Subsidiary, as the case may be,
                                    that, in each case, is permitted to be
                                    Incurred pursuant to Section 1004 and that
                                    in each case constitutes Refinancing
                                    Indebtedness; provided, however, that such
                                    purchase, repurchase, redemption,
                                    defeasance, acquisition or retirement will
                                    be

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<PAGE>
                                    excluded in subsequent calculations of the
                                    amount of Restricted Payments;

                           (4)      so long as no Default or Event of Default
                                    has occurred and is continuing, any purchase
                                    or redemption of Subordinated Obligations
                                    from Net Available Cash to the extent
                                    permitted under Section 1009; provided,
                                    however, that such purchase or redemption
                                    will be excluded in subsequent calculations
                                    of the amount of Restricted Payments;

                           (5)      dividends paid within 60 days after the date
                                    of declaration if at such date of
                                    declaration such dividend would have
                                    complied with this provision; provided,
                                    however, that such dividends will be
                                    included in subsequent calculations of the
                                    amount of Restricted Payments;

                           (6)      so long as no Default or Event of Default
                                    has occurred and is continuing,

                                    (1)     the purchase, redemption or other
                                            acquisition, cancellation or
                                            retirement for value of Capital
                                            Stock, or options, warrants, equity
                                            appreciation rights or other rights
                                            to purchase or acquire Capital Stock
                                            of the Parent or any Restricted
                                            Subsidiary of the Parent or any
                                            parent of the Parent held by any
                                            existing or former employees or
                                            management of the Parent or any
                                            Subsidiary of the Parent or their
                                            assigns, estates or heirs, in each
                                            case in connection with the
                                            repurchase provisions under employee
                                            stock option or stock purchase
                                            agreements or other agreements to
                                            compensate management employees;
                                            provided that such redemptions or
                                            repurchases pursuant to this clause
                                            will not exceed $2 million in the
                                            aggregate during any calendar year
                                            (with 50% of the unused amounts in
                                            any calendar year being carried over
                                            to succeeding calendar years);
                                            provided, further, however, that
                                            such amount in any calendar year may
                                            be increased by an amount not to
                                            exceed (A) the cash proceeds
                                            received by the Parent from the sale
                                            of Capital Stock of the Parent to
                                            members of management or directors
                                            of the Parent and its Restricted
                                            Subsidiaries that occurs after the
                                            Issue Date (to the extent the cash
                                            proceeds from the sale of such
                                            Equity Interests have not otherwise
                                            been applied to the payment of
                                            Restricted Payments by virtue of the
                                            preceding paragraph (c)), plus (B)
                                            up to $2 million of any cash
                                            proceeds of key man

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<PAGE>
                                            life insurance policies received by
                                            the Parent and its Restricted
                                            Subsidiaries after the Issue Date,
                                            less (C) the amount of any
                                            Restricted Payments made pursuant to
                                            clauses (A) and (B) of this clause
                                            (6)(a); provided, further, however,
                                            that the amount of any such
                                            repurchase or redemption will be
                                            included in subsequent calculations
                                            of the amount of Restricted
                                            Payments; and

                                    (2)     loans or advances to employees of
                                            the Parent or employees or directors
                                            of any Subsidiary of the Parent, in
                                            each case as permitted by the
                                            Section 402 of the Sarbanes-Oxley
                                            Act of 2002, the proceeds of which
                                            are used to purchase Capital Stock
                                            of the Parent, in an aggregate
                                            amount not in excess of $2 million
                                            at any one time outstanding;
                                            provided, however, that the amount
                                            of such loans and advances will be
                                            included in subsequent calculations
                                            of the amount of Restricted
                                            Payments;

                           (7)      so long as no Default or Event of Default
                                    has occurred and is continuing, the
                                    declaration and payment of dividends to
                                    holders of any class or series of
                                    Disqualified Stock of the Parent issued in
                                    accordance with the terms of this Indenture
                                    to the extent such dividends are included in
                                    the definition of "Consolidated Interest
                                    Expense"; provided that the payment of such
                                    dividends will be excluded from subsequent
                                    calculations of the amount of Restricted
                                    Payments;

                           (8)      repurchases of Capital Stock deemed to occur
                                    upon the exercise of stock options, warrants
                                    or other convertible securities if such
                                    Capital Stock represents a portion of the
                                    exercise price thereof; provided, however,
                                    that such repurchases will be excluded from
                                    subsequent calculations of the amount of
                                    Restricted Payments;

                           (9)      the payment of reasonable and customary
                                    directors' fees to the members of the Board
                                    of Directors of the Parent; provided that
                                    such fees are consistent with past practice
                                    or current requirements;

                           (10)     the purchase by the Parent of fractional
                                    shares arising out of stock dividends,
                                    splits or combinations or business
                                    combinations; and


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<PAGE>
                           (11)     Restricted Payments in an amount not to
                                    exceed $25 million; provided that the amount
                                    of such Restricted Payments will be included
                                    in subsequent calculations of the amount of
                                    Restricted Payments.

                  (n) The amount of all Restricted Payments (other than cash)
         shall be the fair market value on the date of such Restricted Payment
         of the asset(s) or securities proposed to be paid, transferred or
         issued by the Parent or such Restricted Subsidiary, as the case may be,
         pursuant to such Restricted Payment. The fair market value of any cash
         Restricted Payment shall be its face amount and any non cash Restricted
         Payment shall be determined conclusively by the Board of Directors of
         the Parent acting in good faith whose resolution with respect thereto
         shall be delivered to the Trustee, such determination to be based upon
         an opinion or appraisal issued by an accounting, appraisal or
         investment banking firm of national standing if such fair market value
         is estimated in good faith by the Board of Directors of the Parent to
         exceed $25 million. Not later than the date of making any Restricted
         Payment, the Parent shall deliver to the Trustee an Officers'
         Certificate stating that such Restricted Payment is permitted and
         setting forth the basis upon which the calculations required by this
         Section 1005 were computed, together with a copy of any fairness
         opinion or appraisal required by this Indenture.

                  Section 1006  Limitation on Layering

                  The Parent will not Incur any Indebtedness if such
         Indebtedness is subordinate or junior in ranking in any respect to any
         Senior Indebtedness of the Parent unless such Indebtedness is Senior
         Subordinated Indebtedness of the Parent or is contractually
         subordinated in right of payment to Senior Subordinated Indebtedness of
         the Parent. Unsecured Indebtedness of the Parent is not deemed to be
         subordinate or junior to secured Indebtedness of the Parent merely
         because it is unsecured.

                  The Subsidiary Issuer will not Incur any Indebtedness if such
         Indebtedness is subordinate or junior in ranking in any respect to any
         Senior Indebtedness of the Subsidiary Issuer unless such Indebtedness
         is Senior Subordinated Indebtedness of the Subsidiary Issuer or is
         contractually subordinated in right of payment to Senior Subordinated
         Indebtedness of the Subsidiary Issuer. Unsecured Indebtedness of the
         Subsidiary Issuer is not deemed to be subordinate or junior to secured
         Indebtedness of the Subsidiary Issuer merely because it is unsecured.

                  Section 1007  Limitation on Liens

                  The Parent will not, and will not permit any of its Restricted
         Subsidiaries to, directly or indirectly, create, Incur or suffer to
         exist any Lien (other than Permitted Liens) upon any of its property or
         assets (including Capital Stock of Restricted Subsidiaries of the
         Parent), whether owned on the date of this

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<PAGE>
         Indenture or acquired after that date, which Lien is securing any
         Senior Subordinated Indebtedness of the Parent or any Restricted
         Subsidiary or Subordinated Obligations of the Parent or any Restricted
         Subsidiary, unless contemporaneously with the Incurrence of such Liens
         effective provision is made to secure the Indebtedness due under this
         Indenture and the Notes, equally and ratably with (or prior to in the
         case of Liens with respect to Subordinated Obligations of the Parent or
         the Subsidiary Issuer) the Indebtedness secured by such Lien for so
         long as such Indebtedness is so secured.

                  Section 1008 Limitation on Restrictions on Distributions from
Restricted Subsidiaries

                  (o) The Parent will not, and will not permit any Restricted
         Subsidiary to, create or otherwise cause or permit to exist or become
         effective any consensual encumbrance or consensual restriction on the
         ability of any Restricted Subsidiary to:

                           (1)      pay dividends or make any other
                                    distributions on its Capital Stock or pay
                                    any Indebtedness or other obligations owed
                                    to the Parent or any Restricted Subsidiary
                                    (it being understood that the priority of
                                    any Preferred Stock in receiving dividends
                                    or liquidating distributions prior to
                                    dividends or liquidating distributions being
                                    paid on Common Stock shall not be deemed a
                                    restriction on the ability to make
                                    distributions on Capital Stock);

                           (2)      make any loans or advances to the Parent or
                                    any Restricted Subsidiary (it being
                                    understood that the subordination of loans
                                    or advances made to the Parent or any
                                    Restricted Subsidiary to other Indebtedness
                                    Incurred by the Parent or any Restricted
                                    Subsidiary shall not be deemed a restriction
                                    on the ability to make loans or advances);
                                    or

                           (3)      transfer any of its property or assets to
                                    the Parent or any Restricted Subsidiary.

                  (p) The foregoing provisions of Section 1008(a) will not
         prohibit:

                           (1)      any encumbrance or restriction pursuant to
                                    an agreement in effect at or entered into on
                                    the date of this Indenture, including,
                                    without limitation, this Indenture and the
                                    Credit Facility in effect on such date;

                           (2)      any encumbrance or restriction with respect
                                    to a Restricted Subsidiary pursuant to an
                                    agreement relating to any Capital Stock or
                                    Indebtedness Incurred by a Restricted
                                    Subsidiary on or before the date on which
                                    such Restricted Subsidiary was acquired by
                                    the Parent (other than Capital Stock or

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<PAGE>
                                    Indebtedness Incurred as consideration in,
                                    or to provide all or any portion of the
                                    funds utilized to consummate, the
                                    transaction or series of related
                                    transactions pursuant to which such
                                    Restricted Subsidiary became a Restricted
                                    Subsidiary or was acquired by the Parent or
                                    in contemplation of the transaction) and
                                    outstanding on such date;

                           (3)      any encumbrance or restriction with respect
                                    to a Restricted Subsidiary pursuant to an
                                    agreement effecting a refunding, replacement
                                    or refinancing of Indebtedness Incurred
                                    pursuant to an agreement referred to in
                                    Section 1008(b)(1), Section 1008(b)(2), this
                                    Section 1008(b)(3) or Section 1008(b)(4) or
                                    contained in any amendment to an agreement
                                    referred to in Section 1008(b)(1), Section
                                    1008(b)(2), this Section 1008(b)(3) or
                                    Section 1008(b)(4); provided, however, that
                                    the encumbrances and restrictions with
                                    respect to such Restricted Subsidiary
                                    contained in any such agreement are no less
                                    favorable in any material respect to the
                                    Holders of the Notes than the encumbrances
                                    and restrictions contained in such
                                    agreements referred to in Section
                                    1008(b)(1), Section 1008(b)(2) or Section
                                    1008(b)(4) on the Issue Date or the date
                                    such Restricted Subsidiary became a
                                    Restricted Subsidiary, whichever is
                                    applicable;

                           (4)      in the case of Section 1008(a)(3), any
                                    encumbrance or restriction:

                                    (a)     that restricts in a customary manner
                                            the subletting, assignment or
                                            transfer of any property or asset
                                            that is subject to a lease, farm-in
                                            agreement or farm-out agreement,
                                            license or similar contract, or the
                                            assignment or transfer of any such
                                            lease, license or other contract;

                                    (b)     contained in mortgages, pledges or
                                            other security agreements permitted
                                            under this Indenture securing
                                            Indebtedness of the Parent or a
                                            Restricted Subsidiary to the extent
                                            such encumbrances or restrictions
                                            restrict the transfer of the
                                            property subject to such mortgages,
                                            pledges or other security
                                            agreements;

                                    (c)     pursuant to customary provisions
                                            restricting dispositions of real
                                            property interests set forth in

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<PAGE>
                                            any reciprocal easement agreements
                                            of the Parent or any Restricted
                                            Subsidiary; or

                                    (d)     with respect to the disposition or
                                            distribution of assets or property
                                            in operating agreements, joint
                                            venture agreements, development
                                            agreements, area of mutual interest
                                            agreements and other agreements that
                                            are customary in the Oil and Gas
                                            Business and entered into in the
                                            ordinary course of business;

                           (5)      (a)     purchase money obligations for
                                            property acquired in the ordinary
                                            course of business and (b)
                                            Capitalized Lease Obligations
                                            permitted under this Indenture, in
                                            each case, that impose encumbrances
                                            or restrictions of the nature
                                            described in Section 1008(a)(3) on
                                            the property so acquired;

                           (6)      any restriction with respect to a Restricted
                                    Subsidiary (or any of its property or
                                    assets) imposed pursuant to an agreement
                                    entered into for the direct or indirect sale
                                    or disposition of all or substantially all
                                    the Capital Stock or assets of such
                                    Restricted Subsidiary (or the property or
                                    assets that are subject to such restriction)
                                    pending the closing of such sale or
                                    disposition;

                           (7)      customary provisions in joint venture
                                    agreements and other similar agreements
                                    entered into in the ordinary course of
                                    business;

                           (8)      net worth provisions in leases and other
                                    agreements entered into by the Parent or any
                                    Restricted Subsidiary in the ordinary course
                                    of business; and

                           (9)      encumbrances or restrictions arising or
                                    existing by reason of applicable law or any
                                    applicable rule, regulation or order.

                  Section 1009  Limitation on Sales of Assets and Subsidiary
Stock

                  (q) The Parent will not, and will not permit any of its
         Restricted Subsidiaries to, make any Asset Disposition unless:

                           (1)      the Parent or such Restricted Subsidiary, as
                                    the case may be, receives consideration at
                                    least equal to the fair market value (such
                                    fair market value to be determined on the
                                    date of contractually agreeing to such Asset
                                    Disposition), as determined in good faith by
                                    the Board of Directors in the case of an
                                    Asset Disposition for consideration
                                    exceeding

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<PAGE>
                                    $20 million (including as to the value of
                                    all non cash consideration), of the shares
                                    and assets subject to such Asset
                                    Disposition;

                           (2)      at least 75% of the consideration from such
                                    Asset Disposition received by the Parent or
                                    such Restricted Subsidiary, as the case may
                                    be, is in the form of cash or Cash
                                    Equivalents; and

                           (3)      an amount equal to 100% of the Net Available
                                    Cash from such Asset Disposition is applied
                                    by the Parent or such Restricted Subsidiary,
                                    as the case may be:

                                    (i)     first, to the extent the Parent or
                                            any Restricted Subsidiary, as the
                                            case may be, elects (or is required
                                            by the terms of any Senior
                                            Indebtedness), to prepay, repay or
                                            purchase Senior Indebtedness or
                                            Indebtedness of a Restricted
                                            Subsidiary (in each case other than
                                            Indebtedness owed to the Parent or
                                            an Affiliate of the Parent) within
                                            365 days from the later of the date
                                            of such Asset Disposition or the
                                            receipt of such Net Available Cash;
                                            provided, however, that, in
                                            connection with any prepayment,
                                            repayment or purchase of
                                            Indebtedness pursuant to this clause
                                            (a), the Parent or such Restricted
                                            Subsidiary will retire such
                                            Indebtedness and will cause the
                                            related commitment (if any) to be
                                            permanently reduced in an amount
                                            equal to the principal amount so
                                            prepaid, repaid or purchased; and

                                    (ii)    second, to the extent of the balance
                                            of such Net Available Cash after
                                            application in accordance with
                                            clause (a), to the extent the Parent
                                            or such Restricted Subsidiary
                                            elects, to invest in Additional
                                            Assets within 365 days from the
                                            later of the date of such Asset
                                            Disposition or the receipt of such
                                            Net Available Cash;

                                    provided that pending the final application
                                    of any such Net Available Cash in accordance
                                    with clause (i) or clause (ii) above, the
                                    Parent and its Restricted Subsidiaries may
                                    temporarily reduce Indebtedness or otherwise
                                    invest such Net Available Cash in any manner
                                    not prohibited by this Indenture.


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<PAGE>
                  (b) Any Net Available Cash from Asset Dispositions that are
         not applied or invested as provided in the preceding paragraph will be
         deemed to constitute "Excess Proceeds." On the 366th day after an Asset
         Disposition, if the aggregate amount of Excess Proceeds exceeds $10
         million, a "triggering event" shall be deemed to have occurred, which
         will result in the obligation of the Parent and the Subsidiary Issuer
         to make an offer ("Asset Disposition Offer") to all Holders of Units,
         and to the extent required by the terms of other Senior Subordinated
         Indebtedness, to all holders of other Senior Subordinated Indebtedness
         outstanding with similar provisions requiring the Parent and the
         Subsidiary Issuer to make an offer to purchase such Senior Subordinated
         Indebtedness with the proceeds from any Asset Disposition ("Pari Passu
         Notes"), to purchase the maximum number of Units, and the maximum
         principal amount of any such Pari Passu Notes to which the Asset
         Disposition Offer applies that may be purchased out of the Excess
         Proceeds, at an offer price in cash in an amount equal to 100% of the
         principal amount of the Notes comprising the Units and of the Pari
         Passu Notes plus accrued and unpaid interest to the date of purchase,
         in accordance with the procedures set forth in this Indenture or the
         agreements governing the Pari Passu Notes, as applicable, as whole
         Units in the case of the Units and in integral multiples of $1,000 in
         the case of the Pari Passu Notes. To the extent that the aggregate
         amount of Notes comprising Units and Pari Passu Notes so validly
         tendered and not properly withdrawn pursuant to an Asset Disposition
         Offer is less than the Excess Proceeds, the Parent or the Subsidiary
         Issuer may use any remaining Excess Proceeds for general corporate
         purposes, subject to other covenants contained in this Indenture. If
         the aggregate principal amount of Notes comprising Units surrendered by
         Holders thereof and other Pari Passu Notes surrendered by holders or
         lenders, collectively, exceeds the amount of Excess Proceeds, the
         Trustee shall select the Units and Pari Passu Notes to be purchased on
         a pro rata basis on the basis of the aggregate principal amount of
         tendered Units and Pari Passu Notes. Upon completion of such Asset
         Disposition Offer, the amount of Excess Proceeds shall be reset at
         zero.

                  (c) The Asset Disposition Offer will remain open for a period
         of 20 Business Days following its commencement, except to the extent
         that a longer period is required by applicable law (the "Asset
         Disposition Offer Period"). No later than five Business Days after the
         termination of the Asset Disposition Offer Period (the "Asset
         Disposition Purchase Date"), the Parent and the Subsidiary Issuer will
         purchase the principal amount of Units and Pari Passu Notes required to
         be purchased pursuant to this covenant (the "Asset Disposition Offer
         Amount") or, if less than the Asset Disposition Offer Amount has been
         so validly tendered, all Units and Pari Passu Notes validly tendered in
         response to the Asset Disposition Offer.

                  (d) If the Asset Disposition Purchase Date is on or after an
         interest record date and on or before the related interest payment
         date, any accrued and unpaid interest will be paid to the Person in
         whose name a Note is registered at the close of business on such record
         date, and no additional interest will be payable to Holders who tender
         Units pursuant to the Asset Disposition Offer.


                                       62
<PAGE>
                  (e) On or before the Asset Disposition Purchase Date, the
         Parent and the Subsidiary Issuer will, to the extent lawful, accept for
         payment, on a pro rata basis to the extent necessary, the Asset
         Disposition Offer Amount of Units, and Pari Passu Notes or portions of
         Units and Pari Passu Notes so validly tendered and not properly
         withdrawn pursuant to the Asset Disposition Offer, or if less than the
         Asset Disposition Offer Amount has been validly tendered and not
         properly withdrawn, all Units and Pari Passu Notes so validly tendered
         and not properly withdrawn, as whole Units in the case of the Units and
         in integral multiples of $1,000 in the case of the Pari Passu Notes.
         The Parent and the Subsidiary Issuer will deliver to the Trustee an
         Officers' Certificate stating that the Units were accepted for payment
         by the Parent and the Subsidiary Issuer in accordance with the terms of
         this covenant and, in addition, the Parent and the Subsidiary Issuer
         will deliver all certificates and notes required, if any, by the
         agreements governing the Pari Passu Notes. The Parent, the Subsidiary
         Issuer or the Paying Agent, as the case may be, will promptly (but in
         any case not later than five Business Days after termination of the
         Asset Disposition Offer Period) mail or deliver to each tendering
         Holder of Units or holder or lender of Pari Passu Notes, as the case
         may be, an amount equal to the purchase price of the Notes comprising
         the Units or Pari Passu Notes so validly tendered and not properly
         withdrawn by such holder or lender, as the case may be, and accepted by
         the Parent and the Subsidiary Issuer for purchase, and the Parent and
         the Subsidiary Issuer will promptly issue new Notes comprising a new
         Unit, and the Trustee, upon delivery of an Officers' Certificate from
         the Parent will authenticate and mail or deliver such new Units to such
         Holder, in a principal amount equal to any unpurchased portion of the
         Units surrendered; provided that such new Unit will be a whole Unit or
         an integral multiple of a whole Unit. For the sake of clarification, in
         no event shall such new Notes be considered to be a new issuance of
         Indebtedness by the Parent or the Subsidiary Issuer. In addition, the
         Parent and the Subsidiary Issuer will take any and all other actions
         required by the agreements governing the Pari Passu Notes. Any Unit not
         so accepted will be promptly mailed or delivered by the Parent and the
         Subsidiary Issuer to the Holder thereof. The Parent and the Subsidiary
         Issuer will publicly announce the results of the Asset Disposition
         Offer on the Asset Disposition Purchase Date.

                  (f) For the purposes of this Section 1009, the following will
         be deemed to be cash:

                           (1)      the assumption by the transferee of
                                    Indebtedness (other than Subordinated
                                    Obligations or Disqualified Stock) of the
                                    Parent or Indebtedness of a Restricted
                                    Subsidiary and the release of the Parent or
                                    such Restricted Subsidiary from all
                                    liability on such Indebtedness in connection
                                    with such Asset Disposition (in which case
                                    the Parent will, without further action, be
                                    deemed to have applied such deemed cash to
                                    Indebtedness in accordance with Section
                                    1009(a)(3)(i); and


                                       63
<PAGE>
                  (2)   securities, notes or other obligations received by the
                        Parent or any Restricted Subsidiary of the Parent from
                        the transferee that are converted by the Parent or such
                        Restricted Subsidiary into cash within 60 days.

      (g) The Parent will not, and will not permit any Restricted Subsidiary to,
engage in any Asset Swaps, unless:

                  (1)   in the event such Asset Swap involves the transfer by
                        the Parent or any Restricted Subsidiary of assets having
                        an aggregate fair market value, as determined by the
                        Board of Directors of the Parent in good faith, in
                        excess of $10 million, the terms of such Asset Swap have
                        been approved by a majority of the members of the Board
                        of Directors of the Parent; and

                  (2)   in the event such Asset Swap involves the transfer by
                        the Parent or any Restricted Subsidiary of assets having
                        an aggregate fair market value, as determined by the
                        Board of Directors of the Parent in good faith, in
                        excess of $25 million, the Parent has received a written
                        opinion from an independent investment banking firm of
                        nationally recognized standing that such Asset Swap is
                        fair to the Parent or such Restricted Subsidiary, as the
                        case may be, from a financial point of view.

      (h) The Parent and the Subsidiary Issuer will comply, to the extent
applicable, with the requirements of Section 14(e) of the Exchange Act and any
other securities laws or regulations in connection with the repurchase of Units
pursuant to this Indenture. To the extent that the provisions of any securities
laws or regulations conflict with provisions of this covenant, the Parent and
the Subsidiary Issuer will comply with the applicable securities laws and
regulations and will not be deemed to have breached its obligations under this
Indenture by virtue of any conflict. The provisions under this Indenture
relative to the Parent's and the Subsidiary Issuer's obligation to make an offer
to repurchase Units as a result of an Asset Disposition may be waived or
modified with the written consent of the Holders of a majority in principal
amount of the Notes comprising the Units.

      Section 1010 Limitation on Affiliate Transactions

      (a) The Parent will not, and will not permit any of its Restricted
Subsidiaries to, directly or indirectly, enter into or conduct any transaction
(including the purchase, sale, lease or exchange of any property or the
rendering of any service) with any Affiliate of the Parent (an "Affiliate
Transaction") unless:



                                       64
<PAGE>
                  (1)   the terms of such Affiliate Transaction are no less
                        favorable to the Parent or such Restricted Subsidiary,
                        as the case may be, than those that could be obtained in
                        a comparable transaction at the time of such transaction
                        in arm's length dealings with a Person who is not such
                        an Affiliate;

                  (2)   in the event such Affiliate Transaction involves an
                        aggregate consideration in excess of $5 million, an
                        Officers' Certificate certifying that such Affiliate
                        Transaction satisfies the criteria in clause (a)(1) of
                        this Section 1010 shall have been delivered to the
                        Trustee;

                  (3)   in the event such Affiliate Transaction involves an
                        aggregate consideration in excess of $10 million, the
                        terms of such transaction have been approved by a
                        majority of the members of the Board of Directors of the
                        Parent and by a majority of the members of such Board
                        having no personal stake in such transaction, if any
                        (and such majority or majorities, as the case may be,
                        determines that such Affiliate Transaction satisfies the
                        criteria in Section 1013(a)(1)); and

                  (4)   in the event such Affiliate Transaction involves an
                        aggregate consideration in excess of $25 million, the
                        Parent has received a written opinion from an
                        independent investment banking, accounting or appraisal
                        firm of nationally recognized standing that such
                        Affiliate Transaction is not materially less favorable
                        than those that might reasonably have been obtained in a
                        comparable transaction at such time on an arm's length
                        basis from a Person that is not an Affiliate.

      (b) The foregoing Section 1010(a) will not apply to:


                  (1)   any Restricted Payment or any Permitted Investment
                        permitted to be made pursuant to Section 1005;


                  (2)   any issuance of securities, or other payments, awards or
                        grants in cash, securities or otherwise pursuant to, or
                        the funding of, employment agreements and other
                        compensation arrangements, options to purchase Capital
                        Stock of the Parent, restricted stock plans, long-term
                        incentive plans, stock appreciation rights plans,
                        participation plans or similar employee benefits plans
                        and/or indemnity provided on behalf of officers and
                        employees approved by the Board of Directors;

                                       65
<PAGE>
                  (3)   loans or advances to employees, officers or directors in
                        the ordinary course of business of the Parent or any of
                        its Restricted Subsidiaries, in each case only as
                        permitted by Section 402 of the Sarbanes Oxley Act of
                        2002, but in any event not to exceed $2 million in the
                        aggregate outstanding at any one time with respect to
                        all loans or advances made since the Issue Date;

                  (4)   any transaction between the Parent and a Restricted
                        Subsidiary or between Restricted Subsidiaries and
                        Guarantees issued by the Parent or a Restricted
                        Subsidiary for the benefit of the Parent or a Restricted
                        Subsidiary, as the case may be, in accordance with
                        Section 1004;

                  (5)   the payment of reasonable and customary fees and
                        compensation paid to, and indemnity provided on behalf
                        of, officers and directors of the Parent or any
                        Restricted Subsidiary of the Parent; and

                  (6)   the performance of obligations of the Parent or any of
                        its Restricted Subsidiaries under the terms of any
                        agreement to which the Parent or any of its Restricted
                        Subsidiaries is a party as of or on the Issue Date and
                        identified on a schedule to this Indenture on the Issue
                        Date, as these agreements may be amended, modified,
                        supplemented, extended or renewed from time to time;
                        provided, however, that any future amendment,
                        modification, supplement, extension or renewal entered
                        into after the Issue Date will be permitted to the
                        extent that its terms are not more disadvantageous to
                        the Holders of the Units than the terms of the
                        agreements in effect on the Issue Date.

      Section 1011 Limitation on Sale of Capital Stock of Restricted
Subsidiaries

      (a) The Parent will not, and will not permit any Restricted Subsidiary of
the Parent to, transfer, convey, sell, lease or otherwise dispose of any Voting
Stock of any Restricted Subsidiary or to issue any of the Voting Stock of a
Restricted Subsidiary (other than, if necessary, shares of its Voting Stock
constituting directors' qualifying shares) to any Person except:

                  (1)   to the Parent or a Wholly Owned Subsidiary; or

                  (2)   in compliance with Section 1009 and immediately after
                        giving effect to such issuance or sale, such Restricted
                        Subsidiary would continue to be a Restricted Subsidiary.




                                       66
<PAGE>
      (b) Notwithstanding the preceding paragraph, the Parent may sell all the
Voting Stock of a Restricted Subsidiary as long as the Parent complies with
Section 1009.

      Section 1012 SEC Reports

      Notwithstanding that the Parent may not be subject to the reporting
requirements of Section 13 or 15(d) of the Exchange Act, to the extent permitted
by the Exchange Act, the Parent will file with the SEC, and make available to
the Trustee and the registered Holders of the Units, the annual reports and the
information, documents and other reports (or copies of such portions of any of
the foregoing as the SEC may by rules and regulations prescribe) that are
specified in Sections 13 and 15(d) of the Exchange Act within the time periods
specified therein. In the event that the Parent is not permitted to file such
reports, documents and information with the SEC pursuant to the Exchange Act,
the Parent will nevertheless make available such Exchange Act information to the
Trustee and the Holders of the Units as if the Parent were subject to the
reporting requirements of Section 13 or 15(d) of the Exchange Act within the
time periods specified therein.

      Section 1013 Future Subsidiary Guarantees

      The Parent will not permit any Restricted Subsidiary (other than a Foreign
Subsidiary) to Guarantee the payment of any Indebtedness of the Parent or any
other Subsidiary unless such Restricted Subsidiary simultaneously executes and
delivers a supplemental indenture to this Indenture providing for a Subsidiary
Guarantee of such Restricted Subsidiary pursuant to this Indenture the form of
which is attached hereto as Exhibit E.

      Notwithstanding the foregoing and the other provisions of this Indenture,
in the event a Subsidiary Guarantor is sold or disposed of (whether by merger,
consolidation, the sale of its Capital Stock or the sale of all or substantially
all of its assets (other than by lease) and whether or not the Subsidiary
Guarantor is the surviving corporation in such transaction) to a Person which is
not the Parent or a Restricted Subsidiary, such Subsidiary Guarantor will be
released from its obligations under its Subsidiary Guarantee if:

                  (1)   the sale or other disposition is in compliance with this
                        Indenture, including Section 1009 and Section 1011; and


                  (2)   the Guarantee which required the creation of the
                        Subsidiary Guarantee is released or discharged, except a
                        discharge or release by or as a result of payment under
                        such Guarantee.

      In addition, a Subsidiary Guarantor will be released from its obligations
under this Indenture and the Subsidiary Guarantee if the Parent designates such
Subsidiary as an Unrestricted Subsidiary in accordance with this Indenture.

      Section 1014 Limitation on Lines of Business



                                       67
<PAGE>
      The Parent will not, and will not permit any Restricted Subsidiary to,
engage in any business other than the Oil and Gas Business, except to such
extent as would not be material in the opinion of the Board of Directors of the
Parent (which opinion shall be reasonable and made in good faith) to the Parent
and its Restricted Subsidiaries taken as a whole.

      Section 1015 Payments for Consent

      None of the Parent, the Subsidiary Issuer or any of the Restricted
Subsidiaries will, directly or indirectly, pay or cause to be paid any
consideration, whether by way of interest, fees or otherwise, to any Holder of
any Notes or Units for or as an inducement to any consent, waiver or amendment
of any of the terms or provisions of this Indenture or the Notes unless such
consideration is offered to be paid or is paid to all Holders of the Notes or
Units that consent, waive or agree to amend in the time frame set forth in the
solicitation documents relating to such consent, waiver or amendment.

      Section 1016 [Reserved]

      Section 1017 Change of Control

      If a Change of Control occurs, then such Change of Control shall
constitute a "triggering event" which shall result in the obligation of the
Parent and the Subsidiary Issuer make an offer to repurchase from each Holder in
all or any part of such holder's Units (as whole Units or an integral multiple
thereof), at a purchase price in cash equal to 101% of the principal amount of
the Notes comprising the Units plus accrued and unpaid interest, if any, to the
date of purchase (subject to the right of Holders of record on the relevant
record date to receive interest due on the relevant interest payment date).

      Within 30 days following any Change of Control, the Parent and the
Subsidiary Issuer will mail a notice (the "Change of Control Offer") to each
Holder with a copy to the Trustee stating: (1) that a Change of Control has
occurred and that such Holder has the right to require the Parent and the
Subsidiary Issuer to purchase such holder's Units at a purchase price in cash
equal to 101% of the principal amount of the Notes comprising such Units plus
accrued and unpaid interest, if any, to the date of purchase (subject to the
right of Holders of record on a record date to receive interest on the relevant
interest payment date) (the "Change of Control Payment"); (2) the repurchase
date (which shall be no earlier than 30 days nor later than 60 days from the
date such notice is mailed) (the "Change of Control Payment Date"); and (3) the
procedures determined by the Parent and the Subsidiary Issuer, consistent with
this Indenture, that a Holder must follow in order to have its Units
repurchased.

      On or before the Change of Control Payment Date, the Parent and the
Subsidiary Issuer will, to the extent lawful: (1) accept for payment all Units
(as whole Units or in integral multiples thereof) properly tendered pursuant to
the

                                       68
<PAGE>
Change of Control Offer; (2) deposit with the Paying Agent an amount equal to
the Change of Control Payment in respect of all Units so tendered; and (3)
deliver or cause to be delivered to the Trustee the Units so accepted together
with an Officers' Certificate stating the number of Units being purchased by the
Parent and the Subsidiary Issuer.

      The Paying Agent will promptly mail to each Holder of Units so tendered
the Change of Control Payment for such Units, and the Trustee will promptly
authenticate and mail (or cause to be transferred by book entry) to each Holder
Notes comprising new Units equal in principal amount to, and evidencing the same
Indebtedness as any unpurchased portion of the Units surrendered, if any;
provided that each such Unit will be as whole Units or an integral multiple
thereof.

      If the Change of Control Payment Date is on or after an interest record
date and on or before the related interest payment date, any accrued and unpaid
interest, if any, will be paid to the Person in whose name a Unit is registered
at the close of business on such record date, and no additional interest will be
payable to Holders who tender pursuant to the Change of Control Offer.

      Prior to mailing a Change of Control Offer, and as a condition to such
mailing (i) all Senior Indebtedness must be repaid in full, or the Parent and
the Subsidiary Issuer must offer to repay all Senior Indebtedness and make
payment to the Holders that accept such offer and obtain waivers of any event of
default from the remaining holders of such Senior Indebtedness whose holders
accept such offer or (ii) the requisite holders of each issue of Senior
Indebtedness shall have consented to such Change of Control Offer being made.
The Parent and the Subsidiary Issuer jointly covenant to effect such repayment
or obtain such consent within 30 days following any Change of Control, it being
a Default of this Section 1017 if the Parent or the Subsidiary Issuer fails to
comply with this Section.

      Neither the Parent nor the Subsidiary Issuer will be required to make a
Change of Control Offer upon a Change of Control if a third party makes the
Change of Control Offer in the manner, at the times and otherwise in compliance
with the requirements set forth in this Indenture applicable to a Change of
Control Offer made by the Parent and the Subsidiary Issuer and purchases all
Units validly tendered and not withdrawn under such Change of Control Offer.

      The Parent and the Subsidiary Issuer will comply, to the extent
applicable, with the requirements of Section 14(e) of the Exchange Act and any
other securities laws or regulations in connection with the repurchase of Units
pursuant to this Section 1017. To the extent that the provisions of any
securities laws or regulations conflict with provisions of this Indenture, the
Parent and the Subsidiary Issuer will comply with the applicable securities laws
and regulations and will not be deemed to have breached its obligations
described in this Indenture by virtue of the conflict.



                                       69
<PAGE>
      Section 1018 Statement by Officers as to Default

      (a) The Parent and the Subsidiary Issuer each will deliver to the Trustee,
within 90 days after the end of each fiscal year of the Parent and the
Subsidiary Issuer ending after the date hereof, an Officer's Certificate,
stating whether or not to the best knowledge of the signers thereof the Parent
or the Subsidiary Issuer, as the case may be, is in Default in the performance
and observance of any of the terms, provisions and conditions of this Indenture
(without regard to any period of grace or requirement of notice provided
hereunder) and, if the Parent or the Subsidiary Issuer, as the case may be,
shall be in Default, specifying all such Defaults and the nature and status
thereof of which they may have knowledge.

      (b) The Parent or the Subsidiary Issuer, as the case may be, shall deliver
to the Trustee, as soon as possible and in any event within five days after the
Parent or the Subsidiary Issuer, as the case may be, becomes aware or should
reasonably become aware of the occurrence of a Default or an Event of Default,
an Officer's Certificate setting forth the details of such Default or Event of
Default, and the action which the Parent or the Subsidiary Issuer, as the case
may be, proposes to take with respect thereto.

      Section 1019 Effectiveness of Covenants

      The covenants described under Sections 1004, Section 1005, Section 1008,
Section 1009, Section 1010, Section 1011, Section 1014 and clause (3) under
Section 801 (collectively, the "Suspended Covenants"), will no longer be in
effect upon (a) both the Parent Notes and the Subsidiary Notes having an
Investment Grade Rating from both S&P and Moody's and (b) no Default or Event of
Default having occurred and continuing under this Indenture. In the event that
the Parent, the Subsidiary Issuer and the Restricted Subsidiaries are not
subject to the Suspended Covenants for any period of time as a result of the
preceding sentence and, subsequently, one or both of the rating agencies named
above withdraws its ratings or downgrades the rating assigned to the Notes below
the required Investment Grade Ratings or a Default or Event of Default occurs
and is continuing, then the Parent, the Subsidiary Issuer and the Restricted
Subsidiaries will thereafter again be subject to the Suspended Covenants and
compliance with the Suspended Covenants, unless and until the conditions set
forth in the previous sentence are again satisfied. Notwithstanding that the
Suspended Covenants may be reinstated, no default will be deemed to have
occurred as a result of failure to comply with the Suspended Covenants during
such suspension. Compliance with the Suspended Covenants with respect to
Restricted Payments made after the time of such withdrawal, downgrade, Default
or Event of Default will be calculated pursuant to Section 1005 as though such
covenant had been in effect during the entire period of time from the date the
Notes are issued."



                                       70
<PAGE>
      SECTION 2.4. SUCCESSOR COMPANY

      Article Eight of the Original Indenture is supplemented, amended and
restated to read in its entirety as follows.

                                 "Article Eight

                                SUCCESSOR COMPANY

            Section 801 Merger and Consolidation

            The Parent will not consolidate with or merge with or into, or
      convey, transfer or lease all or substantially all its assets to, any
      Person, unless:

                  (1) the resulting, surviving or transferee Person (the
            "Successor Company") will be a corporation, partnership, trust or
            limited liability company organized and existing under the laws of
            the United States of America, any State of the United States or the
            District of Columbia and the Successor Company (if not the Parent)
            will expressly assume, by supplemental indenture, executed and
            delivered to the Trustee, in form satisfactory to the Trustee, all
            the obligations of the Parent under the Parent Notes, the Parent
            Guarantee and this Indenture;

                  (2) immediately after giving effect to such transaction (and
            treating any Indebtedness that becomes an obligation of the
            Successor Company or any Subsidiary of the Successor Company as a
            result of such transaction as having been Incurred by the Successor
            Company or such Subsidiary at the time of such transaction), no
            Default or Event of Default shall have occurred and be continuing;

                  (3) immediately after giving effect to such transaction, the
            Successor Company would be able to Incur at least an additional
            $1.00 of Indebtedness pursuant to Section 1004(a); and


                  (4) the Parent shall have delivered to the Trustee an
            Officers' Certificate and an Opinion of Counsel, each stating that
            such consolidation, merger or transfer and such supplemental
            indenture (if any) comply with this Indenture.

            For purposes of this Section 801, the sale, lease, conveyance,
      assignment, transfer, or other disposition of all or substantially all of
      the properties and assets of one or more Subsidiaries of the Parent, which
      properties and assets, if held by the Parent instead of such Subsidiaries,
      would constitute all or substantially all of the properties and assets of
      the Parent on a consolidated basis, shall be deemed to be the transfer of
      all or substantially all of the properties and assets of the Parent.

            The Successor Company will succeed to, and be substituted for, and
      may exercise every right and power of, the Parent under this Indenture.



                                       71
<PAGE>
            Notwithstanding the preceding clause (3) of this Section 801, (x)
      any Restricted Subsidiary of the Parent may consolidate with, merge into
      or transfer all or part of its properties and assets to the Parent and (y)
      the Parent may merge with an Affiliate incorporated solely for the purpose
      of reincorporating the Parent in another jurisdiction to realize tax
      benefits; provided that, in the case of a Restricted Subsidiary that
      merges into the Parent, the Parent will not be required to comply with the
      preceding clause (4) of this Section 801.

            The Subsidiary Issuer will not consolidate with or merge with or
      into, or convey, transfer or lease all or substantially all its assets to,
      any Person other than the Parent or any Restricted Subsidiary.

            The Subsidiary Issuer may consolidate with or merge with or into, or
      convey, transfer or lease all or substantially all its assets to the
      Parent or any Restricted Subsidiary, if such Person will expressly assume,
      by supplemental indenture, executed and delivered to the Trustee, in form
      satisfactory to the Trustee, all the obligations of the Subsidiary Issuer
      under the Subsidiary Notes and this Indenture. Thereupon, the Subsidiary
      Issuer will be fully released from its obligations under the Subsidiary
      Notes and the Parent or such Restricted Subsidiary, as applicable, will
      succeed to, and be substituted for, and may exercise every right and power
      of, the Subsidiary Issuer under the Subsidiary Notes and this Indenture
      and, in the case of a transaction in which the Parent is such successor,
      the Parent Guarantee will be automatically released, without any further
      action.

            Section 802 Assumption By Parent of Subsidiary Notes

            At any time at the joint option of the Parent and the Subsidiary
      Issuer, the Parent may assume, and the Subsidiary Issuer may assign, all
      of the Subsidiary Issuer's obligations with respect to all or, from time
      to time, part of the Subsidiary Notes, by supplemental indenture, executed
      and delivered to the Trustee, in form satisfactory to the Trustee.

            Upon such assumption, the Subsidiary Issuer will be fully released
      from its obligations under the Units and the Subsidiary Notes that have
      been so assigned and assumed and the Parent will succeed to the
      obligations of, and be substituted for, and may exercise every right and
      power of, the Subsidiary Issuer under this Indenture with respect to the
      Units and the Subsidiary Notes so assumed, and the Parent Guarantee will
      be automatically released, without any further action, with respect to the
      Units and the Subsidiary Notes so assumed."

      SECTION 2.5. REDEMPTION

      Article Eleven of each of the Original Indentures is supplemented, amended
and restated to read in its entirety as follows:

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<PAGE>
                                 "Article Eleven

                               REDEMPTION OF UNITS

            Section 1101 Applicability of Article

            (a) On and after September 15, 2008 and prior to maturity, the
      Parent and the Subsidiary Issuer jointly may redeem all or, from time to
      time, part of the Notes as whole Units, upon not less than 30 nor more
      than 60 days' notice mailed to each Holder of Units at such Holder's
      address appearing in the Register, in whole Units or an integral multiple
      of a whole Unit, at the following Redemption Prices (expressed as
      percentages of the principal amount) plus accrued and unpaid interest on
      the Notes, if any, to but excluding the Redemption Date (subject to the
      right of Holders of record on the relevant regular record date to receive
      interest due on an Interest Payment Date that is on or prior to the
      Redemption Date), if redeemed during the 12-month period beginning
      September 15 of the years indicated:
<TABLE>
<CAPTION>
YEAR                                                        REDEMPTION PRICE

<S>                                                         <C>
2008..............................................             103.625%
2009..............................................             102.417%
2010..............................................             101.208%
2011 and thereafter ..............................             100.000%
</TABLE>

            (b) Prior to September 15, 2006, the Parent and the Subsidiary
      Issuer jointly may on one or more occasions redeem up to an aggregate
      amount equal to 35% of the original principal amount of the Notes
      compromising the Units, as whole Units, including any Additional Units,
      with the Net Cash Proceeds of one or more Equity Offerings at a redemption
      price of 107.250% of the principal amount of the Notes comprising the
      Units, plus accrued and unpaid interest, if any, to the redemption date
      (subject to the right of Holders of record on the relevant record date to
      receive interest due on the relevant interest payment date); provided,
      that (i) there is a Public Market at the time of such redemption, (ii) at
      least 65% of the original principal amount of the Notes comprising the
      Units, including any Additional Units, remains outstanding after each such
      redemption and (iii) the redemption occurs within 90 days after the
      closing of such Equity Offering.

            (c) In the case of any partial redemption, selection of the Notes,
      as whole Units, for redemption will be made by the Trustee in compliance
      with the requirements of the principal national securities exchange, if
      any, on which the Units or Notes are listed or, if the Units and Notes are
      not listed, then on a pro rata basis, by lot or by such other method as
      the Trustee in its sole discretion will deem to be fair and appropriate,
      although no Unit will be redeemed in part. Notes and Units in a principal
      amount equal to, and representing the same Indebtedness as, the unredeemed
      portion thereof will be issued in the name of the Holder thereof upon
      cancellation of the original Notes and Units.

                                       73
<PAGE>
            (d) The Notes, as whole Units, will be subject to redemption at the
      joint option of the Parent and the Subsidiary Issuer, as a whole but not
      in part, at any time upon not fewer than 30 nor more than 60 days' notice
      mailed to each Holder of Units at the addresses appearing in the Register
      at a redemption price equal to 100% of the principal amount of the Notes
      compromising the Units plus accrued interest to but excluding the
      Redemption Date if the Subsidiary Issuer has become or would become
      obligated to pay on the next date on which any amount would be payable
      under or with respect to the Subsidiary Notes, any Additional Amounts as a
      result of any change or amendment to the laws (or regulations promulgated
      thereunder) of Canada (or any political subdivision or taxing authority
      thereof or therein) (collectively, a "Taxing Authority"), or any change in
      or amendment to any official position or administration or assessing
      practices regarding the application or interpretation of such laws or
      regulations, which change or amendment is announced or becomes effective
      on or after the date of this Indenture.

            Section 1102 Election to Redeem; Notice to Trustee

            The joint election of the Parent and the Subsidiary Issuer to redeem
      any Notes, as whole Units, pursuant to Section 1101 shall be evidenced by
      a Board Resolution of both the Parent and the Subsidiary Issuer. In case
      of any redemption at the election of the Parent and the Subsidiary Issuer,
      the Parent and the Subsidiary Issuer shall, upon not later than the
      earlier of the date that is 45 days prior to the Redemption Date fixed by
      the Parent and the Subsidiary Issuer or the date on which notice is given
      to the Holders unless a shorter notice shall be satisfactory to the
      Trustee), notify the Trustee of such Redemption Date, of the principal
      amount of Notes, as whole Units, to be redeemed and shall deliver to the
      Trustee such documentation and records as shall enable the Trustee to
      select the Notes to be redeemed pursuant to Section 1103.

            Section 1103 Selection by Trustee of Units to Be Redeemed

            If less than all the Units are to be redeemed at the joint option of
      the Parent and the Subsidiary Issuer, the particular Units to be redeemed
      shall be selected not more than 60 days prior to the Redemption Date by
      the Trustee from the outstanding Notes not previously called for
      redemption, by such method as the Trustee in its sole discretion shall
      deem to be fair and appropriate in accordance with methods generally used
      by fiduciaries in similar circumstances at the time of selection (and in
      such manner as complies with applicable legal requirements) and which may
      provide for the selection for redemption of Units; provided, however, that
      (i) Units that the Trustee selects shall be whole Units or an integral
      multiple of a whole Unit and (ii) no such partial redemption shall reduce
      the portion of the total principal amount of the Parent Notes and the
      Subsidiary Note comprising of a Unit not redeemed to less than $1,000.
      Units in an amount equal to, and representing the same Indebtedness as,
      the unredeemed portion thereof will be issued in the name of the Holder
      thereof upon cancellation of the original Units.



                                       74
<PAGE>
            The Trustee shall promptly notify the Parent and the Subsidiary
      Issuer in writing of the Units selected for redemption.

            Section 11.04 Notice of Redemption

            Notice of redemption shall be given in the manner provided for in
      Section 3.7 not less than 30 nor more than 60 days prior to the Redemption
      Date, to each Holder of Notes and Units to be redeemed, at the address
      appearing in the Register. The Trustee shall give notice of redemption in
      the name of the Parent and the Subsidiary Issuer's expense; provided,
      however that the Parent and the Subsidiary Issuer shall deliver to the
      Trustee at least 45 days prior to the Redemption Date (unless a shorter
      notice shall be satisfactory to the trustee), an Officer's Certificate
      requesting that the Trustee give such notice as provided in the following
      items.

            All notices of redemption shall state:

                  (1)   the Redemption Date,

                  (2)   the Redemption Price and accrued interest to the
                        Redemption Date payable as provided in Section 1106, if
                        any,

                  (3)   if less than all the Units are to be redeemed, the
                        identification (and, in the case of partial redemption,
                        the principal amounts) of the particular Units, to be
                        redeemed,

                  (4)   that on the Redemption Date the Redemption Price and
                        accrued interest, if any, will become due and payable
                        upon each of the Notes to be redeemed, or the portions
                        thereof, and, if applicable, that interest thereon will
                        cease to accrue on and after said date,

                  (5)   the place or places where each such Notes, as whole
                        Units, are to be surrendered for payment of the
                        Redemption Price and accrued interest, if any.

            Notice of redemption of Notes to be redeemed as whole Units at the
      joint election of the Parent and the Subsidiary Issuer shall be given by
      the Parent and the Subsidiary Issuer, at the Parent's and the Subsidiary
      Issuer's joint request, by the Trustee in the name and at the expense of
      the Parent and the Subsidiary Issuer and shall be irrevocable.

            Section 1105 Deposit of Redemption Price

            Prior to any Redemption Date, the Parent and the Subsidiary Issuer
      shall deposit with the Trustee or with a Paying Agent (or, if the Parent
      or the Subsidiary is acting as Paying Agent, segregate and hold in trust
      as provided in Section 1.2) an amount of money sufficient to pay the
      Redemption Price of, and


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      accrued interest, if any, on, all the Notes which are to be redeemed as
      whole Units on that date.

            Section 1106 Notes Payable on Redemption Date

            Notice of redemption having been given as aforesaid, the Notes so to
      be redeemed as whole Units shall, on the Redemption Date, become due and
      payable at the Redemption Price therein specified (together with accrued
      interest, if any, to the Redemption Date), and from and after such date
      (unless the Parent or the Subsidiary Issuer shall default in the payment
      of the Redemption Price and accrued interest, if any) such Notes shall
      cease to bear interest. Upon surrender of any such Note for redemption in
      accordance with said notice, such Note shall be paid as a Unit by the
      Parent and the Subsidiary Issuer at the Redemption Price, together with
      accrued interest, if any, to the Redemption Date (subject to the rights of
      Holders of record on the relevant record date to receive interest due on
      the relevant interest payment date).

            If any Note compromising a Unit called for redemption shall not be
      so paid upon surrender thereof for redemption, the principal and any
      premium shall, until paid, bear interest from the Redemption Date at the
      rate prescribed therefor in the Note.

            Section 1107 Notes Redeemed in Part

            Any Note which is to be redeemed as a Unit only in part shall be
      surrendered at the office or agency of the Parent and the Subsidiary
      Issuer maintained for such purpose pursuant to Section 1002 (with, if the
      Parent and the Subsidiary Issuer or the Trustee so requires, due
      endorsement by, or a written instrument of transfer in form satisfactory
      to the Parent and the Subsidiary Issuer and the Trustee duly executed by,
      the Holder thereof or his attorney duly authorized in writing), and the
      Parent and the Subsidiary Issuer shall execute and the Trustee shall
      authenticate and deliver to the Holder of such Unit without service
      charge, a new Unit or Units, each having endorsed thereon the Parent
      Guarantee by the Guarantor, of any authorized denomination as requested by
      such Holder, in aggregate principal amount equal to and in exchange for
      the unredeemed portion of the principal of the Unit so surrendered,
      provided that each such new Unit will be in a whole Unit or an integral
      multiple of a whole Unit."

      SECTION 2.6. REMEDIES

      Article Five of each of the Original Indentures is supplemented, amended
and restated to read in its entirety as follows:

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<PAGE>
                                  "Article Five

                                    Remedies

            Section 501 Events of Default

            Each of the following is an "Event of Default":

            (1)   default in any payment of interest on any Note when due,
                  continued for 30 days, whether or not such payment is
                  prohibited by the provisions described under Article Fifteen;


            (2)   default in the payment of principal of or premium, if any, on
                  any Note when due at its Stated Maturity, upon optional
                  redemption, upon required repurchase, upon declaration or
                  otherwise, whether or not such payment is prohibited by the
                  provisions described under Article Fifteen;

            (3)   failure by the Parent or the Subsidiary Issuer to comply with
                  its respective obligations under Article Ten or failure by the
                  Parent to comply with its obligations under Article Thirteen;


            (4)   failure by the Parent or the Subsidiary Issuer to comply for
                  30 days after notice with any of its respective obligations
                  under Article Ten (in each case, other than a failure to
                  purchase Units which will constitute an Event of Default under
                  clause (2) of this Section 501 and other than a failure to
                  comply with Section 801 which is covered by clause (3) of this
                  Section 501);


            (5)   failure by the Parent to comply for 60 days after notice with
                  its other agreements contained in this Indenture;

            (6)   default under any mortgage, indenture or instrument under
                  which there may be issued or by which there may be secured or
                  evidenced any Indebtedness for money borrowed by the Parent or
                  any of its Restricted Subsidiaries (or the payment of which is
                  guaranteed by the Parent or any of its Restricted
                  Subsidiaries), other than Indebtedness owed to the Parent or a
                  Restricted Subsidiary, whether such Indebtedness or guarantee
                  now exists, or is created after the date of this Indenture,
                  which default:

                  (a)   is caused by a failure to pay principal of, or interest
                        or premium, if any, on such Indebtedness prior to the
                        expiration of the grace period provided in such
                        Indebtedness ("Payment Default"); or

                  (b)   results in the acceleration of such Indebtedness prior
                        to its maturity (the "cross acceleration provision");


and, in each case, the principal amount of any such Indebtedness, together with
the principal amount of any other such Indebtedness under which there has been a
Payment Default or the maturity of which has been so accelerated, aggregates $10
million or more;

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            (7)   (a)   the Parent or a Significant Subsidiary or a group of
                        Restricted Subsidiaries that, taken together (as of the
                        latest audited consolidated financial statements for the
                        Parent and its Restricted Subsidiaries), would
                        constitute a Significant Subsidiary pursuant to or
                        within the meaning of any Bankruptcy Law:

                        (1)   commences a voluntary case or proceeding;

                        (2)   consents to the entry of judgment, decree or order
                              for relief against it in an involuntary case or
                              proceeding;

                        (3)   consents to the appointment of a custodian of it
                              or for any substantial part of its property;

                        (4)   makes a general assignment for the benefit of its
                              creditors; or

                        (5)   consents to or acquiesces in the institution of a
                              bankruptcy or an insolvency proceeding against it;

                  or takes any comparable action under any foreign laws relating
                  to insolvency; or

                  (b)   a court of competent jurisdiction enters an order or
                        decree under any Bankruptcy Law that:

                        (1)   is for relief against the Parent or any
                              Significant Subsidiary or a group of Restricted
                              Subsidiaries that, taken together (as of the
                              latest audited consolidated financial statements
                              for the Parent and its Restricted Subsidiaries),
                              would constitute a Significant Subsidiary in an
                              involuntary case;

                        (2)   appoints a Custodian of the Parent or any
                              Significant Subsidiary or a group of Restricted
                              Subsidiaries that, taken together (as of the
                              latest audited consolidated financial statements
                              for the Parent and its Restricted Subsidiaries),
                              would constitute a Significant Subsidiary or for
                              any substantial part of its property; or

                        (3)   orders the winding up or liquidation of the Parent
                              or any Significant Subsidiary or a group of
                              Restricted Subsidiaries that, taken together (as
                              of the latest audited consolidated financial
                              statements for the Parent and its Restricted
                              Subsidiaries) would constitute a Significant
                              Subsidiary;

                  or any similar relief is granted under any foreign laws and
                  the order, decree or relief remains unstayed and in effect for
                  60 days;



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            (8)   failure by the Parent or any Significant Subsidiary or group
                  of Restricted Subsidiaries that, taken together (as of the
                  latest audited consolidated financial statements for the
                  Parent and its Restricted Subsidiaries), would constitute a
                  Significant Subsidiary to pay final judgments aggregating in
                  excess of $10 million (net of any amounts that a reputable and
                  creditworthy insurance company has acknowledged liability for
                  in writing), which judgments are not paid, discharged or
                  stayed for a period of 60 days.

            However, a default under clauses (4) and (5) of this Section 501
            will not constitute an Event of Default until the Trustee or the
            Holders of 25% in principal amount of Notes (voting together as a
            single class) comprising the outstanding Units notify the Parent and
            the Subsidiary Issuer of the default and the Parent and the
            Subsidiary Issuer do not cure such default within the time specified
            in clauses (4) and (5) of this Section 501 paragraph after receipt
            of such notice.

            Section 502 Acceleration of Maturity; Rescission and Annulment

            If an Event of Default (other than an Event of Default described in
      clause (7) of Section 501) occurs and is continuing, the Trustee by notice
      to the Parent and the Subsidiary Issuer, or the Holders of at least 25% in
      principal amount of the Notes (voting together as a single class)
      comprising the outstanding Units by notice to the Parent, the Subsidiary
      Issuer and the Trustee, may, and the Trustee at the request of such
      Holders shall, declare the principal of, premium, if any, and accrued and
      unpaid interest, if any, on all the Notes to be due and payable. Upon such
      a declaration, such principal, premium and accrued and unpaid interest
      will be due and payable immediately. In the event of a declaration of
      acceleration of the Units because an Event of Default described in clause
      (6) of Section 501 has occurred and is continuing, the declaration of
      acceleration of the Units shall be automatically annulled if the event of
      default or Payment Default triggering such Event of Default pursuant to
      clause (6) of Section 501 shall be remedied or cured by the Parent or a
      Restricted Subsidiary of the Parent or waived by the Holders of the
      relevant Indebtedness within 20 days after the declaration of acceleration
      with respect thereto and if (1) the annulment of the acceleration of the
      Units would not conflict with any judgment or decree of a court of
      competent jurisdiction and (2) all existing Events of Default, except
      nonpayment of principal, premium or interest on the Notes that became due
      solely because of the acceleration of the Notes, have been cured or
      waived. If an Event of Default described in clause (7) of Section 501
      above occurs and is continuing, the principal of, premium, if any, and
      accrued and unpaid interest on all the Notes will become and be
      immediately due and payable without any declaration or other act on the
      part of the Trustee or any Holders. The Holders of a majority in principal
      amount of Notes (voting together as a single class) comprising the
      outstanding Units may waive all past defaults (except with respect to
      nonpayment of principal, premium or interest) and rescind any such
      acceleration with respect to the Units and its consequences if (1)
      rescission would not conflict with any judgment or decree of a court of
      competent jurisdiction and (2) all existing Events of Default, other than
      the nonpayment of


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      the principal of, premium, if any, and interest on the Notes that have
      become due solely by such declaration of acceleration, have been cured or
      waived.

            Section 503 Other Remedies

            If an Event of Default occurs and is continuing, the Trustee may
      pursue any available remedy to collect the payment of principal of (or
      premium, if any) or interest on the Notes or to enforce the performance of
      any provision of the Units or this Indenture.

            The Trustee may maintain a proceeding even if it does not possess
      any of the Units or does not produce any of them in the proceeding. A
      delay or omission by the Trustee or any Holder in exercising any right or
      remedy accruing upon an Event of Default shall not impair the right or
      remedy or constitute a waiver of or acquiescence in the Event of Default.
      No remedy is exclusive of any other remedy. All available remedies are
      cumulative.

            Section 504 Waiver of Past Defaults

            The Holders of a majority in principal amount of the outstanding
      Notes and Units by notice to the Trustee may (a) waive, by their consent
      (including, without limitation consents obtained in connection with a
      purchase of, or tender offer or exchange offer for, Units), an existing
      Default or Event of Default and its consequences except (i) a Default or
      Event of Default in the payment of the principal of, or premium, if any,
      or interest on a Note or (ii) a Default or Event of Default in respect of
      a provision that under Section 901 cannot be amended without the consent
      of each Holder affected and (b) rescind any such acceleration with respect
      to the Notes and its consequences if (1) rescission would not conflict
      with any judgment or decree of a court of competent jurisdiction and (2)
      all existing Events of Default, other than the nonpayment of the principal
      of, premium, if any, and interest on the Notes that have become due solely
      by such declaration of acceleration, have been cured or waived. When a
      Default or Event of Default is waived, it is deemed cured, but no such
      waiver shall extend to any subsequent or other Default or Event of Default
      or impair any consequent right.

            Section 505 Control by Majority

            The Holders of a majority in principal amount of the outstanding
      Notes and Units may direct the time, method and place of conducting any
      proceeding for any remedy available to the Trustee or of exercising any
      trust or power conferred on the Trustee. However, the Trustee may refuse
      to follow any direction that conflicts with law or this Indenture or,
      subject to Section 601 and Section 602, that the Trustee determines is
      unduly prejudicial to the rights of other Holders or would involve the
      Trustee in personal liability; provided, however, that the Trustee may
      take any other action deemed proper by the Trustee that is not
      inconsistent with such direction. Prior to taking any action hereunder,
      the Trustee


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      shall be entitled to indemnification satisfactory to it in its sole
      discretion against all fees, losses and expenses caused by taking or not
      taking such action.

            Section 506 Limitation on Suits

            Subject to Section 504, a Holder may not pursue any remedy with
      respect to this Indenture or the Notes or the Units unless:

            (1)   such Holder has previously given the Trustee written notice
                  stating that an Event of Default is continuing;

            (2)   the Holders of at least 25% in principal amount of the Notes
                  (voting together as a single class) comprising the outstanding
                  Notes and Units have requested the Trustee to pursue the
                  remedy;

            (3)   such Holders have offered the Trustee reasonable security or
                  indemnity against any loss, liability, fees and expense;

            (4)   the Trustee has not complied with the request within 60 days
                  after receipt of the request and the offer of security or
                  indemnity; and

            (5)   the Holders of a majority in principal amount of the
                  outstanding Notes and Units have not given the Trustee a
                  direction that, in the opinion of the Trustee, is inconsistent
                  with such request during such 60-day period.

            A Holder may not use this Indenture to prejudice the rights of
      another Holder or to obtain a preference or priority over another Holder.

            Section 507 Rights of Holders to Receive Payment

            Notwithstanding any other provision of this Indenture (including,
      without limitation, Section 506), the right of any Holder to receive
      payment of principal of, premium (if any) or interest on the Notes held by
      such Holder, on or after the respective due dates expressed in the Notes,
      or to bring suit for the enforcement of any such payment on or after such
      respective dates, shall not be impaired or affected without the consent of
      such Notes.

            Section 508 Collection Suit by Trustee

            If an Event of Default specified in Section 501(1) or Section 501(2)
      occurs and is continuing, the Trustee may recover judgment in its own name
      and as trustee of an express trust against the Parent and the Subsidiary
      Issuer for the whole amount then due and owing (together with interest on
      any unpaid interest to the extent lawful) and the amounts provided for in
      Section 607.

            Section 509 Trustee May File Proofs of Claim



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            The Trustee may file such proofs of claim and other papers or
      documents as may be necessary or advisable in order to have the claims of
      the Trustee (including any claim for the reasonable compensation,
      expenses, disbursements and advances of the Trustee, its agents and
      counsel) and the Holders allowed in any judicial proceedings relative to
      the Parent or the Subsidiary Issuer or its or their respective creditors
      or properties and, unless prohibited by law or applicable regulations, may
      be entitled and empowered to participate as a member of any official
      committee of creditors appointed in such matter and, may vote on behalf of
      the Holders in any election of a trustee in bankruptcy or other Person
      performing similar functions, and any custodian in any such judicial
      proceeding is hereby authorized by each holder to make payments to the
      Trustee and, in the event that the Trustee shall consent to the making of
      such payments directly to the Holders, to pay to the Trustee any amount
      due it for the reasonable compensation, expenses, disbursements and
      advances of the Trustee, its agents and its counsel, and any other amounts
      due the Trustee under Section 607.

            Section 510 Priorities

            If the Trustee collects any money or property pursuant to this
      Article Five, it shall pay out the money or property in the following
      order:

            FIRST: to the Trustee for amounts due under Section 607;


            SECOND: subject to Article Twelve and Thirteen to Holders for
      amounts due and unpaid on the Notes for principal, premium, if any, and
      interest, ratably, without preference or priority of any kind, according
      to the amounts due and payable on the Notes for principal and interest,
      respectively; and

            THIRD: to the Parent or the Subsidiary Issuer, as the case may be.

            The Trustee may fix a record date and payment date for any payment
      to Holders pursuant to this Section. At least 15 days before such record
      date, the Trustee shall mail to each Holder and to the Parent and the
      Subsidiary Issuer a notice that states the record date, the payment date
      and amount to be paid.

            Section 511 Undertaking for Costs

            In any suit for the enforcement of any right or remedy under this
      Indenture or in any suit against the Trustee for any action taken or
      omitted by it as Trustee, a court in its discretion may require the filing
      by any party litigant in the suit of an undertaking to pay the costs of
      the suit, and the court in its discretion may assess reasonable costs,
      including reasonable attorneys' fees, against any party litigant in the
      suit, having due regard to the merits and good faith of the claims or
      defenses made by the party litigant. This Section does not apply to a suit
      by the Trustee, a suit by the Parent and the Subsidiary Issuer, a suit by
      a Holder pursuant to Section 507 or a suit by Holders of more than 10% in
      outstanding principal amount of the Notes and Units.



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            Section 512 Trustee May Enforce Claims Without Possession of Notes
      or Units.

            All rights of action and claims under this Indenture, the Notes or
      the Units may be prosecuted and enforced by the Trustee without the
      possession of any of the Notes or the Units or the production thereof in
      any proceeding relating thereto, and any such proceeding instituted by the
      Trustee shall be brought in its own name as trustee of an express trust,
      and any recovery of judgment shall, after provision for the payment of the
      compensation, expenses, disbursements and advances of the Trustee, its
      agents and counsel, be for the ratable benefit of the Holders of the Units
      in respect of which such judgment has been recovered."

      SECTION 2.7. TRUSTEE

            Article Six of each of the Original Indentures is supplemented,
amended and restated to read in its entirety as follows:

                                  "Article Six

                                   The Trustee

            Section 601 Duties of Trustee

            (a) If an Event of Default has occurred and is continuing, the
      Trustee shall exercise the rights and powers vested in it by this
      Indenture and use the same degree of care and skill in their exercise as a
      prudent Person would exercise or use under the circumstances in the
      conduct of such Person's own affairs; provided that if an Event of Default
      occurs and is continuing, the Trustee will be under no obligation to
      exercise the rights or powers under this Indenture at the request or
      direction of any of the Holders unless such Holders have offered to the
      Trustee indemnity or security against loss, liability or expense
      satisfactory to the Trustee in its sole discretion.

            (b) Except during the continuance of an Event of Default:

                  (i)   the Trustee undertakes to perform such duties and only
                        such duties as are specifically set forth in this
                        Indenture and no implied covenants or obligations shall
                        be read into this Indenture against the Trustee; and

                  (ii)  in the absence of bad faith on its part, the Trustee may
                        conclusively rely, as to the truth of the statements and
                        the correctness of the opinions expressed therein, upon
                        certificates, opinions or orders furnished to the
                        Trustee and conforming to the requirements of this
                        Indenture. However, in the case of any such certificates
                        or opinions which by any provisions hereof are
                        specifically required to be furnished to the Trustee,
                        the Trustee shall examine such certificates and opinions
                        to determine whether or not they


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                        conform on their face to the requirements of this
                        Indenture (but need not confirm or investigate the
                        accuracy of mathematical calculations or other facts
                        stated therein).

            (c) (1) The Trustee may not be relieved from liability for its own
      negligent action, its own negligent failure to act or its own willful
      misconduct, except that:

                        (A)   this paragraph does not limit the effect of
                              paragraph (b) of this Section 601;


                        (B)   the Trustee shall not be liable for any error of
                              judgment made in good faith by a Trust Officer
                              unless it is proved that the Trustee was negligent
                              in ascertaining the pertinent facts; and

                        (C)   the Trustee shall not be liable with respect to
                              any action it takes or omits to take in good faith
                              in accordance with a direction received by it
                              pursuant to Section 505.

                  (2)   Every provision of this Indenture that in any way
                        relates to the Trustee is subject to paragraphs (a), (b)
                        and (c) of this Section 601.

                  (3)   The Trustee shall not be liable for interest on any
                        money received by it except as the Trustee may agree in
                        writing with the Parent and the Subsidiary Issuer.

                  (4)   Money held in trust by the Trustee need not be
                        segregated from other funds except to the extent
                        required by law.

                  (5)   No provision of this Indenture shall require the Trustee
                        to expend or risk its own funds or otherwise incur
                        financial liability in the performance of any of its
                        duties hereunder or in the exercise of any of its rights
                        or powers, if it shall have reasonable grounds to
                        believe that repayment of such funds or adequate
                        indemnity against such risk or liability is not
                        reasonably assured to it.

                  (6)   Every provision of this Indenture relating to the
                        conduct or affecting the liability of or affording
                        protection to the Trustee shall be subject to the
                        provisions of this Section 601 and to the provisions of
                        the TIA.

                  (7)   Unless otherwise specifically provided in this
                        Indenture, any demand, request, direction or notice from
                        the Parent or the Subsidiary Issuer shall be sufficient
                        if signed by an


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                        Officer of either the Parent or the Subsidiary Issuer,
                        as the case may be.

                  (8)   The Trustee shall be under no obligation to exercise any
                        of the rights or powers vested in it by this Indenture
                        at the request or direction of any of the Holders unless
                        such Holders shall have offered to the Trustee
                        reasonable security or indemnity satisfactory to it
                        against the fees, costs, expenses (including reasonable
                        attorneys' fees and expenses) and liabilities that might
                        be incurred by it in compliance with such request or
                        direction.

            Section 602 Rights of Trustee

            Subject to Section 601:


            (1) The Trustee may conclusively rely on any document (whether in
      its original or facsimile form) reasonably believed by it to be genuine
      and to have been signed or presented by the proper person. The Trustee
      need not investigate any fact or matter stated in the document.

            (2) Before the Trustee acts or refrains from acting, it may require
      an Officers' Certificate and/or an Opinion of Counsel. The Trustee shall
      not be liable for any action it takes or omits to take in good faith in
      reliance on an Officers' Certificate or Opinion of Counsel.

            (3) The Trustee may act through its attorneys and agents and shall
      not be responsible for the misconduct or negligence of any agent appointed
      with due care.

            (4) The Trustee shall not be liable for any action it takes or omits
      to take in good faith which it believes to be authorized or within its
      rights or powers, unless the Trustee's conduct constitutes willful
      misconduct or negligence.

            (5) The Trustee may consult with counsel of its selection, and the
      advice or opinion of counsel with respect to legal matters relating to
      this Indenture, the Notes and the Units shall be full and complete
      authorization and protection from liability in respect of any action
      taken, omitted or suffered by it hereunder in good faith and in accordance
      with the advice or opinion of such counsel.

            (6) The Trustee is not required to make any inquiry or investigation
      into facts or matters stated in any document but the Trustee, in its
      discretion, may make such further inquiry or investigation into such facts
      or matters as it may see fit and, if the Trustee determines to make such
      further inquiry or investigation, it shall be entitled to examine the
      books, records and premises of the Parent and the Subsidiary Issuer.



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<PAGE>
                  (7) The Trustee is not required to take notice or shall not be
         deemed to have notice of any Default or Event of Default hereunder,
         unless a Trust Officer of the Trustee has actual knowledge thereof or
         has received notice in writing of such Default or Event of Default from
         the Parent or the Subsidiary Issuer or the Holders of at least 25% in
         aggregate principal amount of the Notes comprising the Units then
         outstanding, and in the absence of any such notice, the Trustee may
         conclusively assume that no such Default or Event of Default exists.

                  (8) The Trustee is not required to give any bond or surety
         with respect to the performance of its duties or the exercise of its
         powers under this Indenture.

                  (9) In the event the Trustee receives inconsistent or
         conflicting requests and indemnity from two or more groups of Holders
         of Units, each representing less than the aggregate principal amount of
         Notes outstanding required to take any action thereunder, the Trustee,
         in its sole discretion may determine what action, if any, shall be
         taken.

                  (10) The Trustee's immunities and protections from liability
         and its right to indemnification in connection with the performance of
         its duties under this Indenture shall extend to the Trustee's officers,
         directors, agents, attorneys and employees. Such immunities and
         protections and right to indemnification, together with the Trustee's
         right to compensation, shall survive the Trustee's resignation or
         removal, the discharge of this Indenture and final payments of the
         Units.

                  (11) The permissive right of the Trustee to take actions
         permitted by this Indenture shall not be construed as an obligation or
         duty to do so.

                  Section 603  Individual Rights of Trustee

                  The Trustee in its individual or any other capacity may become
         the owner or pledgee of the Notes and Units and may otherwise deal with
         the Parent, the Subsidiary Issuer or its respective Affiliates with the
         same rights it would have if it were not Trustee. Any Paying Agent,
         Registrar, co-registrar or co-paying agent may do the same with like
         rights. However, the Trustee must comply with Sections 610 and Section
         611.

                  Section 604  Trustee's Disclaimer

                  The Trustee shall not be responsible for and makes no
         representation as to the validity or adequacy of this Indenture, the
         Notes or the Units, it shall not be accountable for the Parent's and
         the Subsidiary Issuer's use of the proceeds from the issuance of the
         Notes and Units, and it shall not be responsible for any statement of
         the Parent and the Subsidiary Issuer in this Indenture or in any
         document issued in connection with the sale of the Notes and Units or
         in the Notes or Units other than the Trustee's certificate of
         authentication.

                  Section 605  Notice of Defaults


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                  If a Default or Event of Default occurs and is continuing and
         if a Trust Officer has actual knowledge thereof, the Trustee shall mail
         to each Holder notice of the Default or Event of Default within 30 days
         after the Trustee has knowledge of such default. Except in the case of
         a Default or Event of Default in payment of principal of, premium (if
         any), or interest on any Note or Unit (including payments pursuant to
         the optional redemption or required repurchase provisions of such Note,
         if any), the Trustee may withhold the notice if and so long a committee
         of its Trust Officers in good faith determines that withholding the
         notice is in the interests of Holders.

                  Section 606  Reports by Trustee to Holders

                  As promptly as practicable after each May 15, beginning with
         the May 15, following the date of this Indenture, and for so long as
         the Notes and Units remain outstanding, the Trustee shall mail to each
         Holder a brief report dated as of such reporting date that complies
         with TIA Section 313(a). The Trustee also shall comply with TIA Section
         313(b). The Trustee shall also transmit by mail all reports required by
         TIA Section 313(c).

                  A copy of each report at the time of its mailing to Holders
shall be filed with the SEC and each stock exchange (if any) on which the Notes
and the Units are listed. The Parent and the Subsidiary Issuer agree to notify
promptly the Trustee whenever the Notes and the Units become listed on any stock
exchange and of any delisting thereof.

                  Section 607  Compensation and Indemnity

                  Each of the Parent and the Subsidiary Issuer shall pay to the
         Trustee from time to time reasonable compensation for its acceptance of
         this Indenture and services hereunder as each of the Parent and the
         Subsidiary Issuer and the Trustee shall from time to time agree in
         writing. The Trustee's compensation shall not be limited by any law on
         compensation of a trustee of an express trust. The Parent and the
         Subsidiary Issuer shall reimburse the Trustee upon request for all
         reasonable out-of-pocket expenses incurred or made by it, including
         costs of collection, costs of preparing and reviewing reports,
         certificates and other documents, costs of preparation and mailing of
         notices to Holders, in addition to the compensation for its services.
         Such expenses shall include the reasonable compensation and expenses,
         disbursements and advances of the Trustee's agents, counsel,
         accountants and experts. Each of the Parent and the Subsidiary Issuer
         shall indemnify the Trustee against any and all loss, liability,
         damages, claims or expense (including reasonable attorneys' fees and
         expenses) incurred by it without negligence or willful misconduct on
         its part in connection with the administration of this trust and the
         performance of its duties hereunder, including the costs and expenses
         of enforcing this Indenture (including this Section 607) and of
         defending itself against any claims (whether asserted by any Holder,
         the Parent, the Subsidiary Issuer or otherwise). The Trustee shall
         notify the Parent and the Subsidiary Issuer promptly of any claim for
         which it may seek

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         indemnity. Failure by the Trustee to so notify the Parent and the
         Subsidiary Issuer shall not relieve the Parent and the Subsidiary
         Issuer of their obligations hereunder. The Parent and the Subsidiary
         Issuer shall defend the claim and the Trustee shall provide reasonable
         cooperation at the Parent and the Subsidiary Issuer's expense in the
         defense. The Trustee may have separate counsel and the Parent and the
         Subsidiary Issuer shall pay the fees and expenses of such counsel
         provided that the Parent and the Subsidiary Issuer shall not be
         required to pay such fees and expenses if it assumes the Trustee's
         defense, and, in the reasonable judgment of outside counsel to the
         Trustee, there is no conflict of interest between the Parent and the
         Subsidiary Issuer and the Trustee in connection with such defense. The
         Parent and the Subsidiary Issuer shall not be under any obligation to
         pay for any written settlement without its consent, which consent shall
         not be unreasonably delayed, conditioned or withheld. The Parent and
         the Subsidiary Issuer need not reimburse any expense or indemnify
         against any loss, liability or expense incurred by the Trustee through
         the Trustee's own willful misconduct or negligence.

                  To secure the Parent and the Subsidiary Issuer's payment
         obligations in this Section 607, the Trustee shall have a Lien prior to
         the Parent Notes or the Subsidiary Notes, as the case may be, on all
         money or property held or collected by the Trustee other than money or
         property held in trust to pay principal of and interest on the Parent
         Notes or the Subsidiary Notes, as the case may be.

                  The Parent and the Subsidiary Issuer's payment obligations
         pursuant to this Section 607 shall survive the discharge of this
         Indenture. When the Trustee incurs expenses after the occurrence of a
         Default specified in clause (7) of Section 501 with respect to the
         Parent, the expenses are intended to constitute expenses of
         administration under any Bankruptcy Law.

                  Section 608  Replacement of Trustee

                  The Trustee may resign at any time by so notifying the Parent
         and the Subsidiary Issuer. The Holders of a majority in principal
         amount of the Notes comprising the then outstanding Units may remove
         the Trustee by so notifying the Trustee and may appoint a successor
         Trustee. The Parent and the Subsidiary Issuer shall remove the Trustee
         if:

                  (1) the Trustee fails to comply with Section 610;

                  (2) the Trustee is adjudged bankrupt or insolvent;

                  (3) a receiver or other public officer takes charge of the
         Trustee or its property; or

                  (4) the Trustee otherwise becomes incapable of acting.

                  If the Trustee resigns or is removed by the Parent and the
         Subsidiary Issuer or by the Holders of a majority in principal amount
         of the then outstanding

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         Units and such Holders do not reasonably promptly appoint a successor
         Trustee, or if a vacancy exists in the office of the Trustee for any
         reason (the Trustee in such event being referred to herein as the
         retiring Trustee), the Parent and the Subsidiary Issuer shall promptly
         appoint a successor Trustee.

                  A successor Trustee shall deliver a written acceptance of its
         appointment to the retiring Trustee and to the Parent and the
         Subsidiary Issuer. Thereupon the resignation or removal of the retiring
         Trustee shall become effective, and the successor Trustee shall have
         all the rights, powers and duties of the Trustee under this Indenture.
         The successor Trustee shall mail a notice of its succession to Holders.
         The retiring Trustee shall promptly transfer all property held by it as
         Trustee to the successor Trustee, subject to the lien provided for in
         Section 607

                  If a successor Trustee does not take office within 60 days
         after the retiring Trustee resigns or is removed, the retiring Trustee
         or the Holders of at least 10% in principal amount of the then
         outstanding Units may petition, at the Parent and the Subsidiary
         Issuer's expense, any court of competent jurisdiction for the
         appointment of a successor Trustee.

                  If the Trustee fails to comply with Section 610, unless the
         Trustee's duty to resign is stayed as provided in TIA Section 310(b),
         any Holder who has been a bona fide Holder of a Unit for at least six
         months may petition any court of competent jurisdiction for the removal
         of the Trustee and the appointment of a successor Trustee.

                  Notwithstanding the replacement of the Trustee pursuant to
         this Section 608, the obligations of the Parent and the Subsidiary
         Issuer under Section 607 shall continue for the benefit of the retiring
         Trustee.

                  Section 609  Successor Trustee by Merger

                  If the Trustee consolidates with, merges or converts into, or
         transfers all or substantially all its corporate trust business or
         assets to, another corporation or banking association, the resulting,
         surviving or transferee corporation without any further act shall be
         the successor Trustee.

                  In case at the time such successor or successors by merger,
         conversion or consolidation to the Trustee shall succeed to the trusts
         created by this Indenture, any of the Notes and Units shall have been
         authenticated but not delivered, any such successor to the Trustee may
         adopt the certificate of authentication of any predecessor trustee, and
         deliver such Notes and Units so authenticated; and in case at that time
         any of the Notes and Units shall not have been authenticated, any
         successor to the Trustee may authenticate such Notes and Units either
         in the name of any predecessor hereunder or in the name of the
         successor to the Trustee; and in all such cases such certificates shall
         have the full force which it is anywhere in the Notes and Units or in
         this Indenture.

                  Section 610  Eligibility; Disqualification


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                  The Trustee shall at all times satisfy the requirements of TIA
         Section 310(a). The Trustee shall have a combined capital and surplus
         of at least $100 million as set forth in its most recent published
         annual report of condition. The Trustee shall comply with TIA Section
         310(b); provided, however, that there shall be excluded from the
         operation of TIA Section 310(b)(1) any indenture or indentures under
         which other securities or certificates of interest or participation in
         other securities of the Parent or the Subsidiary Issuer are outstanding
         if the requirements for such exclusion set forth in TIA Section
         310(b)(1) are met.

                  Section 611 Preferential Collection of Claims Against the
Parent or Subsidiary Issuer

                  The Trustee shall comply with TIA Section 311(a), excluding
         any creditor relationship listed in TIA Section 311(b). A Trustee who
         has resigned or been removed shall be subject to TIA Section 311(a) to
         the extent indicated."

         SECTION 2.8. DEFEASANCE AND COVENANT DEFEASANCE

         Article Fifteen of each of the Original Indentures is supplemented,
amended and restated to read in its entirety as follows:

                                "Article Fifteen

                       DEFEASANCE AND COVENANT DEFEASANCE

                  Section 1501  Discharge of Liability on Notes and Units;
Defeasance

                  (a) Subject to Section 1501(c), when (i)(x) the Parent or the
         Subsidiary Issuer delivers to the Trustee all outstanding Units (other
         than Units replaced pursuant to Section 1.6) for cancellation or (y)
         all outstanding Units not theretofore delivered for cancellation have
         become due and payable, whether at maturity or upon redemption or will
         become due and payable within one year or are to be called for
         redemption within one year under arrangements satisfactory to the
         Trustee for the giving of notice of redemption by the Trustee in the
         name and at the expense of the Parent or the Subsidiary Issuer and the
         irrevocably deposits or causes to be deposited with the Trustee as
         trust funds in trust solely for the benefit of the Holders money in
         U.S. dollars, non-callable U.S. Government Securities, or a combination
         thereof, in such amounts as will be sufficient without consideration of
         any reinvestment of interest to pay and discharge the entire
         indebtedness on such Units not theretofore delivered to the Trustee for
         cancellation for principal, premium, if any, and accrued interest to
         the date of maturity or redemption, (ii) no Default or Event of Default
         shall have occurred and be continuing on the date of such deposit or
         shall occur as a result of such deposit and such deposit will not
         result in a breach or violation of, or constitute a default under, any
         other instrument to which the Parent or the Subsidiary Issuer is a
         party or by which the Parent or the Subsidiary Issuer is bound; (iii)
         the Parent or the Subsidiary Issuer has paid or caused to be paid all
         sums payable by it under

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         this Indenture and the Units; and (iv) the Parent or the Subsidiary
         Issuer has delivered irrevocable instructions to the Trustee under this
         Indenture to apply the deposited money toward the payment of such Units
         at maturity or the Redemption Date, as the case may be, then the
         Trustee shall acknowledge satisfaction and discharge of this Indenture
         on demand of the Parent or the Subsidiary Issuer (accompanied by an
         Officers' Certificate and an Opinion of Counsel stating that all
         conditions precedent specified herein relating to the satisfaction and
         discharge of this Indenture have been complied with) and at the cost
         and expense of the Parent or the Subsidiary Issuer, as the case may be.

                  (b) Subject to Sections 1501(c) and 1502, the Parent or the
         Subsidiary Issuer at any time may terminate (i) all its obligations
         under the Units and this Indenture ("legal defeasance option"), and
         after giving effect to such legal defeasance, any omission to comply
         with such obligations shall no longer constitute a Default or Event of
         Default or (ii) its obligations under, Section 1004, Section 1005,
         Section 1006, Section 1007, Section 1008, Section 1009, Section 1010,
         Section 1011, Section 1012, Section 1013, Section 1014, Section 1015,
         Section 1017, clause (3) of Section 801 and Article Thirteen and the
         Parent or the Subsidiary Issuer may omit to comply with and shall have
         no liability in respect of any term, condition or limitation set forth
         in any such covenant, whether directly or indirectly, by reason of any
         reference elsewhere herein to any such covenant or by reason of any
         reference in any such covenant to any other provision herein or in any
         other document and such omission to comply with such covenants shall no
         longer constitute a Default or an Event of Default under Section 501(3)
         (solely as it relates to clause (3) of Section 801) and Section 501(4)
         and the operation of Sections 501(6), 501(7) (with respect only to
         Significant Subsidiaries) and 501(8) and the events specified in such
         Sections shall no longer constitute an Event of Default (clause (ii)
         being referred to as the "covenant defeasance option"), but except as
         specified above, the remainder of this Indenture and the Units shall be
         unaffected thereby. The Parent or the Subsidiary Issuer may exercise
         its legal defeasance option notwithstanding its prior exercise of its
         covenant defeasance option. If the Parent or the Subsidiary Issuer
         exercises its covenant defeasance option, the Parent or the Subsidiary
         Issuer may elect to have any Subsidiary Guarantees in effect at such
         time terminate.

                  If the Parent or the Subsidiary Issuer exercises its legal
         defeasance option, payment of the Units may not be accelerated because
         of an Event of Default, and the Parent Guarantees in effect at such
         time shall terminate. If the Parent exercises its covenant defeasance
         option, payment of the Units may not be accelerated because of an Event
         of Default specified in Section 501(3) (with respect only to the
         Parent's obligations under Article Thirteen), Section 501(4), Section
         501(5), Section 501(6), Section 501(7) (with respect only to
         Significant Subsidiaries) or Section 501(8) or the failure of the
         Parent to comply with clause (3) of Section 801.


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                  Upon satisfaction of the conditions set forth herein and upon
         request of the Parent or the Subsidiary Issuer, the Trustee shall
         acknowledge in writing the discharge of those obligations that the
         Parent or the Subsidiary Issuer terminates.

                  (c) Notwithstanding the provisions of Section 1501(a) and
         Section 1501(b), the obligations of the Parent and the Subsidiary
         Issuer in Section 1.2, Section 1.3, Section 2.4, Section 2.5, Section
         2.6, Section 2.7, Section 2.8, Section 2.9, Section 1001, Section 1002,
         Section 1003, Section 1016, Section 1018, Section 507, Section 607,
         Section 608, and in this Article Fifteen shall survive until the Notes
         and the Units have been paid in full. Thereafter, the obligations of
         the Parent and the Subsidiary Issuer in Section 607, Section 1504 and
         Section 1505 shall survive.

                  Section 1502  Conditions to Defeasance

                  The Parent or the Subsidiary Issuer may exercise its legal
         defeasance option or its covenant defeasance option only if:

                  (a) the Parent or the Subsidiary Issuer irrevocably deposits
         in trust with the Trustee for the benefit of the Holders money in U.S.
         dollars or U.S. Government Securities or a combination thereof for the
         payment of principal, premium, if any, and interest on the Units to
         maturity or redemption, as the case may be;

                  (b) the Parent or the Subsidiary Issuer delivers to the
         Trustee a certificate from a nationally recognized firm of independent
         accountants expressing their opinion that the payments of principal and
         interest when due and without reinvestment on the deposited U.S.
         Government Securities plus any deposited money without investment will
         provide cash at such times and in such amounts as will be sufficient to
         pay principal and interest when due on all the Units to maturity;

                  (c) no Default or Event of Default shall have occurred and be
         continuing on the date of such deposit or, with respect to certain
         bankruptcy or insolvency Events of Default, on the 91st day after such
         date of deposit;

                  (d) such legal defeasance or covenant defeasance shall not
         result in a breach or violation of, or constitute a Default under, this
         Indenture or any other material agreement or instrument to which the
         Parent or the Subsidiary Issuer, as the case may be, or any of its
         subsidiaries is a party or by which the Parent or the Subsidiary
         Issuer, as the case may be or any of its subsidiaries is bound;

                  (e) the Parent or the Subsidiary Issuer delivers to the
         Trustee an Opinion of Counsel (subject to customary assumptions and
         exclusions) to the effect that the trust resulting from the deposit
         does not constitute, or is qualified as, a regulated investment company
         under the Investment Company Act of 1940;


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<PAGE>
                  (f) in the case of the legal defeasance option, the Parent or
         the Subsidiary Issuer shall have delivered to the Trustee an Opinion of
         Counsel (subject to customary assumptions and exclusions) in the United
         States stating that (i) the Parent or the Subsidiary Issuer has
         received from, or there has been published by, the Internal Revenue
         Service a ruling, or (ii) since the date of this Indenture there has
         been a change in the applicable federal income tax law, in either case
         to the effect that, and based thereon such Opinion of Counsel shall
         confirm that, the Holders will not recognize income, gain or loss for
         federal income tax purposes as a result of such defeasance and will be
         subject to federal income tax on the same amounts, in the same manner
         and at the same times as would have been the case if such legal
         defeasance had not occurred;

                  (g) in the case of the covenant defeasance option, the Parent
         or the Subsidiary Issuer shall have delivered to the Trustee an Opinion
         of Counsel (subject to customary assumptions and exclusions) in the
         United States to the effect that the Holders will not recognize income,
         gain or loss for federal income tax purposes as a result of such
         deposit and covenant defeasance and will be subject to federal income
         tax on the same amount, in the same manner and at the same times as
         would have been the case if such deposit and covenant defeasance had
         not occurred; and

                  (h) the Parent or the Subsidiary Issuer delivers to the
         Trustee an Officers' Certificate and an Opinion of Counsel, each
         stating that all conditions precedent to the defeasance and discharge
         of the Notes and Units and this Indenture as contemplated by this
         Article Fifteen have been complied with.

                  Section 1503  Application of Trust Money

                  The Trustee shall hold in trust money or U.S. Government
         Securities deposited with it pursuant to this Article Fifteen. It shall
         apply the deposited money and the money from U.S. Government Securities
         through the Paying Agent and in accordance with this Indenture to the
         payment of principal of and interest on the Notes.

                  Section 1504  Repayment to Parent or Subsidiary Issuer

                  The Trustee and the Paying Agent shall promptly turn over to
         the Parent or the Subsidiary Issuer upon request any excess money or
         securities held by them upon payment of all the obligations under this
         Indenture.

                  Subject to any applicable abandoned property law, the Trustee
         and the Paying Agent shall pay to the Parent or the Subsidiary Issuer
         upon request any money held by them for the payment of principal of or
         interest on the Units that remains unclaimed for two years, and,
         thereafter, Holders entitled to the money must look to the Parent or
         the Subsidiary Issuer for payment as general creditors.

                  Section 1505  Indemnity for U.S. Government Securities


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                  The Parent or the Subsidiary Issuer shall pay and shall
         indemnify the Trustee against any tax, fee or other charge imposed on
         or assessed against deposited U.S. Government Securities or the
         principal and interest received on such U.S. Government Securities.

                  Section 1506  Reinstatement

                  If the Trustee or Paying Agent is unable to apply any money or
         U.S. Government Securities in accordance with this Article Fifteen by
         reason of any legal proceeding or by reason of any order or judgment of
         any court or governmental authority enjoining, restraining or otherwise
         prohibiting such application, the obligations of the Parent or the
         Subsidiary Issuer under this Indenture and the Units shall be revived
         and reinstated as though no deposit had occurred pursuant to this
         Article Fifteen until such time as the Trustee or Paying Agent is
         permitted to apply all such money or U.S. Government Securities in
         accordance with this Article Fifteen; provided, however, that, if the
         Parent or the Subsidiary Issuer has made any payment of interest on or
         principal of any Notes because of the reinstatement of its obligations,
         the Parent or the Subsidiary Issuer shall be subrogated to the rights
         of the Holders of such Units to receive such payment from the money or
         U.S. Government Securities held by the Trustee or Paying Agent.

                  The Trustee's rights under this Article Fifteen shall survive
         termination of this Indenture."

         SECTION 2.9. AMENDMENTS

         Article Nine of each of the Original Indentures is supplemented,
amended and restated to read in its entirety as follows:

                                  "Article Nine

                                   AMENDMENTS

                  Section 901 Supplemental Indentures Without Consent of Holders

                  The Parent and the Subsidiary Issuer, each when authorized by
         a Board Resolution and the Trustee, at any time and from time to time,
         may amend or supplement this Indenture, the Notes or the Units, without
         the consent of any of the Holders of the Units, for any of the
         following purposes:

                  (1)      cure any ambiguity, omission, defect or
                           inconsistency;

                  (2)      provide for the assumption by a successor
                           corporation, partnership, trust or limited liability
                           company of the obligations of the Parent or the
                           Subsidiary Issuer under this Indenture;


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                  (3)      provide for uncertificated Units in addition to or in
                           place of certificated Units (provided that the
                           uncertificated Units are issued in registered form
                           for purposes of Section 163(f) of the Code, or in a
                           manner such that the uncertificated Units are
                           described in Section 163(f)(2)(B) of the Code);

                  (4)      add Guarantees with respect to the Notes; provided,
                           however, that the designation is in accord with the
                           applicable provisions of this Indenture;

                  (5)      secure the Notes;

                  (6)      add to the covenants of the Parent or the Subsidiary
                           Issuer for the benefit of the Holders or surrender
                           any right or power conferred upon the Parent or the
                           Subsidiary Issuer;

                  (7)      make any change that does not adversely affect the
                           rights of any Holder;

                  (8)      comply with any requirement of the SEC in connection
                           with the qualification of this Indenture under the
                           Trust Indenture Act;

                  (9)      provide for the issuance of exchange securities which
                           shall have terms substantially identical in all
                           respects to the Units (except that the transfer
                           restrictions contained in the Units shall be modified
                           or eliminated as appropriate) and which shall be
                           treated, together with any outstanding Units, as a
                           single class of securities;

                  (9)      make any change in the subordination provisions of
                           this Indenture that would limit or terminate the
                           benefits available to any holder of Senior
                           Indebtedness of the Parent or the Subsidiary Issuer
                           (or any Representative thereof) under such
                           subordination provisions;

                  (10)     provide for the assumption by the Parent of the
                           obligations of Subsidiary Issuer under the Subsidiary
                           Notes and the related release of the Subsidiary of
                           the Subsidiary Issuer from its obligations
                           thereunder; or

                  (11)     provide for the release of the Parent Guarantee in
                           accordance with this Indenture.

                  Section 902  Supplemental Indentures With Consent of Holders

                  The Parent and the Subsidiary Issuer, each when authorized by
         a Board Resolution and the Trustee, at any time and from time to time,
         may amend or supplement this Indenture, the Notes or the Units with the
         consent of the Holders of at least a majority in principal amount of
         the Notes (voting together as a single class) comprising Units then
         outstanding (including, without limitation, consents

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<PAGE>
         obtained in connection with a purchase of, or tender offer or exchange
         offer for, Units) and, any past default or compliance with any
         provisions may be waived with the consent of the Holders of a majority
         in principal amount of the Notes (voting together as a single class)
         comprising Units then outstanding (including, without limitation,
         consents obtained in connection with a purchase of, or tender offer or
         exchange offer for, Units). In addition, any amendment to Article
         Twelve that adversely affects the rights of any Holder of the Parent
         Notes or the Subsidiary Notes will require the consent of at least
         66-2/3% in aggregate principal amount of the Parent Notes or Subsidiary
         Notes, respectively, then outstanding. However, without the consent of
         each Holder of an outstanding Unit affected, no amendment may, among
         other things:

                  (1)      reduce the principal amount of Notes comprising the
                           Units whose Holders must consent to an amendment;

                  (2)      reduce the stated rate of or extend the stated time
                           for payment of interest on any Note;

                  (3)      reduce the principal of or extend the Stated Maturity
                           of any Note;

                  (4)      reduce the premium payable upon the redemption or
                           repurchase of any Note or change the time at which
                           any Note may be redeemed or repurchased as described
                           above under Article Eleven, Section 1009 and Section
                           1017 or any similar provision, whether through an
                           amendment or waiver of provisions in the covenants,
                           definitions or otherwise;

                  (5)      make any Note payable in money other than that stated
                           in the Note;

                  (6)      impair the right of any Holder to receive payment of,
                           premium, if any, principal of and interest on such
                           Holder's Notes on or after the due dates therefor or
                           to institute suit for the enforcement of any payment
                           on or with respect to such Holder's Notes;

                  (7)      make any change in the amendment provisions which
                           require each Holder's consent or in the waiver
                           provisions;

                  (8)      make any change to the subordination provisions of
                           this Indenture that adversely affects the rights of
                           any Holder of Units.

                  It shall not be necessary for the consent of the Holders under
         this Section to approve the particular form of any proposed
         supplemental indenture, but it shall be sufficient if such consent
         shall approve the substance thereof.

                  After a supplemental indenture under this Section becomes
         effective, the Parent and the Subsidiary Issuer shall mail to Holders
         of Units a notice briefly describing such amendment. The failure to
         give such notice to all Holders of Units, or any defect therein, shall
         not impair the validity of a supplemental indenture under this section.


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                  Section 903  Execution of Supplemental Indentures

                  In executing, or accepting the additional trusts created by,
         any supplemental indenture permitted by this Article or the
         modifications thereby of the trusts created by this Indenture, the
         Trustee shall be entitled to receive, and shall be fully protected in
         relying upon, an Officer's Certificate and Opinion of Counsel from the
         Parent and the Subsidiary Issuer stating that the execution of such
         supplemental indenture is authorized or permitted by this Indenture.
         The Trustee may, but shall not be obligated to, enter into any such
         supplemental indenture which affects the Trustee's own rights, duties
         or immunities under this Indenture or otherwise.

                  Section 904  Effect of Supplemental Indentures

                  Upon the execution of any supplemental indenture under this
         Article, this Indenture shall be modified in accordance therewith, and
         such supplemental indenture shall form a part of this Indenture for all
         purposes; and every Holder of Units theretofore or thereafter
         authenticated and delivered hereunder shall be bound thereby.

                  Section 905  Conformity with Trust Indenture Act

                  Every amendment or supplement to this Indenture, the Notes or
         the Units executed pursuant to this Article shall comply with the
         requirements of the TIA as then in effect.

                  Section 906  Reference in Notes and Units to Supplemental
Indentures

                  Notes and Units authenticated and delivered after the
         execution of any supplemental indenture pursuant to this Article Nine
         may, and shall if required by the Trustee, bear a notation in form
         approved by the Trustee as to any matter provided for in such
         supplemental indenture. If the Parent or the Subsidiary Issuer shall so
         determine, new Notes and any Parent Guarantees endorsed thereon and new
         Units so modified as to conform, in the opinion of the Trustee, the
         Parent and the Subsidiary Issuer, to any such supplemental indenture
         may be prepared and executed by the Parent and the Subsidiary Issuer
         and such new Notes and Units may be authenticated and delivered by the
         Trustee in exchange for outstanding Notes and Units."

         SECTION 2.10. SUBORDINATION OF NOTES

         Article Twelve of each of the Original Indentures is hereby
supplemented, amended and restated to read in its entirety as follows:

                                 "Article Twelve

                             SUBORDINATION OF NOTES


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                  Section 1201  Notes Subordinate to Senior Indebtedness

                  The Parent covenants and agrees, and each Holder of a Parent
         Note, by accepting a Parent Note, likewise covenants and agrees, that,
         to the extent and in the manner hereinafter set forth in this Article,
         the payment of the principal of (and premium, if any) and interest on
         each and all of the Parent Notes is hereby expressly made subordinate
         in right of payment to the prior payment in full of all existing and
         future Senior Indebtedness of the Parent.

                  The Subsidiary Issuer covenants and agrees, and each Holder of
         a Subsidiary Note, by accepting a Subsidiary Note, likewise covenants
         and agrees, that, to the extent and in the manner hereinafter set forth
         in this Article, the payment of the principal of (and premium, if any)
         and interest on each and all of the Subsidiary Notes (and any
         Additional Amounts) is hereby expressly made subordinate in right of
         payment to the prior payment in full of all existing and future Senior
         Indebtedness of the Subsidiary Issuer.

                  Section 1202  Liquidation, Dissolution and Bankruptcy of
Parent and Subsidiary Issuer

                  (a) Upon any distribution to creditors of the Parent in a
         liquidation or dissolution of the Parent or in a bankruptcy,
         reorganization, insolvency, receivership or similar proceeding relating
         to the Parent or its property, an assignment for the benefit of
         creditors or any marshalling of the Parent's assets and liabilities:

                           (1)      holders of Senior Indebtedness of the Parent
                                    shall be entitled to receive payment in full
                                    in cash (or U.S. dollar-denominated Cash
                                    Equivalents) of such Senior Indebtedness
                                    (including interest after the commencement
                                    of any such proceeding at the rate specified
                                    in the applicable Senior Indebtedness)
                                    before the Holders of the Parent Notes shall
                                    be entitled to receive any payment of any
                                    kind or character with respect to the Parent
                                    Notes; and

                           (2)      until the Senior Indebtedness of the Parent
                                    is paid in full in cash (or U.S.
                                    dollar-denominated Cash Equivalents), any
                                    distribution to which the Holders of Parent
                                    Notes would be entitled but for this Article
                                    shall be made to the holders of the Senior
                                    Indebtedness of the Parent.

                  Notwithstanding the foregoing, Holders of Parent Notes may
         receive (i) securities that are subordinated at least to the same
         extent as the Parent Notes to Senior Indebtedness and any securities
         issued in exchange for Senior Indebtedness and (ii) payments made from
         the defeasance trusts described in Article Fifteen.


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                  (b) Upon any distribution to creditors of the Subsidiary
         Issuer in a liquidation or dissolution of the Subsidiary Issuer or in a
         bankruptcy, reorganization, insolvency, receivership or similar
         proceeding relating to the Subsidiary Issuer or its property, an
         assignment for the benefit of creditors or any marshalling of the
         Subsidiary Issuer's assets and liabilities:

                           (1)      holders of Senior Indebtedness of the
                                    Subsidiary Issuer shall be entitled to
                                    receive payment in full in cash (or U.S.
                                    dollar-denominated Cash Equivalents) of such
                                    Senior Indebtedness (including interest
                                    after the commencement of any such
                                    proceeding at the rate specified in the
                                    applicable Senior Indebtedness) before the
                                    Holders of Subsidiary Notes shall be
                                    entitled to receive any payment of any kind
                                    or character with respect to the Subsidiary
                                    Notes; and

                           (2)      until the Senior Indebtedness of the
                                    Subsidiary Issuer is paid in full in cash
                                    (or U.S. dollar-denominated Cash
                                    Equivalents), any distribution to which the
                                    Holders of Subsidiary Notes would be
                                    entitled but for this Article shall be made
                                    to the holders of the Senior Indebtedness of
                                    the Subsidiary Issuer.

                  Notwithstanding the foregoing, Holders of Subsidiary Notes may
         receive (i) securities that are subordinated at least to the same
         extent as the Subsidiary Notes to Senior Indebtedness of the Subsidiary
         Issuer and any securities issued in exchange for Senior Indebtedness of
         the Subsidiary Issuer and (ii) payments made from the trusts described
         in Article Fifteen.

                  Section 1203  Suspension of Payment When Senior Indebtedness
in Default

                  (a) The Parent and the Subsidiary Issuer may not pay principal
         of, premium if any, or interest on, or other payment obligations in
         respect of, the Notes or make any deposit pursuant to the provisions
         described under Article Fifteen and may not otherwise purchase, redeem
         or retire any Notes or Units (collectively, "pay the Notes") if: (1)
         any Senior Indebtedness is not paid when due in cash or Cash
         Equivalents or (2) any other default or Senior Indebtedness occurs and
         the maturity of such Senior Indebtedness is accelerated in accordance
         with its terms unless, in either case, the default has been cured or
         waived and any such acceleration has been rescinded or such Senior
         Indebtedness has been paid in full in cash or Cash Equivalents.

                  However, the Parent and the Subsidiary Issuer may pay the
         Notes if the Parent and the Trustee receive written notice approving
         such payment from the Representative of the Senior Indebtedness with
         respect to which either of the events set forth in clause (1) or (2) of
         the immediately preceding sentence has occurred and is continuing.


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                  (b) The Parent and the Subsidiary Issuer also will not be
         permitted to pay the Notes for a Payment Blockage Period (as defined
         below) during the continuance of any default (a "Non-Payment Default"),
         other than a Payment Default described in Section 1203(a) hereof, on
         any Designated Senior Indebtedness that permits the holders of the
         Designated Senior Indebtedness to accelerate its maturity immediately
         without either further notice (except such notice as may be required to
         effect such acceleration) or the expiration of any application grace
         periods. A "Payment Blockage Period" commences on the receipt by the
         Trustee (with a copy to the Parent) of written notice (a "Blockage
         Notice") of a default of the kind described in the immediately
         preceding sentence from the Representative of the holders of such
         Designated Senior Indebtedness specifying an election to effect a
         Payment Blockage Period and ends on the earliest of (a) 179 days
         thereafter, (b) the date on which such Non-Payment Default is cured,
         waived in writing or ceases to exist, (c) the date on which such
         Designated Senior Indebtedness is repaid in full or (d) the date on
         which such Payment Blockage Period will have been terminated by written
         notice to the Trustee and the Parent from the Person or Persons who
         gave such Blockage Notice.

                  The Parent and the Subsidiary Issuer may resume payments on
         the Notes after the end of the Payment Blockage Period (including any
         missed payments), unless the holders of such Designated Senior
         Indebtedness or the Representative of such holders have accelerated the
         maturity of such Designated Senior Indebtedness. Not more than one
         Blockage Notice may be given in any consecutive 360-day period,
         irrespective of the number of defaults with respect to Designated
         Senior Indebtedness during such period. In no event, however, may the
         total number of days during which any Payment Blockage Period or
         Periods is in effect exceed 179 days in the aggregate during any 360
         consecutive day period. For purposes of this paragraph, no default or
         event of default that existed or was continuing on the date of the
         commencement of any Payment Blockage Period with respect to the
         Designated Senior Indebtedness initiating such Payment Blockage Period
         shall be, or be made, the basis of the commencement of a subsequent
         Payment Blockage Period by the Representative of such Designated Senior
         Indebtedness, whether or not within a period of 360 consecutive days,
         unless such default or event of default shall have been cured or waived
         for a period of not less than 90 consecutive days.

                  (c) If payment of the Notes is accelerated because of an Event
         of Default, the Parent or the Trustee will promptly notify the holders
         of the Designated Senior Indebtedness or the Representatives of such
         holders of the acceleration. The Parent and the Subsidiary Issuer may
         not pay the Notes until five Business Days after such acceleration and,
         after that five Business Day period, may pay the Notes only if the
         subordination provisions of this Indenture otherwise permit payment at
         that time.

                  (d) In the event that, notwithstanding the foregoing, the
         Parent or the Subsidiary Issuer will make any payment to the Trustee or
         the Holder of any Note

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         prohibited by the foregoing provisions of this Section, then and in
         such event such payment will be paid over and delivered forthwith to
         the Parent or the Subsidiary Issuer, as the case may be. In the event
         that the Parent or the Subsidiary Issuer will make any payment in
         respect of the Notes to the Trustee and the Trustee will receive
         written notice of a Payment Default or a Non-payment Default from one
         or more of the holders of Designated Senior Indebtedness (or their
         representative) prior to making any payment to Holders in respect of
         the Notes and prior to 11:00 a.m. Eastern Time, on the date which is
         two Business Days prior to the date upon which by the terms hereof any
         money may become payable for any purpose, such payments will be paid
         over by the Trustee and delivered forthwith to the Parent or the
         Subsidiary Issuer, as the case may be.

                  Section 1204  Subrogation to Rights of Holders of Senior
Indebtedness

                  (a) After all Senior Indebtedness of the Parent is irrevocably
         paid in full in cash or U.S. dollar-denominated Cash Equivalents
         reasonably satisfactory to the holders thereof and until the Parent
         Notes are paid in full, Holders of Parent Notes shall be subrogated
         (equally and ratably with all other Indebtedness pari passu with the
         Parent Notes) to the rights of holders of Senior Indebtedness of the
         Parent to receive distributions applicable to such Senior Indebtedness.
         A distribution made under this Article to holders of Senior
         Indebtedness of the Parent that otherwise would have been made to
         Holders of the Parent Notes is not, as between the Parent and the
         Holders of Parent Notes, a payment by the Parent on the Senior
         Indebtedness of the Parent.

                  (b) After all Senior Indebtedness of the Subsidiary Issuer is
         irrevocably paid in full in cash or U.S. dollar-denominated Cash
         Equivalents reasonably satisfactory to the holders thereof and until
         the Subsidiary Notes are paid in full, Holders of Subsidiary Notes
         shall be subrogated (equally and ratably with all other Indebtedness
         pari passu with the Subsidiary Notes) to the rights of holders of
         Senior Indebtedness of the Subsidiary Issuer to receive distributions
         applicable to such Senior Indebtedness. A distribution made under this
         Article to holders of Senior Indebtedness of the Subsidiary Issuer that
         otherwise would have been made to Holders of the Subsidiary Notes is
         not, as between the Parent and the Holders of Subsidiary Notes, a
         payment by the Subsidiary Issuer on the Senior Indebtedness of the
         Subsidiary Issuer.

                  Section 1205  Provisions Solely to Define Relative Rights

                  This Article defines the relative rights of Holders of Notes
         and Units and holders of Senior Indebtedness. Nothing in this Indenture
         shall:

                  (1)      impair, as between the Parent and Holders of Parent
                           Notes and between the Subsidiary Issuer and Holders
                           of Subsidiary Notes, the obligation of the Parent and
                           the Subsidiary Issuer, which is absolute and
                           unconditional, to pay principal of and interest on
                           the

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                           Parent Notes and the Subsidiary Notes, as the case
                           may be, in accordance with their respective terms;

                  (2)      affect the relative rights of Holders of Notes and
                           Units and other creditors of the Parent or the
                           Subsidiary Issuer, as the case may be, other than
                           their rights in relation to holders of Senior
                           Indebtedness; or

                  (3)      prevent the Trustee or any Holder of Notes or Units
                           from exercising its available remedies upon a Default
                           or Event of Default, subject to the rights of holders
                           and owners of Senior Indebtedness to receive
                           distributions and payments otherwise payable to
                           Holders of Parent Notes or Subsidiary Notes.

                  If the Parent of the Subsidiary Issuer fails because of this
         Article to pay principal of or interest on a Notes on the due date, the
         failure is still a Default or Event of Default.

                  Section 1206  Trustee to Effectuate Subordination

                  Each Holder of a Parent Note and a Subsidiary Issuer Note by
         his acceptance thereof authorizes and directs the Trustee on his behalf
         to take such action as may be necessary or appropriate to effectuate
         the subordination provided in this Article and appoints the Trustee his
         attorney-in-fact for any and all such purposes.

                  Section 1207  No Waiver of Subordination Provisions

                  (a) No right of any present or future holder of any Senior
         Indebtedness of the Parent or the Subsidiary Issuer to enforce
         subordination as herein provided shall at any time in any way be
         prejudiced or impaired by any act or failure to act on the part of the
         Parent or the Subsidiary Issuer, as the case may be, or by any act or
         failure to act, in good faith, by any such holder, or by any
         noncompliance by the Parent or the Subsidiary Issuer with the terms,
         provisions and covenants of this Indenture, regardless of any knowledge
         thereof any such holder may have or be otherwise charged with.

                  (b) Without in any way limiting the generality of the
         foregoing paragraph, the holders of Senior Indebtedness of the Parent
         or the Subsidiary Issuer may, at any time and from time to time,
         without the consent of or notice to the Trustee or the Holders of the
         Parent Notes or the Subsidiary Notes, without incurring responsibility
         to the Holders of the Parent Notes or the Subsidiary Notes and without
         impairing or releasing the subordination provided in this Article or
         the obligations hereunder of the Holders of the Parent Notes or the
         Subsidiary Notes to the holders of Senior Indebtedness of the Parent or
         the Subsidiary Issuer, do any one or more of the following: (i) change
         the manner, place or terms of payment or extend the time of payment of,
         or renew or alter, Senior Indebtedness of the Parent or the Subsidiary
         Issuer, or otherwise amend or supplement in any

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<PAGE>
         manner Senior Indebtedness of the Parent or the Subsidiary Issuer or
         any instrument evidencing the same or any agreement under which Senior
         Indebtedness of the Parent or the Subsidiary Issuer is outstanding;
         (ii) sell, exchange, release or otherwise deal with any property
         pledged, mortgaged or otherwise securing Senior Indebtedness of the
         Parent or the Subsidiary Issuer; (iii) release any Person liable in any
         manner for the collection of Senior Indebtedness of the Parent or the
         Subsidiary Issuer; and (iv) exercise or refrain from exercising any
         rights against the Parent or the Subsidiary Issuer and any other
         Person.

                  Section 1208  Notice to Trustee

                  (a) The Parent and the Subsidiary Issuer shall give prompt
         written notice to the Trustee of any fact known to the Parent or the
         Subsidiary Issuer which would prohibit the making of any payment to or
         by the Trustee in respect of the Parent Notes or the Subsidiary Notes.
         Notwithstanding the provisions of this Article or any other provision
         of this Indenture, the Trustee shall not be charged with knowledge of
         the existence of any facts which would prohibit the making of any
         payment to or by the Trustee in respect of the Parent Notes or the
         Subsidiary Notes, unless and until the Trustee shall have received
         written notice thereof from the Parent or the Subsidiary Issuer or a
         holder of Senior Indebtedness of the Parent or the Subsidiary Issuer
         (or from any Representative therefor) with respect to a Payment
         Default, or one or more of the holders of Designated Senior
         Indebtedness (or from any Representative therefor), with respect to a
         Non-Payment Default; and, prior to the receipt of any such written
         notice, the Trustee, subject to the provisions of TIA
         Sections315(a) through 315(d), shall be entitled in all respects
         to assume that no such facts exist; provided, however, that if the
         Trustee shall not have received the notice provided for in this Section
         at least three Business Days prior to the date upon which by the terms
         hereof any money may become payable for any purpose (including, without
         limitation, the payment of the principal of (and premium, if any) or
         interest on any Parent Notes or Subsidiary Notes), then, anything
         herein contained to the contrary notwithstanding, the Trustee shall
         have full power and authority to receive such money and to apply the
         same to the purpose for which such money was received and shall not be
         affected by any notice to the contrary which may be received by it
         within three Business Days prior to such date.

                  (b) Subject to TIA Sections315(a) through 315(d), the
         Trustee shall be entitled to rely on the delivery to it of a written
         notice by a Person representing himself to be a holder of Senior
         Indebtedness of the Parent or the Subsidiary Issuer (or a trustee
         therefor) to establish that such notice has been given by a holder of
         Senior Indebtedness of the Parent or the Subsidiary Issuer (or a
         trustee therefor). In the event that the Trustee determines in good
         faith that further evidence is required with respect to the right of
         any Person as a holder of Senior Indebtedness of the Parent or the
         Subsidiary Issuer to participate in any payment or distribution
         pursuant to this Article, the Trustee may request such Person to
         furnish evidence to the reasonable satisfaction of the Trustee as to
         the amount of Senior Indebtedness of the Parent or the Subsidiary
         Issuer held by such Person,

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         the extent to which such Person is entitled to participate in such
         payment or distribution and any other facts pertinent to the rights of
         such Person under this Article.

                  Section 1209  Reliance on Judicial Order or Certificate of
Liquidating Agent

                  Upon any payment or distribution of assets of the Parent or
         the Subsidiary Issuer referred to in this Article, the Trustee, subject
         to TIA Sections 315(a) through 315(d), and the Holders of the
         Parent and the Subsidiary Notes shall be entitled to rely upon any
         order or decree entered by any court of competent jurisdiction, or a
         certificate of the trustee in bankruptcy, receiver, liquidating
         trustee, custodian, assignee for the benefit of creditors, agent or
         other Person making such payment or distribution, delivered to the
         Trustee or to the Holders, for the purpose of ascertaining the Persons
         entitled to participate in such payment or distribution, the holders of
         the Senior Indebtedness of the Parent and the Subsidiary Issuer, the
         amount thereof or payable thereon, the amount or amounts paid or
         distributed thereon and all other facts pertinent thereto or to this
         Article.

                  Section 1210  Trustee Not Fiduciary for Holders of Senior
Indebtedness

                  The Trustee shall not be deemed to owe any fiduciary duty to
         the holders of Senior Indebtedness of the Parent or the Subsidiary
         Issuer and shall not be liable to any such holders if the Trustee shall
         in good faith mistakenly pay over or distribute to Holders of Parent
         Notes or Subsidiary Notes, as the case may be, or to the Parent or the
         Subsidiary Issuer or to any other Person cash, property or securities
         to which any holders of Senior Indebtedness of the Parent or the
         Subsidiary Issuer shall be entitled by virtue of this Article or
         otherwise.

                  Section 1211  Rights of Trustee as Holder of Senior
Indebtedness; Preservation of Trustee's Rights

                  The Trustee in its individual capacity shall be entitled to
         all the rights set forth in this Article with respect to any Senior
         Indebtedness of the Parent or the Subsidiary Issuer which may at any
         time be held by it, to the same extent as any other holder of Senior
         Indebtedness of the Parent or the Subsidiary Issuer, and nothing in
         this Indenture shall deprive the Trustee of any of its rights as such
         holder.

                  Nothing in this Article shall apply to claims of, or payments
         to, the Trustee under or pursuant to Section 607."


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         SECTION 2.11. PARENT GUARANTEE

         Each of the Original Indentures is hereby supplemented and amended by
the addition of a new Article Thirteen which shall read in its entirety as
follows:

                                "Article Thirteen

                                PARENT GUARANTEE

                  Section 1301  Parent Guarantee

                  The Parent hereby unconditionally guarantees to each Holder of
         a Subsidiary Note authenticated and delivered by the Trustee and to the
         Trustee and its successors and assigns, irrespective of the validity
         and enforceability of this Indenture, the Notes, the Units or the
         obligations of the Subsidiary Issuer or the Parent hereunder or
         thereunder, that: (a) the principal of, premium, if any, and interest
         on the Subsidiary Notes will be promptly paid in full when due, whether
         at maturity, by acceleration, redemption or otherwise, and interest on
         the overdue principal of, premium, and interest on the Subsidiary
         Notes, if any, if lawful, and all other obligations of the Subsidiary
         Issuer to the Holders or the Trustee hereunder or thereunder will be
         promptly paid in full or performed, all in accordance with the terms
         hereof and thereof; and (b) in case of any extension of time of payment
         or renewal of any Subsidiary Notes or any of such other obligations,
         that same will be promptly paid in full when due or performed in
         accordance with the terms of the extension or renewal, whether at
         stated maturity, by acceleration or otherwise. Failing payment when due
         of any amount so guaranteed or any performance so guaranteed for
         whatever reason, the Parent shall be obligated to pay the same
         immediately. The Parent agrees that this Parent Guarantee is a general
         unsecured senior subordinated obligation of the Parent and it is a
         guarantee of payment and not a guarantee of collection.

                  The Parent hereby agrees that its obligations hereunder shall
         be unconditional, irrespective of the validity, regularity or
         enforceability of the Notes, the Units or this Indenture, the absence
         of any action to enforce the same, any waiver or consent by any Holder
         of the Subsidiary Notes with respect to any provisions hereof or
         thereof, the recovery of any judgment against the Subsidiary Issuer,
         any action to enforce the same or any other circumstance which might
         otherwise constitute a legal or equitable discharge or defense of a
         guarantor. The Parent hereby waives diligence, presentment, demand of
         payment, filing of claims with a court in the event of insolvency or
         bankruptcy of the Subsidiary Issuer, any right to require a proceeding
         first against the Subsidiary Issuer, protest, notice and all demands
         whatsoever and covenants that this Parent Guarantee shall not be
         discharged except by complete performance of the obligations contained
         in the Subsidiary Notes, the Units and this Indenture.

                  If any Holder or the Trustee is required by any court or
         otherwise to return to the Subsidiary Issuer, the Parent, or any
         custodian, trustee, liquidator or other

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<PAGE>
         similar official acting in relation to either the Subsidiary Issuer or
         the Parent any amount paid by the Subsidiary Issuer or the Parent
         either to the Trustee or such Holder, this Parent Guarantee, to the
         extent theretofore discharged, shall be reinstated in full force and
         effect.

                  The Parent agrees that it shall not be entitled to any right
         of subrogation in relation to the Holders in respect of any obligations
         guaranteed hereby until payment in full of all obligations guaranteed
         hereby. The Parent further agrees that, as between the Parent, on the
         one hand, and the Holders and the Trustee, on the other hand, (x) the
         maturity of the obligations guaranteed hereby may be accelerated as
         provided in Article Five hereof for the purposes of this Parent
         Guarantee, notwithstanding any stay, injunction or other prohibition
         preventing such acceleration in respect of the obligations guaranteed
         hereby, and (y) in the event of any declaration of acceleration of such
         obligations as provided in Article Five hereof, such obligations
         (whether or not due and payable) shall forthwith become due and payable
         by the Parent for the purpose of this Parent Guarantee.

                  Section 1302  Limitation of Parent's Liability under Parent
Guarantee

                  The Parent, and by its acceptance hereof each Holder, hereby
         confirm that it is the intention of all such parties that the Parent
         Guarantee not constitute a fraudulent transfer or conveyance for
         purposes of the Federal Bankruptcy Code, the Uniform Fraudulent
         Conveyance Act, the Uniform Fraudulent Transfer Act or any similar
         federal or state law. To effectuate the foregoing intention, the
         Holders and the Parent hereby irrevocably agree that the obligations of
         the Parent under the Parent Guarantee will be limited to the maximum
         amount as will, after giving effect to all other contingent and fixed
         liabilities including, but not limited to, Senior Indebtedness of the
         Parent, result in the obligations of the Parent under its Parent
         Guarantee not constituting such a fraudulent conveyance or fraudulent
         transfer. This Section 1302 is for the benefit of the creditors of the
         Parent.

                  Section 1303  Subordination of Parent Guarantee

                  The obligations of the Parent under the Parent Guarantee
         pursuant to this Article Thirteen shall be subordinated in right of
         payment to the prior payment in full of all the obligations of the
         Parent under its Senior Indebtedness (including any guarantees
         constituting Senior Indebtedness and any Designated Senior Indebtedness
         of the Parent) on the same basis as the Parent Notes are subordinated
         to the Senior Indebtedness of the Parent. For the purposes of the
         foregoing sentence, the Trustee and the Holders shall have the right to
         receive and/or retain payments by the Parent under the Parent Guarantee
         only at such times as they may receive and/or retain payments in
         respect of the Parent Notes pursuant to this Indenture, including
         Article Twelve hereof.

                  Section 1304  Defeasance of this Article Thirteen


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                  The subordination of the Parent Guarantee provided by this
         Article is expressly made subject to the provisions for defeasance or
         covenant defeasance in Article Fifteen hereof and, anything herein to
         the contrary notwithstanding, upon the effectiveness of any such
         defeasance or covenant defeasance, the Subsidiary Notes then
         outstanding shall thereupon cease to be subordinated pursuant to this
         Article."

                                  ARTICLE III

                                  MISCELLANEOUS

         SECTION 3.1. INTEGRAL PART

         This First Supplemental Indenture constitutes an integral part of the
Indenture.

         SECTION 3.2. GENERAL DEFINITIONS

         For all purposes of this First Supplemental Indenture:

         capitalized terms used herein without definition shall have the
meanings specified in the Original Indenture

         SECTION 3.3. ADOPTION, RATIFICATION AND CONFIRMATION

         The Original Indentures, as supplemented and amended by this First
Supplemental Indenture, are in all respects hereby adopted, ratified and
confirmed.

         SECTION 3.4. COUNTERPARTS

         This First Supplemental Indenture may be executed in any number of
counterparts, each of which when so executed shall be deemed an original; and
all such counterparts shall together constitute but one and the same instrument.

         SECTION 3.5. BENEFITS OF INDENTURE

         Nothing in this First Supplemental Indenture, the Parent Notes, the
Subsidiary Notes, the Parent Guarantee, the Units or the Indenture, express or
implied, shall give to any Person (other than the parties hereto, any Paying
Agent, any Securities Registrar and their successors hereunder and the Holders)
any benefit or any legal or equitable right, remedy or claim under the
Indenture.

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         SECTION 3.6. GOVERNING LAW

         THIS FIRST SUPPLEMENTAL INDENTURE, THE PARENT NOTES, THE SUBSIDIARY
NOTES, THE PARENT GUARANTEE, THE UNITS AND THE INDENTURE SHALL BE GOVERNED BY
AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

         SECTION 3.7. NOTICES

         Any notice or communication shall be in writing and delivered in
person, by telecopier or overnight air courier guaranteeing next day delivery or
mailed by first-class mail addressed as follows:

                  if to the Parent:

                  Tom Brown, Inc.
                  555 Seventeenth Street, Suite 1850
                  Denver, Colorado  80202
                  Attention:  Daniel G. Blanchard,
                  Executive Vice President, Chief Financial Officer and
                        Treasurer

                  if to the Subsidiary Issuer:

                  Tom Brown Resources Funding Corp.
                  c/o Tom Brown, Inc.
                  555 Seventeenth Street, Suite 1850
                  Denver, Colorado  80202
                  Attention:  Daniel G. Blanchard, Vice President

                  with a copy to:

                  Vinson & Elkins, L.L.P.
                  2300 First City Tower
                  1001 Fannin
                  Houston, Texas  77002
                  Attention:  Jeffery B. Floyd

                  if to the Trustee:

                  U.S. Bank National Association
                  950 17th Street, Suite 300
                  Denver, Colorado 80202
                  Attention:  Corporate Trust Services

         The Parent, the Subsidiary Issuer or the Trustee by notice to the other
may designate additional or different addresses for subsequent notices or
communications.

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<PAGE>
         Any notice or communication mailed to a registered Holder shall be
mailed to the Holder at the Holder's address as it appears on the registration
books of the Registrar and shall be sufficiently given if so mailed within the
time prescribed. Any notice or communication shall also be mailed to any Person
described in TIA Section 3.13(c), to the extent required by the TIA.

         Failure to mail a notice or communication to a Holder or any defect in
it shall not affect its sufficiency with respect to other Holders. If a notice
or communication is mailed in the manner provided above, it is duly given,
whether or not the addressee receives it.

         SECTION 3.8. WHEN NOTES OR UNITS DISREGARDED

         In determining whether the Holders of the required principal amount of
Notes or amount of Units, as the case may be, have concurred in any direction,
waiver or consent, Notes or Units owned by the Parent or the Subsidiary Issuer
or by any Person directly or indirectly controlling or controlled by or under
direct or indirect common control with the Parent or the Subsidiary Issuer shall
be disregarded and deemed not to be outstanding, except that, for the purpose of
determining whether the Trustee shall be protected in relying on any such
direction, waiver or consent, only Notes or Units, as the case may be, which the
Trustee knows are so owned shall be so disregarded. Also, subject to the
foregoing, only Notes or Units outstanding at the time shall be considered in
any such determination.

         SECTION 3.9. NO RECOURSE AGAINST OTHERS

         A director, officer, employee or shareholder, as such, of the Parent or
the Subsidiary Issuer shall have any liability for any obligations of the Parent
or the Subsidiary Issuer under this First Supplemental Indenture, the Notes, the
Parent Guarantee, the Units or this Indenture or for any claim based on, in
respect of or by reason of such obligations or their creation. By accepting the
Notes, the Parent Guarantee and the Units, each Holder shall waive and release
all such liability. Such waiver and release are part of the consideration for
the issue of the Notes, the Parent Guarantee and the Units.

         SECTION 3.10. WAIVER OF IMMUNITIES

         To the extent that the Subsidiary Issuer or any of its subsidiaries or
any of their respective properties, assets or revenues may have or may hereafter
become entitled to, or have attributed to its, any right of immunity, on the
grounds of sovereignty or otherwise, from any legal action, suit or proceeding,
from the giving of any relief in any such legal action, suit or proceeding, from
setoff or counterclaim, from the competent jurisdiction of any court, from
service of process, from attachment upon or prior to judgment, from attachment
in aid of execution of judgment, or from execution of judgment, or from other
legal process or proceeding for the giving of any relief or for the enforcement
of any judgment, in any competent jurisdiction in which proceedings may at
anytime be commenced, with respect to its obligations, liabilities or any other
matter under or arising out of or in connection with this indenture the Notes or
the Units and the transactions contemplated hereby, the Subsidiary Issuer hereby
irrevocably and unconditionally waives and agrees not to please or claim, any
such immunity and consent to such relief and enforcement.


                                      109
<PAGE>
         SECTION 3.11. CONSENT TO JURISDICTION; APPOINTMENT OF AGENT FOR SERVICE
OF PROCESS; JUDGMENT CURRENCY

         (A) The Subsidiary Issuer agrees that any suit, action or proceeding
against the Subsidiary Issuer arising out of or relating to this Indenture the
Notes or the Units may be instituted in any state or U.S. Federal court in the
Borough of Manhattan, The City of New York, New York, and any appellate court
from any thereof, and the Subsidiary Issuer irrevocably submits to the
non-exclusive jurisdiction of such courts in any suit, action or proceeding. The
Subsidiary Issuer irrevocably waives, to the fullest extent permitted by law,
any objection to any suit, action, or proceeding that may be brought in
connection with this Indenture the Notes or the Units, including such actions,
suits or proceedings relating to securities laws of the Unites States of America
or any state thereof, in such courts whether on the grounds of venue, residence
or domicile or on the ground that any such suit, action or proceeding has been
brought in an inconvenient forum. The Subsidiary Issuer agrees that final
judgment in any such suit, action or proceeding brought in such court shall be
conclusive and binding upon the Subsidiary Issuer and may be enforced in any
court to the jurisdiction of which the Subsidiary Issuer is subject by a suit
upon such judgment; provided that service of process is affected upon the
Subsidiary Issuer Guarantor, as the case may be, in the manner provided by this
Section 3.10.

         (B) The Subsidiary Issuer organized under the laws of Nova Scotia,
Canada irrevocably appoints the Parent as its authorized agent (the "Authorized
Agent"), upon whom process may be served in any suit, action or proceeding
arising out of or relating to this Indenture, the Notes, the Units or the
transactions contemplated herein which may be instituted in any state or U.S.
Federal court in the Borough of Manhattan, The City of New York, New York, and
expressly accepts the non-exclusive jurisdiction of any such court in respect of
any such suit, action or proceeding. The Subsidiary Issuer hereby represents and
warrants that the Authorized Agent has accepted such appointment and has agreed
to act as said agent for service of process, and the Subsidiary Issuer agrees to
take any and all action, including the filing of any and all documents that may
be necessary to continue such respective appointment in full force and effect
for a period of ten years from the date of this Indenture. Service of process
upon the Authorized Agent shall be deemed, in every respect, effective service
of process upon the Subsidiary Issuer.


                                      110
<PAGE>
         In Witness Whereof, the parties hereto have caused this Indenture to be
duly executed as of the day and year first above written.

                                        TOM BROWN, INC.



                                        By:.....................................
                                             Name:
                                             Title:

                                        TOM BROWN RESOURCES FUNDING CORP.



                                        By:.....................................
                                             Name:
                                             Title:


                                        U.S. BANK NATIONAL ASSOCIATION, as
                                        Trustee



                                        By:.....................................
                                             Name:
                                             Title:



                                      111
<PAGE>
                                                                       EXHIBIT A

                                 Tom Brown, Inc.

             7.25% Senior Subordinated Notes due September 15, 2013

                                THIS PARENT NOTE
COMPRISES A UNIT WITH A SUBSIDIARY NOTE. THIS PARENT NOTE WILL NOT BE SEPARABLE
       FROM SUCH SUBSIDIARY NOTE AND WILL BE TRANSFERABLE ONLY AS A UNIT.

No. A-___                                                       U.S.$___________


      Tom Brown, Inc., a corporation duly organized and existing under the laws
of the State of Delaware (herein called the "Parent"), for value received,
hereby promises to pay to Cede & Co. or registered assigns, the principal sum of
U.S.$____________ (_____________________ U.S. DOLLARS), as revised by the
Schedule of Increases and Decreases in the Parent Note attached hereto, on
September 15, 2013. Reference is hereby made to the further provisions of this
Parent Note set forth on the reverse hereof, which further provisions shall for
all purposes have the same effect as if set forth at this place.

      Unless the certificate of authentication hereon has been duly executed by
the Trustee by manual signature, this Parent Note shall not be entitled to any
benefit under the Indenture, or be valid or obligatory for any purpose.

      IN WITNESS WHEREOF, the Parent has caused this instrument to be duly
executed.

Date:  __________________                  TOM BROWN, INC.,


                                           By:
                                               ---------------------------------
                                               Name:
                                               Title:







                                      A-1
<PAGE>



                     TRUSTEE'S CERTIFICATE OF AUTHENTICATION

      This is one of the Parent Notes referred to in the within-mentioned
Indenture.

                                               U.S.  BANK NATIONAL ASSOCIATION,
                                                   as Trustee

                                               By
                                                  ------------------------------
                                                   Authorized Officer
Date:  _______________



                                      A-2
<PAGE>

                            (Reverse of Parent Note)

      This Parent Note is one of a duly authorized issue of securities of the
Parent designated as its 7.25% Senior Subordinated Notes due September 15, 2013
(herein called the "Parent Notes"), which are issued under an indenture, as
amended by the First Supplemental Indenture thereto, (herein called the
"Indenture") each dated as of September 16, 2003 among the Parent, Tom Brown
Resources Funding Corp. (the "Subsidiary Issuer"), U.S. Bank National
Association, as trustee (herein called the "Trustee", which term includes any
successor trustee under the Indenture), to which reference is hereby made for a
statement of the respective rights, limitations of rights, duties, obligations
and immunities thereunder of the Parent, the Subsidiary Issuer, the Trustee and
the Holders of the Parent Notes, and of the terms upon which the Parent Notes
are, and are to be, authenticated and delivered. This Parent Note is a global
security representing U.S.$____________ aggregate principal amount of the Parent
Notes.

      This Parent Note, together with the 7.25% Senior Subordinated Notes due
2013 of the Subsidiary Issuer (the "Subsidiary Notes", and together with the
Parent Notes, the "Notes") comprise a unit (each a "Unit" and together, the
"Units"). This Parent Note is not transferable except as a Unit.

      The Parent will pay interest semiannually on March 15 and September 15 of
each year commencing March 15, 2004. The Parent shall pay interest on overdue
principal or premium, if any (plus interest on such interest to the extent
lawful), at the rate borne by the Parent Notes to the extent lawful. Interest on
the Parent Notes shall be computed on the basis of a 360-day year of twelve
30-day months

      Payment of principal, premium, if any, and interest on this Parent Note
will be made at the office or agency of the Parent maintained for that purpose
in The City of New York, New York or at such other office or agency of the
Parent as may be maintained for such purpose; provided, however, that payment of
interest may be made at the option of the Parent by check mailed to the address
of the Persons entitled thereto as such address shall appear on the Registrar.
Initially, U.S. Bank National Association, the Trustee under the Indenture, will
act as Paying Agent and Registrar. The Parent may change any Paying Agent or
Registrar without the consent of, or notice to, any Holder. The Parent may act
in any such capacity. Payment of principal, premium, if any, and interest on the
Parent Notes will be made by wire transfer of immediately available funds to the
accounts specified by The Depository Trust Company ("DTC").

      On and after September 15, 2008 and prior to maturity, the Parent and the
Subsidiary Issuer jointly may redeem all or, from time to time, part of the
Notes as whole Units, upon not less than 30 nor more than 60 days' notice mailed
to each Holder of Units at such Holder's address appearing in the Register, as
whole Units or an integral multiple of a whole Unit, at the following Redemption
Prices (expressed as percentages of the principal amount) plus accrued and
unpaid interest on the Notes comprising the Units, if any, to but excluding the
Redemption Date (subject to the right of Holders of record on the relevant
regular record date to receive interest due on an Interest Payment Date that is
on or prior to the Redemption Date), if redeemed during the 12-month period
beginning on September 15 of the years indicated below:

                                      A-3
<PAGE>
<TABLE>
<CAPTION>
Year                                         Redemption Price
----                                         ----------------
<S>                                          <C>
2008.............................                103.625%
2009.............................                102.417%
2010.............................                101.208%
2011 and thereafter..............                100.000%
</TABLE>


      Prior to September 15, 2006, the Parent and the Subsidiary Issuer jointly
may on one or more occasions redeem up to an aggregate amount equal to 35% of
the original amount of the Units, including any Additional Units, with the Net
Cash Proceeds of one or more Equity Offerings at a redemption price of 107.25%
of the principal amount of the Notes comprising the Units, plus accrued and
unpaid interest, if any, to the redemption date (subject to the right of Holders
of record on the relevant record date to receive interest due on the relevant
interest payment date); provided, that (i) there is a Public Market at the time
of such redemption, (ii) at least 65% of the original amount of the Units,
including any Additional Units, remains outstanding after each such redemption
and (iii) the redemption occurs within 90 days after the closing of such Equity
Offering.

      In the case of any partial redemption, selection of the Notes, as whole
Units, for redemption will be made by the Trustee in compliance with the
requirements of the principal national securities exchange, if any, on which the
Units or Notes are listed or, if the Units and Notes are not listed, then on a
pro rata basis, by lot or by such other method as the Trustee in its sole
discretion will deem to be fair and appropriate, although no Unit will be
redeemed in part. Units in an amount equal to, and representing the same
Indebtedness as, the unredeemed portion thereof will be issued in the name of
the Holder thereof upon cancellation of the original Notes and Units.

      The Notes, as whole Units, will be subject to redemption at the joint
option of the Parent and the Subsidiary Issuer, as a whole but not in part, at
any time upon not fewer than 30 nor more than 60 days' notice mailed to each
Holder of Units at the addresses appearing in the Register at a redemption price
equal to 100% of the principal amount of the Notes comprising the Units plus
accrued interest to but excluding the Redemption Date if the Subsidiary Issuer
has become or would become obligated to pay on the next date on which any amount
would be payable under or with respect to the Subsidiary Notes, any Additional
Amounts as a result of any change or amendment to the laws (or regulations
promulgated thereunder) of Canada (or any political subdivision or taxing
authority thereof or therein) (collectively, a "Taxing Authority"), or any
change in or amendment to any official position or administration or assessing
practices regarding the application or interpretation of such laws or
regulations, which change or amendment is announced or becomes effective on or
after the date of the Indenture.

      If an Event of Default shall occur and be continuing, the principal of all
the Parent Notes may be declared due and payable in the manner and with the
effect provided in the Indenture.

      The Indenture contains provisions for defeasance of (a) the entire
indebtedness of the Parent on this Parent Note and (b) certain restrictive
covenants and the related Events of


                                      A-4
<PAGE>

Default, subject to compliance by the Parent, with certain conditions set forth
in the Indenture, which provisions apply to this Parent Note.

      The Indenture permits, with certain exceptions as therein provided, the
amendment thereof and the modification of the rights and obligations of the
Parent and the rights of the Holders of the Units under the Indenture at any
time by the Parent, the Subsidiary Issuer and the Trustee with the consent of
the Holders of a majority in aggregate principal amount of the Notes comprising
the Units at the time outstanding. The Indenture also contains provisions
permitting the Holders of specified percentages in aggregate principal amount of
the Notes comprising the Units at the time outstanding, on behalf of the Holders
of all the Units, to waive compliance by the Parent and the Subsidiary Issuer
with certain provisions of the Indenture and certain past defaults under the
Indenture and their consequences. Any such consent or waiver by or on behalf of
the Holder of this Parent Note shall be conclusive and binding upon such Holder
and upon all future Holders of this Parent Note and of any Parent Note issued
upon the registration of transfer hereof or in exchange herefor or in lieu
hereof whether or not notation of such consent or waiver is made upon this
Parent Note.

      As provided for in the Indenture, the Parent may, subject to certain
limitations, from time to time, without notice to or the consent of the Holders,
create and issue Additional Notes, as whole Units, so that such Additional Notes
shall be consolidated and form a single series with the Parent Notes initially
issued by the Parent and shall have the same terms as to status, redemption or
otherwise as the Parent Notes originally issued. Any Additional Notes shall be
issued with the benefit of an indenture supplemental to the Indenture.

      No reference herein to the Indenture and no provision of this Parent Note
or of the Indenture shall alter or impair the obligation of the Parent, which is
absolute and unconditional, to pay the principal of (and premium, if any, on)
and interest on this Parent Note at the times, place, and rate, and in the coin
or currency, herein prescribed.

      The Parent Notes are issuable only in registered form without coupons as
part of Units consisting of Parent Notes in denominations of U.S.$512 and
Subsidiary Notes in denominations of U.S. $488, and any integral multiple of
whole Unit.

      No service charge shall be made for any registration of transfer or
exchange of the Parent Notes, but the Parent may require payment of a sum
sufficient to cover any tax or other governmental charge payable in connection
therewith.

      Capitalized terms used herein that are not otherwise defined shall have
the meanings ascribed to them in the Indenture.

      The Indenture and this Parent Note shall be governed by, and construed in
accordance with, the laws of the State of New York.



                                      A-5
<PAGE>

                SCHEDULE OF INCREASES OR DECREASES IN PARENT NOTE

      The following increases or decreases in this Parent Note have been made:
<TABLE>
<S>              <C>                      <C>                      <C>                      <C>
                                                                   Principal Amount of      Signature of
                 Amount of decrease in    Amount of increase in    this Parent Note         authorized signatory
Date of          Principal Amount of      Principal Amount of      following such           of Trustee or
Exchange         this Parent Note         this Parent Note         decrease or increase     Securities Custodian
--------         ---------------------    ---------------------    --------------------     --------------------
</TABLE>


                                      A-1
<PAGE>
                                                                       EXHIBIT B

                        Tom Brown Resources Funding Corp.
                    7.25% Senior Subordinated Notes due 2013

                              THIS SUBSIDIARY NOTE
COMPRISES A UNIT WITH A PARENT NOTE. THIS SUBSIDIARY NOTE WILL NOT BE SEPARABLE
         FROM SUCH PARENT NOTE AND WILL BE TRANSFERABLE ONLY AS A UNIT.

No. ____                                                        U.S.$___________


      Tom Resources Funding Corp., an unlimited company organized under the laws
of Nova Scotia, Canada (herein called the "Subsidiary Issuer"), for value
received, hereby promises to pay to Cede & Co. or registered assigns, the
principal sum of U.S.$____________ (______________________ U.S. DOLLARS), as
revised by the Schedule of Increases and Decreases in the Subsidiary Note
attached hereto, on September 15, 2013. Reference is hereby made to the further
provisions of this Subsidiary Note set forth on the reverse hereof, which
further provisions shall for all purposes have the same effect as if set forth
at this place.

      Unless the certificate of authentication hereon has been duly executed by
the Trustee by manual signature, this Subsidiary Note shall not be entitled to
any benefit under the Indenture, or be valid or obligatory for any purpose.

      IN WITNESS WHEREOF, the Subsidiary Issuer has caused this instrument to be
duly executed.

Date:  ______________                 TOM BROWN RESOURCES FUNDING CORP.


                                      By:
                                             -----------------------------------
                                             Name:
                                             Title:







                                      B-1
<PAGE>



                     TRUSTEE'S CERTIFICATE OF AUTHENTICATION

      This is one of the Subsidiary Notes referred to in the within-mentioned
Indenture.

                                  U.S. BANK NATIONAL ASSOCIATION,
                                      as Trustee

                                  By
                                     -------------------------------------------
                                     Authorized Officer


Date:  ______________








                                      B-2
<PAGE>



                          (Reverse of Subsidiary Note)

      This Subsidiary Note is one of a duly authorized issue of securities of
the Subsidiary Issuer designated as its 7.25% Senior Subordinated Notes due
September 15, 2013 (herein called the "Subsidiary"), which are issued under an
indenture, as amended by the First Supplemental Indenture thereto, (herein
called the "Indenture") each dated as of September 16, 2003 among Tom Brown,
Inc. (the "Parent"), the Subsidiary Issuer, U.S. Bank National Association, as
trustee (herein called the "Trustee", which term includes any successor trustee
under the Indenture), to which reference is hereby made for a statement of the
respective rights, limitations of rights, duties, obligations and immunities
thereunder of the Parent, the Subsidiary Issuer, the Trustee and the Holders of
the Subsidiary Notes, and of the terms upon which the Subsidiary Notes are, and
are to be, authenticated and delivered. This Subsidiary Note is a global
security representing U.S.$_____________ aggregate principal amount of the
Subsidiary Notes.

      This Subsidiary Note is unconditionally guaranteed on a senior
subordinated basis as to payment of principal, premium, if any, and interest by
the Parent pursuant to the terms of the Indenture.

      This Subsidiary Note, together, with the 7.25% Senior Subordinated Notes
due September 15, 2013 of the Parent (the "Parent Notes", and together with the
Subsidiary Notes, the "Notes") comprise a unit (each a "Unit" and together, the
"Units"). This Subsidiary Note is not transferable except as a Unit.

      The Subsidiary Issuer will pay interest semiannually on March 15 and
September 15 of each year commencing March 15, 2004. The Subsidiary Issuer shall
pay interest on overdue principal or premium, if any (plus interest on such
interest to the extent lawful), at the rate borne by the Subsidiary Notes to the
extent lawful. Interest on the Subsidiary Notes shall be computed on the basis
of a 360-day year of twelve 30-day months. Solely for purposes of the Interest
Act (Canada), the yearly rate of interest to which interest calculated for a
period of less than one year on the basis of a year of 360 days consisting of 12
30-day periods is equivalent is such rate of interest multiplied by a fraction
of which (i) the numerator is the product of (A) the actual number of days in
the year commencing on the first day of such period, multiplied by (B) the sum
of (y) the product of 30 multiplied by the number of complete months elapsed in
such period and (z) the actual number of days elapsed in any incomplete month in
such period; and (ii) the denominator is the product of (a) 360 multiplied by
(b) the actual number of days in such period. The Trustee shall have no
obligation to calculate interest under the Interest Act (Canada).

      Payment of principal, premium, if any, and interest on this Subsidiary
Note will be made at the office or agency of the Subsidiary Issuer maintained
for that purpose in The City of New York, New York or at such other office or
agency of the Subsidiary Issuer as may be maintained for such purpose; provided,
however, that payment of interest may be made at the option of the Subsidiary
Issuer by check mailed to the address of the Persons entitled thereto as such
address shall appear on the Registrar. Initially, U.S. Bank National
Association, the Trustee under the Indenture, will act as Paying Agent and
Registrar. The Subsidiary Issuer may change any Paying Agent or Registrar
without the consent of, or notice to, any Holder. The Subsidiary Issuer may act
in any such capacity. Payment of principal, premium, if any, and interest on
this Subsidiary Note will be made by wire transfer of immediately available
funds to the accounts specified by The Depository Trust Company ("DTC").

                                      B-3
<PAGE>

      On and after September 15, 2008 and prior to maturity, the Parent and the
Subsidiary Issuer jointly may redeem all or, from time to time, part of the
Notes as whole Units, upon not less than 30 nor more than 60 days' notice mailed
to each Holder of Units at such Holder's address appearing in the Register, as
whole Units or an integral multiple of a whole Unit, at the following Redemption
Prices (expressed as percentages of the principal amount) plus accrued and
unpaid interest on the Notes comprising the Units, if any, to but excluding the
Redemption Date (subject to the right of Holders of record on the relevant
regular record date to receive interest due on an Interest Payment Date that is
on or prior to the Redemption Date), if redeemed during the 12-month period
beginning September 15 of the years indicated below:
<TABLE>
<CAPTION>
Year                                         Redemption Price
----                                         ----------------
<S>                                          <C>
2008.............................                 103.625%
2009.............................                 102.417%
2010.............................                 101,208%
2011 and thereafter..............                 100.000%
</TABLE>


      Prior to September 15, 2006, the Parent and the Subsidiary Issuer jointly
may on one or more occasions redeem up to an aggregate amount equal to 35% of
the original amount of the Units, including any Additional Units, with the Net
Cash Proceeds of one or more Equity Offerings at a redemption price of 107.25%
of the principal amount of the Notes comprising the Units, plus accrued and
unpaid interest, if any, to the redemption date (subject to the right of Holders
of record on the relevant record date to receive interest due on the relevant
interest payment date); provided, that (i) there is a Public Market at the time
of such redemption, (ii) at least 65% of the original amount of the Units,
including any Additional Units, remains outstanding after each such redemption
and (iii) the redemption occurs within 90 days after the closing of such Equity
Offering.

      In the case of any partial redemption, selection of the Notes, as whole
Units, for redemption will be made by the Trustee in compliance with the
requirements of the principal national securities exchange, if any, on which the
Units or Notes are listed or, if the Units and Notes are not listed, then on a
pro rata basis, by lot or by such other method as the Trustee in its sole
discretion will deem to be fair and appropriate, although no Unit will be
redeemed in part. Units in an amount equal to, and representing the same
Indebtedness as, the unredeemed portion thereof will be issued in the name of
the Holder thereof upon cancellation of the original Notes and Units.

      The Notes, as whole Units, will be subject to redemption at the joint
option of the Parent and the Subsidiary Issuer, as a whole but not in part, at
any time upon not fewer than 30 nor more than 60 days' notice mailed to each
Holder of Units at the addresses appearing in the Register at a redemption price
equal to 100% of the principal amount of the Notes comprising the Units plus
accrued interest to but excluding the Redemption Date if the Subsidiary Issuer
has become or would become obligated to pay on the next date on which any amount
would be payable under or with respect to the Subsidiary Notes, any Additional
Amounts as a result of any change or amendment to the laws (or regulations
promulgated thereunder) of Canada (or any political subdivision or taxing
authority thereof or therein) (collectively, a "Taxing Authority"), or any
change in or amendment to any official position or administration or assessing
practices


                                      B-4
<PAGE>

regarding the application or interpretation of such laws or regulations, which
change or amendment is announced or becomes effective on or after the date of
the Indenture.

      If an Event of Default shall occur and be continuing, the principal of all
the Subsidiary Notes may be declared due and payable in the manner and with the
effect provided in the Indenture.

      The Indenture contains provisions for defeasance of (a) the entire
indebtedness of the Subsidiary Issuer on this Subsidiary Note and (b) certain
restrictive covenants and the related Events of Default, subject to compliance
by the Subsidiary Issuer, with certain conditions set forth in the Indenture,
which provisions apply to this Subsidiary Note.

      As provided for in the Indenture, the Subsidiary Issuer may, subject to
certain limitations, from time to time, without notice to or the consent of the
Holders, create and issue Additional Notes so that such Additional Notes shall
be consolidated and form a single series with the Subsidiary Notes initially
issued by Subsidiary Issuer and shall have the same terms as to status,
redemption or otherwise as the Subsidiary Notes originally issued. Any
Additional Notes shall be issued with the benefit of an indenture supplemental
to the Indenture.

      The Indenture permits, with certain exceptions as therein provided, the
amendment thereof and the modification of the rights and obligations of the
Subsidiary Issuer and the rights of the Holders of the Units under the Indenture
at any time by the Parent, the Subsidiary Issuer and the Trustee with the
consent of the Holders of a majority in aggregate principal amount of the Notes
comprising the Units at the time outstanding. The Indenture also contains
provisions permitting the Holders of specified percentages in aggregate
principal amount of the Notes comprising the Units at the time outstanding, on
behalf of the Holders of all the Units, to waive compliance by the Parent and
the Subsidiary Issuer with certain provisions of the Indenture and certain past
defaults under the Indenture and their consequences. Any such consent or waiver
by or on behalf of the Holder of this Subsidiary Note shall be conclusive and
binding upon such Holder and upon all future Holders of this Subsidiary Note and
of any Subsidiary Note issued upon the registration of transfer hereof or in
exchange herefor or in lieu hereof whether or not notation of such consent or
waiver is made upon this Subsidiary Note.

      No reference herein to the Indenture and no provision of this Subsidiary
Note or of the Indenture shall alter or impair the obligation of the Subsidiary
Issuer, which is absolute and unconditional, to pay the principal of (and
premium, if any, on) and interest on this Subsidiary Note at the times, place,
and rate, and in the coin or currency, herein prescribed.

      The Subsidiary Notes are issuable only in registered form without coupons
as part of Units consisting of Subsidiary Notes in denominations of U.S.$488 and
Parent Notes in denominations of U.S.$512, and any integral multiple of a whole
Unit.

      No service charge shall be made for any registration of transfer or
exchange of Subsidiary Notes, but the Subsidiary Issuer may require payment of a
sum sufficient to cover any tax or other governmental charge payable in
connection therewith.

      Capitalized terms used herein that are not otherwise defined shall have
the meanings ascribed to them in the Indenture.

                                      B-5
<PAGE>

      The Indenture and this Subsidiary Note shall be governed by, and construed
in accordance with, the laws of the State of New York.



                                      B-6
<PAGE>




             SCHEDULE OF INCREASES OR DECREASES IN SUBSIDIARY NOTE


The following increases or decreases in this Subsidiary Note have been made:
<TABLE>
<S>              <C>                      <C>                      <C>                      <C>
                                                                   Principal Amount of      Signature of
                 Amount of decrease in    Amount of increase in    this Subsidiary Note     authorized signatory
Date of          Principal Amount of      Principal Amount of      following such           of Trustee or
Exchange         this Subsidiary  Note    this Subsidiary Note     decrease or increase     Securities Custodian
-------          ---------------------    ---------------------    --------------------     --------------------
</TABLE>







                                      B-1
<PAGE>




                                                                       EXHIBIT C

                            FORM OF PARENT GUARANTEE
                                       OF
                                 TOM BROWN, INC.

      Reference is made to the indenture, as amended by the First Supplemental
Indenture thereto, (herein called the "Indenture") each dated as of
_____________ among Tom Brown Inc., a corporation duly organized and existing
under the laws of the state of Delaware (herein called the "Parent"), Tom Brown
Resources Funding Corp., an unlimited company existing under the laws of Nova
Scotia, Canada (herein called the "Subsidiary Issuer"), and U.S. Bank National
Association, as trustee (herein called the "Trustee"), under which the Parent
issued an aggregate of U.S.$____________ principal amount of 7.25% Senior
Subordinated Notes due September 15, 2013 of the Parent (the "Parent Notes") and
the Subsidiary Issuer issued an aggregate of U.S.$_____________ principal amount
of 7.25% Senior Subordinated Notes due September 15, 2003 of the Subsidiary
Issuer (the "Subsidiary Notes", and together with the Parent Notes, the
"Notes"), unconditionally guaranteed as to payment of principal, premium, if
any, and interest by the Parent (the "Parent Guarantee"). The Parent Notes and
the Subsidiary Notes (together with the Parent Guarantee) are initially issued
as _______ units (together, the "Units"), each such Unit consisting of (A)
U.S.$512 principal amount of Parent Notes and (B) U.S.$488 principal amount of
Subsidiary Notes (including the Parent Guarantee).

      For value received, the Parent hereby unconditionally guarantees to each
Holder of a Subsidiary Note authenticated and delivered by the Trustee and to
the Trustee and its successors and assigns, irrespective of the validity and
enforceability of the Indenture, the Notes, the Units or the obligations of the
Subsidiary Issuer or the Parent under the Indenture or the Subsidiary Notes,
that: (a) the principal of, premium, if any, and interest on the Subsidiary
Notes will be promptly paid in full when due, whether at maturity, by
acceleration, redemption or otherwise, and interest on the overdue principal of,
premium, and interest on the Subsidiary Notes, if any, if lawful, and all other
obligations of the Subsidiary Issuer to the Holders or the Trustee under the
Indenture or the Subsidiary Notes will be promptly paid in full or performed,
all in accordance with the terms hereof and thereof; and (b) in case of any
extension of time of payment or renewal of any Subsidiary Notes or any of such
other obligations, that same will be promptly paid in full when due or performed
in accordance with the terms of the extension or renewal, whether at stated
maturity, by acceleration or otherwise. Failing payment when due of any amount
so guaranteed or any performance so guaranteed for whatever reason, the Parent
shall be obligated to pay the same immediately. The Parent agrees that this
Parent Guarantee is a general unsecured senior subordinated obligation of the
Parent and it is a guarantee of payment and not a guarantee of collection.

      The Parent hereby agrees that its obligations hereunder shall be
unconditional, irrespective of the validity, regularity or enforceability of the
Notes, the Units or the Indenture, the absence of any action to enforce the
same, any waiver or consent by any Holder of the Subsidiary Notes with respect
to any provisions hereof or thereof, the recovery of any judgment against the
Subsidiary Issuer, any action to enforce the same or any other circumstance
which might otherwise constitute a legal or equitable discharge or defense of a
guarantor. The Parent hereby waives diligence, presentment, demand of payment,
filing of claims with a court in the
<PAGE>

event of insolvency or bankruptcy of the Subsidiary Issuer, any right to require
a proceeding first against the Subsidiary Issuer, protest, notice and all
demands whatsoever and covenants that this Parent Guarantee shall not be
discharged except by complete performance of the obligations contained in the
Subsidiary Notes, the Units and the Indenture.

      If any Holder or the Trustee is required by any court or otherwise to
return to the Subsidiary Issuer, the Parent, or any custodian, trustee,
liquidator or other similar official acting in relation to either the Subsidiary
Issuer or the Parent any amount paid by the Subsidiary Issuer or the Parent
either to the Trustee or such Holder, this Parent Guarantee, to the extent
theretofore discharged, shall be reinstated in full force and effect.

      The Parent agrees that it shall not be entitled to any right of
subrogation in relation to the Holders in respect of any obligations guaranteed
hereby until payment in full of all obligations guaranteed hereby. The Parent
further agrees that, as between the Parent, on the one hand, and the Holders and
the Trustee, on the other hand, (x) the maturity of the obligations guaranteed
hereby may be accelerated as provided in Article Five of the Indenture for the
purposes of this Parent Guarantee, notwithstanding any stay, injunction or other
prohibition preventing such acceleration in respect of the obligations
guaranteed hereby, and (y) in the event of any declaration of acceleration of
such obligations as provided in Article Five of the Indenture, such obligations
(whether or not due and payable) shall forthwith become due and payable by the
Parent for the purpose of this Parent Guarantee.

      Reference is made to Article Thirteen of the Indenture for further
provisions with respect to the Parent Guarantee.

      This Parent Guarantee shall not be valid or obligatory for any purpose
until the certificate of authentication of such Subsidiary Note shall have been
manually executed by or on behalf of the Trustee under such Indenture.

      All terms used in this Parent Guarantee which are defined in such
Indenture shall have the meanings assigned to them in such Indenture.

      This Parent Guarantee shall be governed by and construed in accordance
with the laws of the State of New York.

Date:  _______________                     TOM BROWN, INC.,



                                           By:
                                               ---------------------------------
                                               Name:
                                               Title:
<PAGE>
                                                                       EXHIBIT D

                                 Tom Brown, Inc.
                        Tom Brown Resources Funding Corp.

                            Units Each Consisting of
          U.S.$512 principal amount 7.25% Senior Subordinated Notes of
                   Tom Brown, Inc. due September 15, 2013 and
          U.S.$488 principal amount 7.25% Senior Subordinated Notes of
            Tom Brown Resources Funding Corp. due September 15, 2013

UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR UNITS IN DEFINITIVE
FORM, THIS UNIT MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A
NOMINEE OF THE DEPOSITARY, OR BY THE DEPOSITARY OR NOMINEE OF SUCH DEPOSITARY,
TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY. TRANSFERS
OF THIS GLOBAL UNIT SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN PART, TO
NOMINEES OF CEDE & CO. OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR'S NOMINEE,
AND TRANSFERS OR PORTIONS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS
MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN THE INDENTURE.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE
DEPOSITORY TRUST COMPANY ("DTC") TO THE PARENT AND THE SUBSIDIARY ISSUER OR
THEIR AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY
CERTIFICATE IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS IS
REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT HEREON IS MADE
TO CEDE & CO. OR SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR
OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER
HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.


No. ___                          Certificate for __________ Units Consisting of
CUSIP No. ___________            U.S.$__________  Aggregate Principal
ISIN No. _____________           Amount of 7.25% Senior Subordinated Notes
                                 due September 15, 2013 of Tom Brown, Inc.
                                 and U.S.$ __________ Aggregate Principal
                                 Amount of 7.25% Senior Subordinated Notes
                                 due September 15, 2013 of Tom Brown
                                 Resources Funding Corp.

            Each of Tom Brown, Inc., a corporation duly organized and existing
under the laws of the State of Delaware (the "Parent"), and Tom Brown Resources
Funding Corp., a unlimited company organized under the laws of Nova Scotia
Canada and a wholly owned
<PAGE>
subsidiary of the Parent (the "Subsidiary Issuer"), hereby certifies that Cede &
Co. or registered assigns is the registered holder of U.S.$________ Units as
described above, as revised by the Schedule of Increases and Decreases in the
Units attached hereto,. Each Unit consists of U.S.$512 principal amount of 7.25%
Senior Subordinated Notes due September 15, 2013 of the Parent (the "Parent
Notes"), attached hereto as Exhibit A, and U.S.$488 principal amount of 7.25%
Senior Subordinated Notes due 2013 of the Subsidiary Issuer, attached hereto as
Exhibit B, (the "Subsidiary Notes", and together with the Parent Notes, the
"Notes"). This Unit is issued pursuant to the Indentures, as amended by the
First Supplemental Indenture, (the "Indenture") each dated as of September 16,
2003 among the Parent, the Subsidiary Issuer and U.S. Bank National Association,
as trustee (the "Trustee"), and is subject to the terms and provisions contained
therein, to all of which terms and provisions the holder of this Unit
Certificate consents by acceptance hereof. The terms of the Notes and the Parent
Guarantee are governed by the Indenture, and are subject to the terms and
provisions contained therein, to all of which terms and provisions the holder of
this Unit Certificate consents by acceptance, hereof.

            Each Holder of a Unit shall be deemed to be the Holder, for each
Unit held by such Holder, of U.S.$512 aggregate principal amount of Parent Notes
and U.S.$488 aggregate principal amount of Subsidiary Notes, upon which
principal of, premium, if any, and interest on (and Additional Amounts, if any)
is payable to such Holder on the dates and in the manner provided in the Parent
Notes, the Subsidiary Notes and in the Indenture.

            Reference is made to the further provisions of this Unit Certificate
contained herein, which will for all purposes have the same effect as if set
forth at this place. Copies of the Indenture are on file at the office of the
Parent and the Subsidiary Issuer and are available to any Holder on written
request and without cost.

            The Notes and Parent Guarantee represented by this Unit Certificate
shall nor be detachable or separately transferable at any time.

            If at any time, (i) The Depository Trust Company ("DTC") notifies
the Parent and the Subsidiary Issuer that it is unwilling or unable to continue
as Depositary or if at any time DTC shall no longer be registered or in good
standing under the Securities Exchange Act of 1934, as amended, or other
applicable statute or regulation and a successor Depositary is not appointed by
the Parent and the Subsidiary Issuer within 90 days after the Parent and the
Subsidiary Issuer receive such notice or become aware of such condition, as the
case may be, or (ii) the Parent and the Subsidiary Issuer determine that the
Units shall no longer be represented by a global Security or Securities, then in
such event the Parent and the Subsidiary Issuer will execute, and the Trustee
will authenticate and deliver, Units in definitive registered form, in
authorized denominations, and in an aggregate principal amount equal to the
principal amount of this Global Security in exchange for this Global Security.
Such Units in definitive registered form shall be registered in such names and
issued in such authorized denominations as the Depositary, pursuant to
instructions from its director indirect participants or otherwise, shall
instruct the Trustee. The Trustee shall deliver such Units to the Persons in
whose names such Global Securities are so registered.

            Capitalized terms used herein that are not otherwise defined shall
have the meanings ascribed to them in the Indenture.
<PAGE>
            The Indenture and this Global Security shall be governed by and
construed in accordance with the laws of the State of New York.
<PAGE>
            IN WITNESS WHEREOF, each of the Parent and the Subsidiary Issuer has
caused this instrument to be duly executed.



                                 TOM BROWN, INC.,



                                 By:
                                    --------------------------------------------
                                       Name:
                                       Title:


                                 TOM BROWN RESOURCES FUNDING CORP.


                                 By:
                                    --------------------------------------------
                                       Name:
                                       Title:
Date:
      -----------
<PAGE>
                     TRUSTEE'S CERTIFICATE OF AUTHENTICATION

            This is one of the Units referred to in the within-mentioned
Indenture.

                                       U.S. BANK NATIONAL ASSOCIATION,
                                           as Trustee


                                       By
                                          --------------------------------------
                                       Authorized Officer


Date:
      ----------
<PAGE>
                   SCHEDULE OF INCREASES OR DECREASES IN UNIT

            The following increases or decreases in this Unit have been made:

<TABLE>
<CAPTION>
             Amount of decrease   Amount of increase       Principal Amount of this Unit       Signature of authorized
Date of        in Principal         in Principal             following such decrease or         signatory of Trustee or
Exchange    Amount of this Unit   Amount of this Unit                increase                    Securities Custodian
--------    -------------------   -------------------                --------                    --------------------
<S>        <C>                    <C>                     <C>                                <C>

</TABLE>
<PAGE>
                                                                       EXHIBIT E

          FORM OF SUPPLEMENTAL INDENTURE TO ADD SUBSIDIARY GUARANTORS

      This Supplemental Indenture, dated as of [__________] (this "Supplemental
Indenture" or "Guarantee"), among [NAME OF FUTURE SUBSIDIARY GUARANTOR] (the
"Guarantor"), TOM BROWN, INC. (the "Parent"), TOM BROWN RESOURCES FUNDING CORP.
(the "Subsidiary Issuer") and U.S. BANK NATIONAL ASSOCIATION, a national banking
association, as trustee (the "Trustee") under the Indenture referred to below.



                              W I T N E S S E T H:

      WHEREAS, the Parent has heretofore executed and delivered to the Trustee
an Indenture, dated as of September 16, 2003 relating to its subordinated debt
securities (the "Original Parent Indenture"), providing for the issuance from
time to time of one or more series of the Parents' subordinated debt Securities;

      WHEREAS, the Subsidiary Issuer has heretofore executed and delivered to
the Trustee an Indenture, dated as of September 16, 2003 relating to its
subordinated debt securities (the "Original Subsidiary Issuer Indenture" and,
together with the Original Parent Indenture, the "Original Indentures," and, as
each shall be amended and supplemented by the First Supplemental Indenture, the
"Indenture"), providing for the issuance from time to time of one or more series
of the Subsidiary Issuer's subordinated debt Securities;

      WHEREAS, the Parent, the Subsidiary Issuer and the Trustee have heretofore
executed and delivered a First Supplemental Indenture, dated as of September 16,
2003 (the First Supplemental Indenture), providing for the issuance of 225,000
Units (the "Units") consisting of U.S.$115,200,000 aggregate principal amount of
7.25% Senior Subordinated Notes due September 15, 2013 of Tom Brown, Inc. (the
"Parent Notes") and U.S.$109,800,000 aggregate principal amount of 7.25% Senior
Subordinated Notes due September 15, 2013 of Tom Resources Funding Corp. (the
"Subsidiary Notes" and, collectively with the Parent Notes and the Units, the
"Securities");

      WHEREAS, Section 1013 of the Indenture provides that the Parent will not
permit any Restricted Subsidiary (other than a Foreign Subsidiary) to Guarantee
the payment of any Indebtedness of the Parent or any other Subsidiary unless
such Restricted Subsidiary simultaneously executes and delivers a supplemental
indenture to the Indenture providing for a Subsidiary Guarantee of such
Restricted Subsidiary pursuant to the Indenture; and

      WHEREAS, pursuant to Section 901 of the Indenture, the Parent, the
Subsidiary Issuer and the Trustee are authorized to execute and deliver this
Supplemental Indenture to amend the Indenture, without the consent of any
Holder;

      NOW, THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the
Guarantor, the Parent, the Subsidiary Issuer, the other Subsidiary Guarantors
and the Trustee mutually covenant and agree for the equal and ratable benefit of
the Holders of the Securities as follows:



                                      c-1
<PAGE>
                                    ARTICLE I
                                   Definitions

      SECTION 1.1. Defined Terms. As used in this Supplemental Indenture, terms
defined in the Indenture or in the preamble or recital hereto are used herein as
therein defined, except that the term "Holders" in this Guarantee shall refer to
the term "Holders" as defined in the Indenture and the Trustee acting on behalf
or for the benefit of such Holders. The words "herein," "hereof" and "hereby"
and other words of similar import used in this Supplemental Indenture refer to
this Supplemental Indenture as a whole and not to any particular section hereof.

                                   ARTICLE II
                        Agreement to be Bound; Guarantee

      SECTION 2.1. Agreement to be Bound. The Guarantor hereby becomes a party
to the Indenture as a Subsidiary Guarantor and as such will have all of the
rights and be subject to all of the obligations and agreements of a Subsidiary
Guarantor under the Indenture. The Guarantor agrees to be bound by all of the
provisions of the Indenture applicable to a Subsidiary Guarantor and to perform
all of the obligations and agreements of a Subsidiary Guarantor under the
Indenture.

      SECTION 2.2. Subsidiary Guarantee. (a) Subsidiary Guarantee. Each
Subsidiary Guarantor hereby fully, unconditionally and irrevocably guarantees,
as primary obligor and not merely as surety, jointly and severally with each
other Subsidiary Guarantor, to each Holder of the Securities and the Trustee the
full and punctual payment when due, whether at maturity, by acceleration, by
redemption or otherwise, of the principal of and interest, including Additional
Amounts, if any, on the Securities and all other obligations and liabilities of
the Parent and the Subsidiary Issuer under the Indenture (including, without
limitation, interest accruing after the filing of any petition in bankruptcy, or
the commencement of any insolvency, reorganization or like proceeding, relating
to the Parent, the Subsidiary Issuer or any Subsidiary Guarantor whether or not
a claim for post-filing or post-petition interest is allowed in such proceeding)
(all the foregoing being hereinafter collectively called the "Obligations").
Each Subsidiary Guarantor further agrees (to the extent permitted by law) that
the Obligations may be extended or renewed, in whole or in part, without notice
or further assent from it, and that it will remain bound under this Section 2.2
hereto notwithstanding any extension or renewal of any Obligation.

      Each Subsidiary Guarantor waives presentation to, demand of payment from
and protest to the Parent or the Subsidiary Issuer of any of the Obligations and
also waives notice of protest for nonpayment. Each Subsidiary Guarantor waives
notice of any default under the Securities or the Obligations. The obligations
of each Subsidiary Guarantor hereunder shall not be affected by (a) the failure
of any Holder to assert any claim or demand or to enforce any right or remedy
against the Parent or the Subsidiary Issuer or any other person under the
Indenture, the Securities or any other agreement or otherwise; (b) any extension
or renewal of any thereof; (c) any rescission, waiver, amendment or modification
of any of the terms or provisions of the Indenture, the Securities or any other
agreement; (d) the release of any security held by any


                                       c-2
<PAGE>
Holder or the Trustee for the Obligations or any of them; (e) the failure of any
Holder to exercise any right or remedy against any other Subsidiary Guarantor;
or (f) any change in the ownership of the Parent or the Subsidiary Issuer.

      Each Subsidiary Guarantor further agrees that its Subsidiary Guarantee
herein constitutes a Guarantee of payment when due (and not a Guarantee of
collection) and waives any right to require that any resort be had by any Holder
to any security held for payment of the Obligations.

      The obligations of each Subsidiary Guarantor hereunder shall not be
subject to any reduction, limitation, impairment or termination for any reason
(other than payment of the Obligations in full), including any claim of waiver,
release, surrender, alteration or compromise, and shall not be subject to any
defense of setoff, counterclaim, recoupment or termination whatsoever or by
reason of the invalidity, illegality or unenforceability of the Obligations or
otherwise. Without limiting the generality of the foregoing, the obligations of
each Subsidiary Guarantor herein shall not be discharged or impaired or
otherwise affected by the failure of any Holder to assert any claim or demand or
to enforce any remedy under the Indenture, the Securities or any other
agreement, by any waiver or modification of any thereof, by any default, failure
or delay, willful or otherwise, in the performance of the Obligations, or by any
other act or thing or omission or delay to do any other act or thing which may
or might in any manner or to any extent vary the risk of any Subsidiary
Guarantor or would otherwise operate as a discharge of such Subsidiary Guarantor
as a matter of law or equity.

      Subject to the provisions of Section 1013, each Subsidiary Guarantor
agrees that its Subsidiary Guarantee herein shall remain in full force and
effect until payment in full of all the Obligations or such Subsidiary Guarantor
is released from its Subsidiary Guarantee upon the merger or the sale of all the
Capital Stock or assets of the Subsidiary Guarantor in compliance with Section
2.2(b) hereto. Each Subsidiary Guarantor further agrees that its Subsidiary
Guarantee herein shall continue to be effective or be reinstated, as the case
may be, if at any time payment, or any part thereof, of principal of or interest
and Additional Amounts, if any, on any of the Obligations is rescinded or must
otherwise be restored by any Holder upon the bankruptcy or reorganization of the
Company or otherwise.

      In furtherance of the foregoing and not in limitation of any other right
which any Holder has at law or in equity against any Subsidiary Guarantor by
virtue hereof, upon the failure of the Company to pay any of the Obligations
when and as the same shall become due, whether at maturity, by acceleration, by
redemption or otherwise, each Subsidiary Guarantor hereby promises to and will,
upon receipt of written demand by the Trustee, forthwith pay, or cause to be
paid, in cash, to the Holders an amount equal to the sum of (i) the unpaid
amount of such Obligations then due and owing and (ii) accrued and unpaid
interest and Additional Amounts, if any, on such Obligations then due and owing
(but only to the extent not prohibited by law).

      Each Subsidiary Guarantor further agrees that, as between such Subsidiary
Guarantor, on the one hand, and the Holders, on the other hand, (x) the maturity
of the Obligations guaranteed hereby may be accelerated as provided in the
Indenture for the purposes of its Subsidiary Guarantee herein, notwithstanding
any stay, injunction or other prohibition preventing such acceleration in
respect of the Obligations guaranteed hereby and (y) in the event


                                       c-3
<PAGE>
of any such declaration of acceleration of such Obligations, such Obligations
(whether or not due and payable) shall forthwith become due and payable by the
Subsidiary Guarantor for the purposes of this Subsidiary Guarantee.

      Each Subsidiary Guarantor also agrees to pay any and all reasonable costs
and expenses (including reasonable attorneys' fees) incurred by the Trustee or
the Holders in enforcing any rights under this Section.

      (b) Limitation on Liability; Termination, Release and Discharge Upon
Merger or Consolidation; Termination on Conversion. (1) The obligations of each
Subsidiary Guarantor hereunder will be limited to the maximum amount as will,
after giving effect to all other contingent and fixed liabilities of such
Subsidiary Guarantor and after giving effect to any collections from or payments
made by or on behalf of any other Subsidiary Guarantor in respect of the
obligations of such other Subsidiary Guarantor under its Subsidiary Guarantee or
pursuant to its contribution obligations under the Indenture, result in the
obligations of such Subsidiary Guarantor under its Subsidiary Guarantee not
constituting a fraudulent conveyance or fraudulent transfer under federal or
state law and not otherwise being void or voidable under any similar laws
affecting the rights of creditors generally.

      (2) Each Subsidiary Guarantor may consolidate with or merge into or sell
its assets to the Company or another Subsidiary Guarantor without limitation.
Subject to Article VIII and Article X of the Indenture, each Subsidiary
Guarantor may consolidate with or merge into or sell all or substantially all
its assets to a corporation, partnership or trust other than the Company or
another Subsidiary Guarantor (whether or not affiliated with the Subsidiary
Guarantor), except that if the surviving corporation of any such merger or
consolidation is a Subsidiary of the Parent or the Subsidiary Issuer, such
merger, consolidation or sale shall not be permitted unless (i) the Person
formed by or surviving any such consolidation or merger assumes all the
obligations of such Subsidiary under the Subsidiary Guarantee pursuant to a
supplemental indenture in form and substance reasonably satisfactory to the
Trustee in respect of the Securities, the Indenture and the Subsidiary
Guarantee, (ii) immediately after giving effect to such transaction, no Default
or Event of Default exists; and (iii) the Parent and the Subsidiary Issuer each
delivers to the Trustee an Officers' Certificate and an Opinion of Counsel
addressed to the Trustee with respect to the foregoing matters. Upon the sale or
disposition of a Subsidiary Guarantor (by merger, consolidation, the sale of its
Capital Stock or the sale of all or substantially all of its assets (other than
by lease)) and whether or not the Subsidiary Guarantor is the surviving
corporation in such transaction to a Person (whether or not an Affiliate of the
Subsidiary Guarantor) which is not the Parent or a Subsidiary of the Parent,
which sale or disposition is otherwise in compliance with the Indenture, such
Subsidiary Guarantor will be released from all its obligations under the
Indenture and its Subsidiary Guarantee and such Subsidiary Guarantee will
terminate.

      (3) Each Subsidiary Guarantor will be deemed released from all its
obligations under the Indenture and its Subsidiary Guarantee and such Subsidiary
Guarantee will terminate upon the discharge of the Securities pursuant to the
provisions of Article IV of the Indenture.

            (c) Right of Contribution. Each Subsidiary Guarantor hereby agrees
that to the extent that any Subsidiary Guarantor shall have paid more than its
proportionate share of any payment made on the obligations under the Subsidiary
Guarantees, such Subsidiary Guarantor


                                       c-4
<PAGE>
shall be entitled to seek and receive contribution from and against the Parent
or the Subsidiary Issuer or any other Subsidiary Guarantor who has not paid its
proportionate share of such payment. The provisions of this Section 2.2(c) shall
in no respect limit the obligations and liabilities of each Subsidiary Guarantor
to the Trustee and the Holders and each Subsidiary Guarantor shall remain liable
to the Trustee and the Holders for the full amount guaranteed by such Subsidiary
Guarantor hereunder.

      (d) No Subrogation. Notwithstanding any payment or payments made by each
Subsidiary Guarantor hereunder, no Subsidiary Guarantor shall be entitled to be
subrogated to any of the rights of the Trustee or any Holder against the Parent
or the Subsidiary Issuer or any other Subsidiary Guarantor or any collateral
security or guarantee or right of offset held by the Trustee or any Holder for
the payment of the Obligations, nor shall any Subsidiary Guarantor seek or be
entitled to seek any contribution or reimbursement from the Company or any other
Subsidiary Guarantor in respect of payments made by such Subsidiary Guarantor
hereunder, until all amounts owing to the Trustee and the Holders by the Company
on account of the Obligations are paid in full. If any amount shall be paid to
any Subsidiary Guarantor on account of such subrogation rights at any time when
all of the Obligations shall not have been paid in full, such amount shall be
held by such Subsidiary Guarantor in trust for the Trustee and the Holders,
segregated from other funds of such Subsidiary Guarantor, and shall, forthwith
upon receipt by such Subsidiary Guarantor, be turned over to the Trustee in the
exact form received by such Subsidiary Guarantor (duly indorsed by such
Subsidiary Guarantor to the Trustee, if required), to be applied against the
Obligations.


                                   ARTICLE III

                                  Miscellaneous

      SECTION 3.1. Notices. All notices and other communications to the
Guarantor shall be given as provided in the Indenture to the Guarantor, at its
address set forth below, with a copy to the Parent and the Subsidiary Issuer as
provided in the Indenture for notices to the Parent and the Subsidiary Issuer.

      SECTION 3.2. Parties. Nothing expressed or mentioned herein is intended or
shall be construed to give any Person, firm or corporation, other than the
Holders and the Trustee, any legal or equitable right, remedy or claim under or
in respect of this Supplemental Indenture or the Indenture or any provision
herein or therein contained.

      SECTION 3.3. Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED
BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.


                                       c-5
<PAGE>
      SECTION 3.4. Severability Clause. In case any provision in this
Supplemental Indenture shall be invalid, illegal or unenforceable, the validity,
legality and enforceability of the remaining provisions shall not in any way be
affected or impaired thereby and such provision shall be ineffective only to the
extent of such invalidity, illegality or unenforceability.

      SECTION 3.5. Ratification of Indenture; Supplemental Indentures Part of
Indenture. Except as expressly amended hereby, the Indenture is in all respects
ratified and confirmed and all the terms, conditions and provisions thereof
shall remain in full force and effect. This Supplemental Indenture shall form a
part of the Indenture for all purposes, and every Holder of Securities
heretofore or hereafter authenticated and delivered shall be bound hereby. The
Trustee makes no representation or warranty as to the validity or sufficiency of
this Supplemental Indenture.

      SECTION 3.6. Counterparts. The parties hereto may sign one or more copies
of this Supplemental Indenture in counterparts, all of which together shall
constitute one and the same agreement.

      SECTION 3.7. Headings. The headings of the Articles and the sections in
this Guarantee are for convenience of reference only and shall not be deemed to
alter or affect the meaning or interpretation of any provisions hereof.



            IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed as of the date first above written.

                                     [SUBSIDIARY GUARANTOR],
                                     as a Guarantor



                                     By:_______________________________________
                                           Name:
                                           Title:


                                     U.S. BANK NATIONAL ASSOCIATION, as Trustee



                                     By:_______________________________________


                                       c-6
<PAGE>
                                           Name:
                                           Title:


                                     TOM BROWN, INC.



                                     By:_______________________________________
                                           Name:
                                           Title:


                                     TOM BROWN RESOURCES FUNDING CORP.



                                     By:_______________________________________
                                           Name:
                                           Title:


                                     [INSERT OTHER SUBSIDIARY GUARANTORS]



                                     By:_______________________________________
                                           Name:



                                       c-7