<PAGE>   1
                                                                    Exhibit 4.1


                             KERR-McGEE CORPORATION



                                       TO



                            CITIBANK, N.A., Trustee



                                    INDENTURE



                           DATED AS OF AUGUST __, 2001
<PAGE>   2
                             KERR-McGEE CORPORATION
         Reconciliation and tie between Trust Indenture Act of 1939 and
                     Indenture, dated as of August __, 2001

<TABLE>
<CAPTION>
TRUST INDENTURE ACT SECTION                                          INDENTURE SECTION
---------------------------                                          -----------------
<S>                                                                  <C>
Section 310 (a)(1) ..........................................          609
       (a)(2) ...............................................          609
       (a)(3) ...............................................          Not Applicable
       (a)(4) ...............................................          Not Applicable
       (b) ..................................................          608
                                                                       610
Section 311 (a) .............................................          613(a)
       (b) ..................................................          613(b)
       (b)(2) ...............................................          703(a)(2)
                                                                       703(b)
Section 312 (a) .............................................          701
                                                                       702(a)
       (b) ..................................................          702(b)
       (c) ..................................................          702(c)
Section 313 (a) .............................................          703(a)
       (b) ..................................................          703(b)
       (c) ..................................................          703(a),703(b)
       (d) ..................................................          703(c)
Section 314 (a) .............................................          704
       (c)(1) ...............................................          102
       (c)(2) ...............................................          102
       (c)(3) ...............................................          Not Applicable
       (d) ..................................................          Not Applicable
       (e) ..................................................          102
Section 315 (a) .............................................          601(a)
       (b) ..................................................          602
                                                                       703(a)(6)
       (c) ..................................................          601(b)
       (d) ..................................................          601(c)
       (d)(1) ...............................................          601(a)(1)
       (d)(2) ...............................................          601(c)(2)
       (d)(3) ...............................................          601(c)(3)
       (e) ..................................................          509
Section 316 (a) .............................................          101
       (a)(1)(A) ............................................          502
                                                                       508
       (a)(1)(B) ............................................          508
       (a)(2) ...............................................          Not Applicable
       (b) ..................................................          505
Section 317 (a)(1) ..........................................          503
       (a)(2) ...............................................          503
       (b) ..................................................         1003
Section 318 (a) .............................................          107
</TABLE>

----------

      Note: This reconciliation and tie shall not, for any purpose, be deemed to
be a part of the Indenture.
<PAGE>   3
                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
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<S>                                                                                                                  <C>
PARTIES..........................................................................................................       1
RECITALS.........................................................................................................       1

ARTICLE ONE    DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATIONS..........................................       1

         Section 1.01. Definitions...............................................................................       1
         "Act"    ...............................................................................................       2
         "Affiliate".............................................................................................       2
         "Authenticating Agent"..................................................................................       2
         "Board of Directors"....................................................................................       2
         "Board Resolution"......................................................................................       2
         "Business Day"..........................................................................................       2
         "Commission"............................................................................................       2
         "Company"...............................................................................................       3
         "Company Request" and "Company Order"...................................................................       3
         "Consolidated Net Tangible Assets"......................................................................       3
         "Corporate Trust Office"................................................................................       3
         "Covenant Defeasance Option"............................................................................       3
         "Defaulted Interest"....................................................................................       3
         "Discharged"............................................................................................       3
         "Eligible Guarantors"...................................................................................       4
         "Event of Default"......................................................................................       4
         "Funded Debt"...........................................................................................       4
         "Global Security".......................................................................................       4
         "Guarantee".............................................................................................       4
         "Guarantor".............................................................................................       4
         "Holder" 4
         "Indenture".............................................................................................       4
         "interest"..............................................................................................       5
         "Interest Payment Date".................................................................................       5
         "Legal Defeasance Option"...............................................................................       5
         "Maturity"..............................................................................................       5
         "Officers' Certificate".................................................................................       5
         "Opinion of Counsel"....................................................................................       5
         "Original Issue Discount Security"......................................................................       5
         "Outstanding"...........................................................................................       5
         "Paying Agent"..........................................................................................       6
         "Person"................................................................................................       6
         "Predecessor Security"..................................................................................       6
         "Principal Property"....................................................................................       7
         "Redemption Date".......................................................................................       7
</TABLE>


                                       i
<PAGE>   4
<TABLE>
<CAPTION>
                                                                                                                     PAGE
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<S>                                                                                                                  <C>
         "Redemption Price"......................................................................................       7
         "Regular Record Date"...................................................................................       7
         "Responsible Officer"...................................................................................       7
         "Restricted Subsidiary".................................................................................       7
         "Securities"............................................................................................       8
         "Security Register" and "Security Registrar"............................................................       8
         "Special Record Date"...................................................................................       8
         "Stated Maturity".......................................................................................       8
         "Stockholders' Equity"..................................................................................       8
         "Subsidiary"............................................................................................       8
         "Trustee"...............................................................................................       8
         "Trust Indenture Act"...................................................................................       9
         "United States".........................................................................................       9
         "U.S. Depositary".......................................................................................       9
         "U.S. Government Obligations"...........................................................................       9
         "Voting Stock"..........................................................................................       9
         "Yield to Maturity".....................................................................................       9
         Section 1.02. Compliance Certificates and Opinions......................................................       9
         Section 1.03. Form of Documents Delivered to Trustee....................................................      10
         Section 1.04. Acts of Holders...........................................................................      10
         Section 1.05. Notices, etc., to Trustee and Company.....................................................      11
         Section 1.06. Notice to Holders; Waiver.................................................................      12
         Section 1.07. Conflict with Trust Indenture Act.........................................................      12
         Section 1.08. Effect of Headings and Table of Contents..................................................      12
         Section 1.09. Successors and Assigns....................................................................      12
         Section 1.10. Separability Clause.......................................................................      13
         Section 1.11. Benefits of Indenture.....................................................................      13
         Section 1.12. Governing Law.............................................................................      13
         Section 1.13. Legal Holidays............................................................................      13
         Section 1.14. Indenture and Securities Solely Corporate Obligations.....................................      13
         Section 1.15. No Security Interest Created..............................................................      13

ARTICLE TWO    SECURITY FORMS....................................................................................      14

         Section 2.01. Forms Generally...........................................................................      14
         Section 2.02. Form of Trustee's Certificate of Authentication...........................................      14
         Section 2.03. Securities in Global Form.................................................................      14

ARTICLE THREE    THE SECURITIES..................................................................................      15

         Section 3.01. Amount Unlimited; Issuable in Series......................................................      15
         Section 3.02. Denominations.............................................................................      17
         Section 3.03. Authentication and Dating.................................................................      17
         Section 3.04. Execution of Securities...................................................................      18
         Section 3.05. Exchange and Registration of Transfer of Securities.......................................      18
         Section 3.06. Mutilated, Destroyed, Lost or Stolen Securities...........................................      19
</TABLE>


                                       ii
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<TABLE>
<CAPTION>
                                                                                                                     PAGE
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         Section 3.07. Temporary Securities......................................................................      20
         Section 3.08. Payment of Interest; Interest Rights Preserved............................................      22
         Section 3.09. Persons Deemed Owners.....................................................................      23
         Section 3.10. Cancellation..............................................................................      23
         Section 3.11. Computation of Interest...................................................................      23
         Section 3.12. CUSIP Numbers.............................................................................      24

ARTICLE FOUR    SATISFACTION AND DISCHARGE.......................................................................      24

         Section 4.01. Satisfaction and Discharge of Indenture...................................................      24
         Section 4.02. Application of Trust Money................................................................      25

ARTICLE FIVE    REMEDIES ........................................................................................      25

         Section 5.01. Events of Default.........................................................................      25
         Section 5.02. Acceleration of Maturity; Rescission and Annulment........................................      26
         Section 5.03. Payment of Securities on Default; Suit Therefor...........................................      27
         Section 5.04. Application of Moneys Collected by Trustee................................................      29
         Section 5.05. Proceedings by Holders....................................................................      30
         Section 5.06. Proceedings by Trustee....................................................................      30
         Section 5.07. Remedies Cumulative and Continuing........................................................      30
         Section 5.08. Direction of Proceedings and Waiver of Defaults by Majority of Holders....................      31
         Section 5.09. Undertaking to Pay Costs..................................................................      31

ARTICLE SIX    THE TRUSTEE ......................................................................................      32

         Section 6.01. Certain Duties and Responsibilities.......................................................      32
         Section 6.02. Notice of Defaults........................................................................      33
         Section 6.03. Certain Rights of Trustee.................................................................      33
         Section 6.04. Not Responsible for Recitals or Issuance of Securities....................................      34
         Section 6.05. May Hold Securities.......................................................................      35
         Section 6.06. Money Held in Trust.......................................................................      35
         Section 6.07. Compensation and Reimbursement............................................................      35
         Section 6.08. Disqualification; Conflicting Interests...................................................      36
         Section 6.09. Corporate Trustee Required; Eligibility...................................................      36
         Section 6.10. Resignation and Removal; Appointment of Successor.........................................      36
         Section 6.11. Acceptance of Appointment by Successor....................................................      38
         Section 6.12. Merger, Conversion, Consolidation or Succession to Business...............................      39
         Section 6.13. Preferential Collection of Claims Against Company.........................................      39
         Section 6.14. Appointment of Authenticating Agent.......................................................      43

ARTICLE SEVEN    HOLDER'S LISTS AND REPORTS BY TRUSTEE AND COMPANY...............................................      44

         Section 7.01. Company to Furnish Trustee Names and Addresses of Holders.................................      44
         Section 7.02. Preservation of Information:  Communications to Holders...................................      45
</TABLE>


                                   iii
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<TABLE>
<CAPTION>
                                                                                                                     PAGE
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<S>                                                                                                                  <C>
         Section 7.03. Reports by Trustee........................................................................      46
         Section 7.04. Reports by Company........................................................................      47

ARTICLE EIGHT    CONSOLIDATION, MERGER, SALE, CONVEYANCE OR LEASE................................................      48

         Section 8.01. Consolidations and Mergers of Company and Conveyances Permitted Subject to Certain
                               Conditions........................................................................      48
         Section 8.02. Rights and Duties of Successor Corporation................................................      48
         Section 8.03. Securities to be secured in Certain Events................................................      49
         Section 8.04. Officers' Certificate and Opinion of Counsel..............................................      49
         Section 8.05. Limitation on Lease of Properties as Entirety.............................................      49

ARTICLE NINE    SUPPLEMENTAL INDENTURES..........................................................................      50

         Section 9.01. Supplemental Indentures without Consent of Holders........................................      50
         Section 9.02. Supplemental Indentures with Consent of Holders...........................................      51
         Section 9.03. Compliance with Trust Indenture Act; Effect of Supplemental Indentures....................      52
         Section 9.04. Notation on Securities....................................................................      52
         Section 9.05. Evidence of Compliance of Supplemental Indenture to be Furnished Trustee..................      52

ARTICLE TEN    COVENANTS ........................................................................................      53

         Section 10.01. Payment of Principal and Interest........................................................      53
         Section 10.02. Maintenance of Office or Agency..........................................................      53
         Section 10.03. Money for Security Payments to be Held in Trust..........................................      53
         Section 10.04. Payment of Taxes and Other Claims........................................................      54
         Section 10.05. Maintenance of Principal Properties......................................................      55
         Section 10.06. Statement as to Default..................................................................      55
         Section 10.07. Corporate Existence......................................................................      55
         Section 10.08. Limitation on Secured Debt...............................................................      56
         Section 10.09. Limitation on Sales and Leasebacks.......................................................      57
         Section 10.10. Waiver of Certain Covenants..............................................................      58
         Section 10.11. Calculation of Original Issue Discount...................................................      58

ARTICLE ELEVEN    REDEMPTION OF SECURITIES.......................................................................      58

         Section 11.01. Applicability of Article.................................................................      58
         Section 11.02. Notice of Redemption; Selection of Securities............................................      59
         Section 11.03. Payment of Securities Called for Redemption..............................................      59

ARTICLE TWELVE    SINKING FUNDS..................................................................................      60

         Section 12.01. Applicability of Article.................................................................      60
         Section 12.02. Satisfaction of Mandatory Sinking Fund Payments with Securities..........................      60
</TABLE>


                                       iv
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<TABLE>
<CAPTION>
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<S>                                                                                                                  <C>
         Section 12.03. Redemption of Securities for Sinking Fund................................................      60

ARTICLE THIRTEEN    HOLDERS' MEETINGS............................................................................      62

         Section 13.01. Purposes of Meetings.....................................................................      62
         Section 13.02. Call of Meetings by Trustee..............................................................      62
         Section 13.03. Call of Meetings by Company or Holders...................................................      62
         Section 13.04. Qualifications for Voting................................................................      63
         Section 13.05. Regulations..............................................................................      63
         Section 13.06. Voting 64
         Section 13.07. Revocation by Holders....................................................................      64
         Section 13.08. No Delay.................................................................................      65
         Section 13.09. Action by Holders........................................................................      65

ARTICLE FOURTEEN    DEFEASANCE...................................................................................      65

         Section 14.01. Applicability of Article.................................................................      65
         Section 14.02. Defeasance Upon Deposit of Moneys or U.S. Government Obligations.........................      66
         Section 14.03. Deposited Moneys and U.S. Government Obligations to Be Held in Trust.....................      67
         Section 14.04. Repayment to Company.....................................................................      67

ARTICLE FIFTEEN    GUARANTEES....................................................................................      68

         Section 15.01. Guarantees...............................................................................      68
         Section 15.02. Obligations of the Guarantor Unconditional...............................................      69
         Section 15.03. Article Fifteen Not To Prevent Events of Default.........................................      70
         Section 15.04. Execution and Delivery of Guarantee......................................................      70

TESTIMONIUM......................................................................................................      62
SIGNATURES AND SEALS.............................................................................................      63
ACKNOWLEDGEMENTS.................................................................................................      64
EXHIBIT A........................................................................................................      65
</TABLE>


                                       v
<PAGE>   8
         INDENTURE, dated as of August __, 2001 between KERR-McGEE Corporation,
a Delaware corporation (hereinafter called the "Company"), and Citibank, N.A., a
national banking association incorporated and existing under the laws of the
United States of America (hereinafter called the "Trustee").

                             RECITALS OF THE COMPANY

         The Company has duly authorized the execution and delivery of this
Indenture to provide for the issuance from time to time of its unsecured
debentures, notes or other evidences of indebtedness to be issued in one or more
series (herein called the "Securities"), as in this Indenture provided, up to
such principal amount or amounts as may from time to time be authorized in or
pursuant to one or more Board Resolutions.

         All things necessary to make this Indenture a valid and legally binding
agreement of the Company, in accordance with its terms, have been done.

         NOW, THEREFORE, THIS INDENTURE WITNESSETH:

         For and in consideration of the premises and the purchase of the
Securities by the Holders thereof, it is mutually covenanted and agreed, for the
equal and proportionate benefit of all Holders of the Securities or of series
thereof, as follows:

                                   ARTICLE ONE

                        DEFINITIONS AND OTHER PROVISIONS
                             OF GENERAL APPLICATION

         Section 1.01.     Definitions.

         For all purposes of this Indenture, except as otherwise expressly
provided or unless the context otherwise requires:

                  (1) the terms defined in this Article have the meanings
         assigned to them in this Article, and include the plural as well as the
         singular;

                  (2) all other terms used herein which are defined in the Trust
         Indenture Act, either directly or by reference therein, have the
         meanings assigned to them therein;

                  (3) all accounting terms not otherwise defined herein have the
         meanings assigned to them in accordance with generally accepted
         accounting principles, and the term "generally accepted accounting
         principles" with respect to any computation required or permitted
         hereunder shall mean such accounting principles which are generally
         accepted at the date or time of such computation; and

                  (4) the words "herein", "hereof" and "hereunder" and other
         words of similar import refer to this Indenture as a whole and not to
         any particular Article, Section or other subdivision.
<PAGE>   9
                                                                               2
         Certain terms, used principally in Article Six, are defined in that
Article.

         "Act" when used with respect to any Holder has the meaning specified in
Section 1.04.

         "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 specified 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.

         "Authenticating Agent" means any authenticating agent appointed by the
Trustee pursuant to Section 6.14.

         "Board of Directors" means the board of directors of the Company or any
duly authorized committee of that board or any director or directors and/or
officer or officers of the Company to whom that board or committee shall have
duly delegated its authority.

         "Board Resolution" means (1) a copy of a resolution certified by the
Secretary or an Assistant Secretary of the Company to have been duly adopted by
the Board of Directors and to be in full force and effect on the date of such
certification, or (2) a certificate signed by the director or directors and/or
officer or officers to whom the Board of Directors or any duly authorized
committee of that board shall have duly delegated its authority, in each case
delivered to the Trustee for the Securities of any series.

         "Business Day" means each Monday, Tuesday, Wednesday, Thursday and
Friday which is not a day on which banking institutions in The City of New York
are authorized or required by law or executive order to be closed.

         "Commission" means the Securities and Exchange Commission, as from time
to time constituted, created under the Securities Exchange Act of 1934, or if at
any time after the execution of this instrument such Commission is not existing
and performing the duties now assigned to it under the Trust Indenture Act, then
the body performing such duties on such date.

         "Company" means the Person named as the "Company" in the first
paragraph of this instrument until a successor corporation shall have become
such pursuant to the applicable provisions of this Indenture, and thereafter
"Company" shall mean such successor corporation.

         "Company Request" and "Company Order" mean, respectively, a written
request or order signed in the name of the Company by the Chairman or Vice
Chairman of the Board, the President or a Vice President (any reference to a
Vice President of the Company herein shall be deemed to include any Vice
President of the Company whether or not designated by a number or a word or
words added before or after the title "Vice President"), and by the Treasurer,
an Assistant Treasurer, the Controller, an Assistant Controller, the Secretary
or an Assistant Secretary of the Company, and delivered to the Trustee.

         "Consolidated Net Tangible Assets" will be defined as the aggregate
amount of assets included on a consolidated balance sheet of the Company and its
Restricted Subsidiaries, less
<PAGE>   10
                                                                               3


applicable reserves and other properly deductible items and after deducting
therefrom (a) all current liabilities and (b) all goodwill, trade names,
trademarks, patents, unamortized debt discount and expense and other like
intangibles, all in accordance with generally accepted accounting principles
consistently applied.

         "Corporate Trust Office" of the Trustee means the principal corporate
trust office of the Trustee at which at any particular time its corporate trust
business shall be principally administered, which office as of the date hereof
is located at 111 Wall Street, 14th Floor, New York, NY 10005, Attn: Citibank
Agency & Trust.

         "Covenant Defeasance Option" has the meaning specified in Section
14.02.

         "Defaulted Interest" has the meaning specified in Section 3.08.

         "Discharged" has the meaning specified in Section 14.02.

         "Eligible Guarantors" means Kerr-McGee Operating Corporation, a
Delaware corporation, and HS Resources, Inc., a Delaware corporation.

         "Event of Default" has the meaning specified in Article Five.

         "Funded Debt" means all indebtedness for money borrowed, or evidenced
by a bond, debenture, note or similar instrument or agreement whether or not for
money borrowed, having a maturity of more than 12 months from the date as of
which the amount thereof is being determined or having a maturity of less than
12 months but by its terms being renewable or extendible beyond 12 months from
such date at the option of the borrower.

         "Global Security" means a Security evidencing all or part of a series
of Securities, including, without limitation, any temporary or permanent Global
Securities.

         "Guarantee" has the meaning specified in Section 15.01.

         "Guarantor" has the meaning specified in Section 3.01.

         "Holder" means a Person in whose name a Security is registered in the
Security Register.

         "Indenture" means this instrument as originally executed or as it may
from time to time be supplemented or amended by one or more indentures
supplemental hereto entered into pursuant to the applicable provisions hereof,
and shall include the form and terms of particular series of Securities
established as contemplated hereunder; provided, however, that if at any time
more than one Person is acting as Trustee under this instrument, "Indenture"
shall mean with respect to any one or more series of Securities for which such
Person is Trustee, this instrument as originally executed or as it may from time
to time be supplemented or amended by one or more indentures supplemental hereto
entered into pursuant to the applicable provisions hereof and shall include the
terms of particular series of Securities for which such person is Trustee
established as contemplated by Section 3.01, exclusive, however, of any
provisions or terms which relate solely to other series of Securities for which
such Person is not Trustee, regardless of when such terms or provisions were
adopted, and exclusive of any provisions or terms
<PAGE>   11
                                                                               4


adopted by means of one or more indentures supplemental hereto executed and
delivered after such Person had become such Trustee but to which such Person, as
such Trustee, was not a party.

         "interest" when used with respect to non-interest bearing Securities
means interest payable after Maturity.

         "Interest Payment Date" means the Stated Maturity of an installment of
interest on the Security (in the case of an interest-bearing Security).

         "Legal Defeasance Option" has the meaning specified in Section 14.02.

         "Maturity" when used with respect to any Security means the date on
which the principal of such Security becomes due and payable as therein or
herein provided, whether at the Stated Maturity or by declaration of
acceleration, call for redemption or otherwise.

         "Officers' Certificate" means a certificate signed by the Chairman or
Vice Chairman of the Board, the President or a Vice President, and by the
Treasurer, an Assistant Treasurer, the Controller, an Assistant Controller, the
Secretary or an Assistant Secretary of the Company, and delivered to the
Trustee.

         "Opinion of Counsel" means a written opinion of counsel, who may
(except as otherwise expressly provided in this Indenture) be counsel for the
Company.

         "Original Issue Discount Security" means any Security which provides
for an amount less than the principal amount thereof to be due and payable upon
a declaration of acceleration of the maturity thereof pursuant to Section 5.02.

         "Outstanding" when used with respect to Securities means, as of the
date of determination, all Securities theretofore authenticated and delivered
under this Indenture, except:

                  (i) Securities theretofore cancelled by the Trustee or
         delivered to the Trustee for cancellation;

                  (ii) Securities for whose payment or redemption money in the
         necessary amount has been theretofore deposited with the Trustee or any
         Paying Agent (other than the Company) in trust or set aside and
         aggregated in trust by the Company (if the Company shall act as its own
         Paying Agent, for the Holders of such Securities, provided that, if
         such Securities are to be redeemed, notice of such redemption has been
         duly given pursuant to this Indenture or provision therefor
         satisfactory to the Trustee has been made; and

                  (iii) Securities in exchange for or in lieu of which other
         Securities have been authenticated and delivered pursuant to this
         Indenture;

provided, however, that in determining whether the Holders of the requisite
principal amount of Outstanding Securities have given any request, demand,
authorization, direction, notice, consent or waiver hereunder, Securities owned
by the Company or any other obligor upon the Securities or any Affiliate of the
Company or such other obligor shall be disregarded and deemed not to be
<PAGE>   12
                                                                               5


Outstanding, except that, in determining whether the Trustee shall be protected
in relying upon any such request, demand, authorization, direction, notice,
consent or waiver, only Securities which a Responsible Officer of the Trustee
actually knows to be so owned shall be so disregarded. Securities so owned which
have been pledged in good faith may be regarded as Outstanding if the pledgee
established to the satisfaction of the Trustee the pledgee's right so to act
with respect to such Securities and that the pledgee is not the Company or any
other obligor upon the Securities or any Affiliate of the Company or such other
obligor.

         In determining whether the Holders of the requisite principal amount of
Outstanding Securities have given any request, demand, authorization, direction,
notice, consent or waiver hereunder the principal amount of an Original Issue
Discount Security that shall be deemed to be Outstanding for such purpose shall
be the amount of the principal thereof that would be due and payable as of the
date of such determination upon a declaration of the acceleration of the
maturity thereof pursuant to Section 5.02.

         "Paying Agent" means any Person authorized by the Company to pay the
principal of (or premium, if any) or interest on any Securities on behalf of the
Company.

         "Person" means any individual, corporation, partnership, joint venture,
association, joint-stock company, trust, unincorporated organization or
government or any agency or political subdivision thereof.

         "Predecessor Security" of any particular Security means every previous
Security evidencing all or a portion of the same debt as that evidenced by such
particular Security; and for the purposes of this definition, any Security
authenticated and delivered under Section 3.06 in lieu of a lost, destroyed or
stolen Security shall be deemed to evidence the same debt as the lost, destroyed
or stolen Security.

         "Principal Property" means any mineral producing property capable of
producing minerals in paying quantities and any manufacturing or refining plant
(together with the land upon which it is erected and fixtures comprising a part
thereof) located in the continental United States owned by the Company or any
Restricted Subsidiary, whether now owned or hereafter acquired (other than any
facility hereafter acquired for the control or abatement of atmospheric
pollutants or contaminants, water pollution, noise, odor or other pollution or
otherwise financed through the issuance of industrial revenue bonds or similar
types of financing) other than any such property or plant which, in the opinion
of the Board of Directors of the Company, is not of material importance to the
total business conducted by the Company and its Subsidiaries as a whole.

         "Redemption Date" when used with respect to any Security to be redeemed
means the date fixed for such redemption by or pursuant to the Board Resolution
establishing the series of Securities of which the Security to be redeemed is a
member.

         "Redemption Price" when used with respect to any Security to be
redeemed means the price at which it is to be redeemed pursuant to the Board
Resolution establishing the series of Securities of which the Security to be
redeemed is a member.
<PAGE>   13
                                                                               6


         "Regular Record Date" for the interest payable on any Interest Payment
Date (in the case of an interest-bearing Security) means such date or dates as
may be fixed for such purpose in the Board Resolution establishing the series of
Securities of which the Security is a member.

         "Responsible Officer" when used with respect to 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"), any Senior Trust Officer, any Trust
Officer or Assistant Trust Officer or any other officer or assistant officer of
the Trustee customarily performing functions similar to those performed by any
of the above-designated officers and also means, with respect to a particular
corporate trust matter, any other officer or assistant officer to whom such
matter is referred because of his knowledge of and familiarity with the
particular subject and who shall have direct responsibility for the
administration of this Indenture.

         "Restricted Subsidiary" means any Subsidiary (a) which is designated a
Restricted Subsidiary by resolution of the Board of Directors, or (b) which owns
or leases any Principal Property, except that such term shall exclude any
Subsidiary the principal business of which is leasing assets, financing the sale
of products or holding the securities of other Subsidiaries.

         "Securities" has the meaning stated in the first recital of this
Indenture and more particularly means any Securities authenticated and delivered
under this Indenture; provided, however, that if at any time there is more than
one Person acting as Trustee under this instrument, "Securities" with respect to
the Indenture as to which such Person is Trustee shall have the meaning stated
in the first recital of this instrument and shall more particularly mean
Securities authenticated and delivered under this instrument, exclusive, however
of Securities of any series as to which such Person is not Trustee.

         "Security Register" and "Security Registrar", have the meanings
specified in Section 3.05.

         "Special Record Date" for the payment of any Defaulted Interest means a
date fixed by the Trustee pursuant to Section 3.08.

         "Stated Maturity" when used with respect to any Security or any
installment of interest thereon means the date specified in such Security as the
fixed date on which the principal of such Security or such installment of
interest is due and payable.

         "Stockholders' Equity" means as of any particular time the aggregate of
capital, surplus and retained earnings of the Company and its consolidated
Subsidiaries, as shown in the most recent consolidated financial statements of
the Company and its consolidated Subsidiaries (including investments in and
advances to others, made by the Company and/or by one or more consolidated
Subsidiaries, at not more than cost), prepared in accordance with generally
accepted accounting principles.

         "Subsidiary" means a corporation at least a majority of the outstanding
Voting Stock of which is owned, directly or indirectly, by the Company or by one
or more Subsidiaries of the Company, or by the Company and one or more
Subsidiaries of the Company.
<PAGE>   14
                                                                               7


         "Trustee" means the Person named as the "Trustee" in the first
paragraph of this instrument until a successor Trustee shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Trustee" shall mean such successor Trustee; provided, however, that if at any
time there is more than one such person, "Trustee" as used with respect to the
Securities of any series shall mean only the Trustee with respect to Securities
of that series.

         "Trust Indenture Act" means the Trust Indenture Act of 1939, as amended
by the Trust Indenture Reform Act of 1990, as in force at the date as of which
this instrument was executed, except as provided in Section 9.03.

         "United States" means the United States excluding its territories and
possessions.

         "U.S. Depositary" means a clearing agency registered under the
Securities Exchange Act of 1934, as amended, or any successor thereto, which
shall in either case be designated by the Corporation pursuant to Section 3.01,
until a successor U.S. Depositary shall have become such pursuant to the
applicable provisions of this Indenture, and thereafter "U.S. Depositary" shall
mean or include each Person who is then a U.S. Depositary hereunder, and if at
any time there is more than one such Person, "U.S. Depositary" as used with
respect to the Securities of any series shall mean the U.S. Depositary with
respect to the Securities of that series.

         "U.S. Government Obligations" has the meaning specified in Section
14.02.

         "Voting Stock" of a corporation means stock of the class or classes
having general voting power under ordinary circumstances to elect at least a
majority of the board of directors, managers or trustees of such corporation
(irrespective of whether or not at the time stock of any other class or classes
shall have or might have voting power by reason of the happening of any
contingency).

         "Yield to Maturity" means the yield to maturity, calculated at the time
of issuance of a series of Securities or, if applicable, at the most recent
redetermination of interest on such series and calculated in accordance with
accepted financial practice.

         Section 1.02.     Compliance Certificates and Opinions.

                  Upon any application or request by the Company to the Trustee
to take any action under any provision of this Indenture, the Company shall
furnish to the Trustee an Officers' Certificate stating that all conditions
precedent, if any, provided for in this Indenture relating to the proposed
action have been complied with and an Opinion of Counsel stating that in the
opinion of such counsel all such conditions precedent, if any, have been
complied with, except that in the case of any such application or request as to
which the furnishing of such documents is specifically required by any provision
of this Indenture relating to such particular application or request, no
additional certificate or opinion need be furnished.

         Every certificate (other than certificates provided pursuant to Section
10.06) or opinion with respect to compliance with a condition or covenant
provided for in this Indenture shall include
<PAGE>   15
                                                                               8


            (1) a statement that each individual signing such certificate or
      opinion has read such covenant or condition and the definitions herein
      relating thereto;

            (2) a brief statement as to the nature and scope of the examination
      or investigation upon which the statements or opinions contained in such
      certificate or opinion are based;

            (3) a statement that, in the opinion of each such individual, he has
      made such examination or investigation as is necessary to enable him to
      express an informed opinion as to whether or not such covenant or
      condition has been complied with; and

            (4) a statement as to whether, in the opinion of each such
      individual, such condition or covenant has been complied with.

      Section 1.03.     Form of Documents Delivered to Trustee.

      In any case where several matters are required to be certified by, or
covered by an opinion of, any specified Person, it is not necessary that all
such matters be certified by, or covered by the opinion of, only one such
Person, or that they be so certified or covered by only one document, but one
such Person may certify or give an opinion with respect to some matters and one
or more other such Persons as to other matters, and any such Person may
certified or give an opinion as to such matters in one or several documents.

      Any certificate or opinion of an officer of the Company may be based,
insofar as it relates to legal matters, upon a certificate of opinion of, or
representations by, counsel, unless such officer knows, or in the exercise of
reasonable care should know, that the certificate or opinion or representations
with respect to matters upon which his certificate or opinion is based are
erroneous. Any such certificate or Opinion of Counsel may be based, insofar as
it relates to factual matters, upon a certificate or opinion of, or
representations by, an officer or officers of the Company stating that the
information with respect to such factual matters is in the possession of the
Company, unless such counsel knows, or in the exercise of reasonable care should
know, that the certificate or opinion or representations with respect to such
matters are erroneous.

      Where any Person is required to make, give or execute two or more
applications, requests, consents, certificates, statements, opinions or other
instruments under this Indenture, they may, but need not, be consolidated and
form one instrument.

      Section 1.04.     Acts of Holders.

      (a) Any request, demand, authorization, direction, notice, consent, waiver
or other action provided by this Indenture to be given or taken by Holders may
be embodied in and evidenced by one or more instruments of substantially similar
tenor signed by such Holders in person or by agent duly appointed in writing;
and, except as herein otherwise expressly provided, such action shall become
effective when such instrument or instruments are delivered to the Trustee, and,
where it is hereby expressly required, to the Company. Such instrument or
instruments (and the action embodied therein and evidenced thereby) are herein
sometimes referred to as the "Act" of the Holders signing such instrument or
instruments. Proof of execution of any such instrument or of a writing
appointing any such agent shall be sufficient for
<PAGE>   16
                                                                               9


any purpose of this Indenture and (subject to Section 6.01) conclusive in favor
of the Trustee and the Company and any agent of the Trustee or the Company, if
made in the manner provided in this Section.

      (b) The fact and date of the execution by any Person of any such
instrument or writing may be proved by the affidavit of a witness of such
execution or by the certificate of any notary public or other officer authorized
by law to take acknowledgments of deeds, certifying that the individual signing
such instrument or writing acknowledged to him the execution thereof. Where such
execution is by an officer of a corporation or association or a member of a
partnership or an official of a public or governmental body, on behalf of such
corporate, association, partnership, or public or governmental body or by a
fiduciary, such certificate or affidavit shall also constitute sufficient proof
of his authority. The fact and date of the execution by any Person of any such
instrument or writing, or the authority of the Person executing the same, may
also be proved in any other manner which the Trustee deems sufficient and in
accordance with such reasonable rules as the Trustee may determine.

      (c) The ownership of Securities shall be proved by the Security Register.

      (d) Any request, demand, authorization, direction, notice, consent, waiver
or other action by the Holder of any Security shall bind every future Holder of
the same Security and the Holder of every Security issued upon the transfer
thereof or in exchange therefor or in lieu thereof in respect of anything done
or suffered to be done by the Trustee, any Security Registrar, any Paying Agent,
any Authenticating Agent or the Company in reliance thereon, whether or not
notation of such action is made upon such Securities.

      Section 1.05.     Notices, etc., to Trustee and Company.

      Any request, demand, authorization, direction, notice, consent, waiver or
Act of Holders or other document provided or permitted by this Indenture to be
made upon, given or furnished to, or filed with,

            (1) the Trustee by any Holder or by the Company shall be sufficient
      for every purpose hereunder if in writing and mailed, first-class postage
      prepaid, to the Trustee addressed to it at its Corporate Trust Office;

            (2) the Company by the Trustee or by any Holder shall be sufficient
      for every purpose hereunder if in writing and mailed, first-class postage
      prepaid, to the Company addressed to it at Kerr-McGee Center, Oklahoma
      City, Oklahoma 73102, Attention: Secretary, or at any other address
      previously furnished in writing to the Trustee by the Company.

      Section 1.06.     Notice to Holders; Waiver.

      Where this Indenture provides for notice to Holders of any event, such
notice shall be sufficiently given (unless otherwise herein expressly provided)
if in writing and mailed, first-class postage prepaid, to each Holder affected
by such event, at his address as it appears in the Security Register, not later
than the latest date, and not earlier than the earliest date, prescribed for the
giving of such notice. In any case where notice to Holders is given by mail,
neither the
<PAGE>   17
                                                                              10


failure to mail such notice, nor any defect in any notice so mailed, to any
particular Holder shall affect the sufficiency of such notice with respect to
other Holders. Where this Indenture provides for notice in any manner, such
notice may be waived in writing by the Person entitled to receive such notice,
either before or after the event, and such waiver shall be the equivalent of
such notice. Waivers of notice by Holders shall be filed with the Trustee, but
such filing shall not be a condition precedent to the validity of any action
taken in reliance upon such waiver.

      In case by reason of the suspension of regular mail service or by reason
of any other cause it shall be impracticable to give such notice by mail, then
such notification as shall be made with the approval of the Trustee shall
constitute a sufficient notification for every purpose hereunder.

      Section 1.07.     Conflict with Trust Indenture Act.

      If any provision hereof limits, qualifies or conflicts with the duties
imposed by any of Section 310 through 317, inclusive, of the Trust Indenture Act
through the operation of Section 318(c) thereof, such imposed duties shall
control.

      Section 1.08.     Effect of Headings and Table of Contents.

      The Article and Section headings herein and the Table of Contents are for
convenience only and shall not affect the construction hereof.

      Section 1.09.     Successors and Assigns.

      All covenants and agreements in this Indenture by the Company shall bind
its successors and assigns, whether so expressed or not.

      Section 1.10.     Separability Clause.

      In case any provision in this Indenture or in the Securities 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.

      Section 1.11.     Benefits of Indenture.

      Nothing in this Indenture or in the Securities, express or implied, shall
give to any Person (other than the parties hereto, any Security Registrar, any
Paying Agent, any Authenticating Agent, and their successors hereunder, and the
Holders of Securities) any benefit or any legal or equitable right, remedy or
claim under this Indenture.

      Section 1.12.     Governing Law.

      This Indenture and the Securities shall be deemed to be contracts made
under the law of the State of New York and for all purposes shall be construed
in accordance with the law of said State.
<PAGE>   18
                                                                              11


      Section 1.13.     Legal Holidays.

      In any case where any Interest Payment Date, Redemption Date or Stated
Maturity of any Security shall not be a Business Day, then (notwithstanding any
other provision of this Indenture or the Security) payment of interest or
principal need not be made on such date, but may be made on the next succeeding
Business Day with the same force and effect as if made on the Interest Payment
Date or Redemption Date, or at the Stated Maturity, and no interest shall accrue
for the period from and after such Interest Payment Date, Redemption Date or
Stated Maturity, as the case may be.

      Section 1.14.     Indenture and Securities Solely Corporate Obligations.

      No recourse for the payment of principal of or interest on any Security or
for any claim based on any Security or this Indenture shall be had against any
director or officer or stockholder, past, present or future, of the Company. Any
such claim against any such Person is expressly waived as a condition of, and as
consideration for, the execution and delivery of this Indenture and the issue of
the Securities.

      Section 1.15.     No Security Interest Created.

      Nothing in this Indenture or in the Securities, expressed or implied,
shall be construed to constitute a security interest under the Uniform
Commercial Code or similar legislation, as now or hereafter enacted and in
effect, in any jurisdiction where property of the Company or its subsidiaries is
located.

                                   ARTICLE Two

                                 SECURITY FORMS

      Section 2.01. Forms Generally. The Securities of each series shall be in
substantially such form as shall be established by or pursuant to a resolution
of the Board of Directors or in one or more indentures supplemental hereto, in
each case with such appropriate insertions, omissions, substitutions and other
variations as are required or permitted by this Indenture, and may have such
letters, numbers or other marks of identification and such legends or
endorsements placed thereon as may be required to comply with any law or with
any rules made pursuant thereto or with any rules of any securities exchange or
as may, consistently herewith, be determined by the officers executing such
Securities, as evidenced by their execution of the Securities.

      The definitive Securities shall be printed, lithographed or engraved on
steel engraved borders or may be produced in any other manner, all as determined
by the officers executing such Securities, as evidenced by their execution of
such Securities.

      Section 2.02. Form of Trustee's Certificate of Authentication. The
Trustee's certificate of authentication on all Securities shall be in
substantially the following form:

      This is one of the Securities of the series designated therein referred to
in the within-mentioned Indenture.
<PAGE>   19
                                                                              12


                                    Citibank, N.A.,
                                    as Trustee



                                    By
                                       ----------------------------------
                                                Authorized Signatory

                                    Dated:
                                          -------------------------------



      Section 2.03. Securities in Global Form. If any Security of a series is
issuable in global form, such Global Security may provide that it shall
represent the aggregate amount of Outstanding Securities from time to time
endorsed thereon and may also provide that the aggregate amount of Outstanding
Securities represented thereby may from time to time be reduced to reflect
exchanges. Any endorsement of a Global Security to reflect the amount, or any
increase or decrease in the amount, of Outstanding Securities represented
thereby shall be made by the Trustee and in such manner as shall be specified in
such Global Security. Any instructions by the Company with respect to a Global
Security, after its initial issuance, shall be in writing but need not comply
with Section 1.02.

      None of the Company, the Trustee, any Paying Agent or the Security
Registrar will have any responsibility or liability for any aspect of the
records relating to or payments made on account of beneficial ownership
interests of a Global Security or for maintaining, supervising or reviewing any
records relating to such beneficial ownership interests.

                                  ARTICLE Three

                                 THE SECURITIES

      Section 3.01. Amount Unlimited; Issuable in Series. The aggregate
principal amount of Securities which may be authenticated and delivered under
this Indenture is unlimited.

      The Securities may be issued in one or more series. There shall be
established in or pursuant to a Board Resolution or established in one or more
indentures supplemental hereto, prior to the issuance of Securities of any
series,

            (1) the title of the Securities of the series, including CUSIP
      Numbers (which shall distinguish the Securities of the series from all
      other Securities);

            (2) any limit upon the aggregate principal amount of the Securities
      of the series which may be authenticated and delivered under this
      Indenture (except for Securities authenticated and delivered upon
      registration of transfer of, or in exchange for, or in lieu of, other
      Securities of the series pursuant to Section 3.05, 3.06, 3.07, 9.06 or
      11.03);
<PAGE>   20
                                                                              13


            (3) the date or dates on which the principal and premium, if any, of
      the Securities of the series is payable;

            (4) the rate or rates at which the Securities of the series shall
      bear interest, or the method by which such rate or rates shall be
      determined, if any, the date or dates from which such interest shall
      accrue, or the method by which such date or dates shall be determined, the
      interest payment dates on which such interest shall be payable and the
      record dates for the determination of Holders to whom interest is payable;

            (5) the place or places, if any, in addition to or instead of the
      Corporate Trust Office of the Trustee, where the principal of (and
      premium, if any) and interest on Securities of the series shall be
      payable; the extent to which, or the manner in which, any interest payable
      on any Global Security on an Interest Payment Date will be paid, if other
      than in the manner provided in Section 3.07; and the manner in which any
      principal of, or premium, if any, on, any Global Security will be paid, if
      other than as set forth elsewhere herein;

            (6) the price or prices at which, the period or periods within which
      and the terms and conditions upon which Securities of the series may be
      redeemed, in whole or in part, at the option of the Company, pursuant to
      any sinking fund or otherwise;

            (7) the obligation, if any, of the Company to redeem, purchase or
      repay Securities of the series pursuant to any sinking fund or analogous
      provisions or at the option of a Holder thereof and the price or prices at
      which and the period or periods within which and the terms and conditions
      upon which Securities of the series shall be redeemed, purchased or
      repaid, in whole or in part, pursuant to such obligation;

            (8) if other than denominations of $1,000 and any integral multiple
      thereof, the denominations in which Securities of the series shall be
      issuable;

            (9) if other than the principal amount thereof, the portion of the
      principal amount of Securities of the series which shall be payable upon
      declaration of acceleration of the maturity thereof pursuant to Section
      5.02 or provable in bankruptcy pursuant to Section 5.03;

            (10)  any Events of Default with respect to the Securities of a
      particular series, if not set forth herein;

            (11) the extent to which the defeasance provisions of this Indenture
      do not apply to the Securities of the series;

            (12) whether the Securities of the series shall be issued in whole
      or in part in the form of one or more Global Securities and, in such case,
      the U.S. Depositary for such Global Security or Securities; the manner in
      which and the circumstances under which Global Securities representing
      Securities of the series may be exchanged for Securities in
<PAGE>   21
                                                                              14


      definitive form, if other than, or in addition to, the manner and
      circumstances specified in Section 3.07;

            (13) the ranking of the Securities of such series, if other than on
      a parity with all other unsecured, unsubordinated indebtedness of the
      Company;

            (14) provisions, if any, with regard to the conversion or exchange
      of the Securities of such series, at the option of the Holders thereof or
      the Company, as the case may be, for or into new Securities of a different
      series or common stock or other securities of the Company;

            (15) which, if any, of the Eligible Guarantors shall guarantee the
      Securities on the terms set forth in Article Fifteen (each, a
      "Guarantor"); and

            (16) any other terms of the series (which terms shall not be
      inconsistent with the provisions of this Indenture).

      All Securities of any one series shall be substantially identical except
as to denomination and except as may otherwise be provided in or pursuant to
such resolution of the Board of Directors or in any such indenture supplemental
hereto.

      Section 3.02. Denominations. The Securities of each series shall be
issuable in registered form without coupons in such denominations as shall be
specified as contemplated by Section 3.01. In the absence of any such
specification with respect to the Securities of any series, the Securities of
such series shall be issuable in denominations of $1,000 and any integral
multiple thereof.

      Section 3.03. Authentication and Dating. At any time and from time to time
after the execution and delivery of this Indenture, the Company may deliver
Securities of any series executed by the Company to the Trustee for
authentication. Except as otherwise provided in this Article Three, the Trustee
shall thereupon authenticate and deliver said Securities to or upon the written
order of the Company, signed by the Chairman of the Board individually or by any
Vice President acting together with the Chief Financial Officer, Treasurer,
Chief Accounting Officer or any Assistant Treasurer. In authenticating such
Securities, and accepting the additional responsibilities under this Indenture
in relation to such Securities, the Trustee shall receive, and (subject to
Section 6.01) shall be fully protected in relying upon:

            (1) a copy of any Board Resolution relating thereto and, if
      applicable, an appropriate record of any action taken pursuant to such
      resolution, in each case certified by the Secretary or an Assistant
      secretary of the Company;

            (2)   an executed supplemental indenture, if any;

            (3)   an Officers' Certificate; and

            (4)   an Opinion of Counsel which shall also state
<PAGE>   22
                                                                              15


                  (a) that the form of such Securities has been established by
            or pursuant to a Board Resolution or by a supplemental indenture as
            permitted by Section 2.01 in conformity with the provisions of this
            Indenture;

                  (b) that the terms of such Securities have been established by
            or pursuant to a Board Resolution or by a supplemental indenture as
            permitted by Section 3.01 in conformity with the provisions of this
            Indenture;

                  (c) that such Securities, when authenticated and delivered by
            the Trustee and issued by the Company in the manner and subject to
            any conditions specified in such Opinion of Counsel, will constitute
            valid and legally binding obligations of the Company, enforceable in
            accordance with their terms, subject to bankruptcy, insolvency,
            reorganization and other laws of general applicability relating to
            or affecting the enforcement of creditors' rights and to general
            equity principles; and

                  (d) that all laws and requirements in respect of the execution
            and delivery by the Company of the Securities have been complied
            with and that authentication and delivery of the Securities by the
            Trustee will not violate the terms of the Indenture.

      The Trustee shall have the right to decline to authenticate and deliver
any Securities under this Section if the Trustee, being advised by counsel,
determines that such action may not lawfully be taken or if the Trustee in good
faith shall determine that such action would expose the Trustee to personal
liability to existing Holders.

      Each Security shall be dated the date of its authentication.

      Section 3.04. Execution of Securities. The Securities shall be signed in
the name and on behalf of the Company by the manual or facsimile signatures of
the Chairman of the Board or its Vice Chairman or its President or one of its
Vice Presidents under its corporate seal (which may be printed, engraved or
otherwise reproduced thereon, by facsimile or otherwise), and attested by its
Treasurer or Secretary or one of its Assistant Treasurers or Assistant
Secretaries. Only such Securities as shall bear thereon a certificate of
authentication substantially in the form hereinbefore recited, executed by the
Trustee, shall be entitled to the benefits of this Indenture or be valid or
obligatory for any purpose. Such certificate by the Trustee upon any Security
executed by the Company shall be conclusive evidence that the Security so
authenticated has been duly authenticated and delivered hereunder and that the
Holder is entitled to the benefits of this Indenture.

      In case any officer of the Company who shall have signed any of the
Securities shall cease to be such officer before the Securities so signed shall
have been authenticated and delivered by the Trustee, or disposed of by the
Company, such Securities nevertheless may be authenticated and delivered or
disposed of as though the person who signed such Securities had not ceased to be
such officer of the Company; and any Security may be signed on behalf of the
company by such persons as, at the actual date of the execution of such
Security, shall be the
<PAGE>   23
                                                                              16


proper officers of the Company, although at the date of the execution of this
Indenture any such person was not such an officer.

      Section 3.05. Exchange and Registration of Transfer of Securities.
Securities of any series may be exchanged for a like aggregate principal amount
of Securities of the same series of other authorized denominations. Securities
to be exchanged shall be surrendered at the office or agency to be maintained by
the Company in the Borough of Manhattan, The City of New York, as provided in
Section 10.02. The Trustee is hereby appointed "Security Registrar" for the
purpose of the registration of Securities and of transfer of Securities in the
Security Register as herein provided. The Company shall cause to be kept at the
Corporate Trust Office of the Trustee a register for each series of Securities
issued hereunder (hereinafter collectively referred to as the "Security
Register") in which, subject to such reasonable regulations at it may prescribe,
the Company shall provide for the registration of Securities and the transfer of
Securities as in this Article Three provided. The Security Register shall be in
written form or in any other form capable of being converted into written form
within a reasonable time. Upon due presentment for registration of transfer of
any Security of any series at such office or agency, the Company shall execute
and the Trustee shall register, authenticate and deliver in the name of the
transferee or transferees a new Security or Securities of the same series for an
equal aggregate principal amount.

      All Securities presented for registration of transfer or for exchange,
redemption or payment shall (if so required by the Company or the Security
Registrar) be duly endorsed by, or be accompanied by a written instrument or
instruments of transfer in form satisfactory to the Company and the Security
Registrar duly executed by, the registered Holder or his attorney duly
authorized in writing.

      No service charge shall be made for any exchange or registration of
transfer of Securities, but the Company may require payment of a sum sufficient
to cover any tax or other governmental charge that may be imposed in connection
therewith.

      The Company shall not be required to exchange or register the transfer of
(a) any Securities of any series for a period of 15 days next preceding any
selection of Securities of that series to be redeemed, or (b) any Securities
selected, called or being called for redemption except, in the case of any
Security to be redeemed in part, the portion thereof not so to be redeemed.

      Section 3.06. Mutilated, Destroyed, Lost or Stolen Securities. In case any
temporary or definitive Security shall become mutilated or be destroyed, lost or
stolen, the Company in the case of a mutilated Security shall, and in the case
of a lost, stolen or destroyed Security may in its discretion, execute, and upon
its request the Trustee shall authenticate and deliver, a new Security of the
same series bearing a number, letter or other distinguished symbol not
contemporaneously outstanding, in exchange and substitution for the mutilated
Security, or in lieu of and in substitution for the Security so destroyed, lost
or stolen, or if any such Security shall have matured or shall be about to
mature, instead of issuing a substituted Security, the Company may pay or
authorize the payment of the same without surrender thereof (except in the case
of a mutilated Security). In every case the applicant for a substituted Security
shall furnish to the Company and to the Trustee such security or indemnity as
may be required by them to
<PAGE>   24
                                                                              17


save each of them harmless, and, in every case of destruction, loss or theft,
the applicant shall also furnish to the Company and to the Trustee evidence to
their satisfaction of the destruction, loss or theft of such Security and of the
ownership thereof.

      The Trustee may authenticate any such substituted Security and deliver the
same upon the written request or authorization of any officer of the Company.
Upon the issuance of any substituted Security, the Company may require the
payment of a sum sufficient to cover any tax or other governmental charge that
may be imposed in relation thereto and any other expenses connected therewith
and in addition a further sum not exceeding two dollars for each Security so
issued in substitution.

      Every substituted Security issued pursuant to the provisions of this
Section 3.06 by virtue of the fact that any Security is destroyed, lost or
stolen shall constitute an additional contractual obligation of the Company,
whether or not the destroyed, lost or stolen Security shall be found at any
time, and shall be entitled to all the benefits of this Indenture equally and
proportionately with any and all other Securities of that series duly issued
hereunder. All Securities shall be held and owned upon the express condition
that the foregoing provisions are exclusive with respect to the replacement or
payment of mutilated, destroyed, lost or stolen Securities and shall preclude
(to the extent lawful) any and all other rights or remedies with respect to the
replacement or payment of negotiable instruments or other securities without
their surrender.

      Section 3.07. Temporary Securities. Pending the preparation of definitive
Securities of any series the Company may execute and the Trustee shall
authenticate and deliver temporary Securities (printed or lithographed).
Temporary Securities shall be issuable in any authorized denomination and
substantially in the form of the definitive Securities but with such omissions,
insertions and variations as may be appropriate for temporary Securities, all as
may be determined by the Company. Every such temporary Security shall be
executed by the Company and shall be authenticated by the Trustee upon the same
conditions and in substantially the same manner, and with the same effect, as
the definitive Securities. Without unreasonable delay the Company will execute
and deliver to the Trustee definitive Securities of such series and thereupon
any or all temporary Securities of such series may be surrendered in exchange
therefore, at the Corporate Trust Office of the Trustee, and the Trustee shall
authenticate and deliver in exchange for such temporary Securities an equal
aggregate principal amount of definitive Securities. Such exchange shall be made
by the Company at its own expense and without any charge therefor except that in
case of any such exchange involving any registration of transfer the Company may
require payment of a sum sufficient to cover any tax or other governmental
charge that may be imposed in relation thereto. Until so exchanged, the
temporary Securities shall in all respects be entitled to the same benefits
under this Indenture as definitive Securities authenticated and delivered
hereunder.

      If the Company shall establish pursuant to Section 3.01 that the
Securities of a series are to be issued in whole or in part in the form of one
or more Global Securities, then the Company shall execute and the Trustee shall,
in accordance with Section 3.03 and the Company Order with respect to such
series, authenticate and deliver one or more Global Securities in temporary or
permanent form that (i) shall represent and shall be denominated in an amount
equal to the aggregate principal amount of the Outstanding Securities of such
series to be represented by one or more Global Securities, (ii) shall be
registered in the name of the U.S. Depositary for such
<PAGE>   25
                                                                              18


Global Security or Securities or the nominee of such depositary, and (iii) shall
bear a legend substantially to the following effect: "This Security may not be
transferred except as a whole by the Depositary to a nominee of the Depositary
or by a nominee of the Depositary to the Depositary or another nominee of the
Depositary or by the Depositary or any such nominee to a successor Depositary or
a nominee of such successor Depositary, unless and until this Security is
exchanged in whole or in part for Securities in definitive form" and such other
legend as may be required by the U.S. Depositary.

      Notwithstanding any other provision of this Section or Section 3.07,
unless and until it is exchanged in whole or in part for Securities in
definitive form, a Global Security representing all or a portion of the
Securities of a series may not be transferred except as a whole by the U.S.
Depositary for such series to a nominee of such depositary or by a nominee of
such depositary to such depositary or another nominee of such depositary or by
such depositary or any such nominee to a successor U.S. Depositary for such
series or a nominee of such successor depositary.

      If at any time the U.S. Depositary for the Securities of a series notifies
the Company that it is unwilling or unable to continue as U.S. Depositary for
the Securities of such series or if at any time the U.S. Depositary for
Securities of a series shall no longer be a clearing agency registered and in
good standing under the Securities Exchange Act of 1934, as amended, or other
applicable statute or regulation, the Company shall appoint a successor U.S.
Depositary with respect to the Securities of such series. If a successor U.S.
Depositary for the Securities of such series is not appointed by the Company
within 90 days after the Company receives such notice or becomes aware of such
condition, the Company will execute, and the Trustee, upon receipt of a Company
Order for the authentication and delivery of definitive Securities of such
series, will authenticate and deliver, Securities of such series in definitive
form in an aggregate principal amount equal to the principal amount of the
Global Security or Securities representing such series in exchange for such
Global Security or Securities.

      The Company may at any time and in its sole discretion determine that the
Securities of any series issued in the form of one or more Global Securities
shall no longer be represented by such Global Security or Securities. In such
event, the Company will execute, and the Trustee, upon receipt of a Company
Order for the authentication and delivery of definitive Securities of such
series, will authenticate and deliver, Securities of such series in definitive
form and in an aggregate principal amount equal to the principal amount of the
Global Security or Securities representing such series in exchange for such
Global Security or Securities.

      If the Securities of any series shall have been issued in the form of one
or more Global Securities and if an Event of Default with respect to the
Securities of such series shall have occurred and be continuing, the Company
will promptly execute, and the Trustee, upon receipt of a Company Order for the
authentication and delivery of definitive Securities of such series, will
authenticate and deliver Securities of such series in definitive form and in an
aggregate principal amount equal to the principal amount of the Global Security
or Securities representing such series in exchange for such Global Security or
Securities.

      If specified by the Company pursuant to Section 3.01 with respect to
Securities of a series, the U.S. Depositary for such series of Securities may
surrender a Global Security for such
<PAGE>   26
                                                                              19


series of Securities in exchange in whole or in part for Securities of such
series in definitive form on such terms as are acceptable to the Company and
such depositary. Thereupon, the Company shall execute and the Trustee shall
authenticate and deliver, without charge:

            (1) to each Person specified by the U.S. Depositary a new Registered
      Security or Securities of the same series, of any authorized denomination
      as requested by such Person in an aggregate principal amount equal to and
      in exchange for such Person's beneficial interest in the Global Security;
      and

            (2) to the U.S. Depositary a new Global Security in a denomination
      equal to the difference, if any, between the principal amount of the
      surrendered Global Security and the aggregate principal amount of
      Securities delivered to Holders thereof.

      Upon the exchange of a Global Security in whole for Securities in
definitive form, such Global Security shall be cancelled by the Trustee.
Securities so issued in exchange for a Global Security shall be registered in
such names and in such authorized denominations as the U.S. Depositary for such
Global Security, pursuant to instructions from its direct or indirect
participants or otherwise, shall instruct the Trustee. The Trustee shall deliver
such Securities to the Persons in whose names such Securities are so registered.

      Section 3.08. Payment of Interest; Interest Rights Preserved. Interest on
any Security 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 that
Security (or one or more Predecessor Securities) is registered at the close of
business on the Regular Record Date for such interest.

      Any interest on any Security which is payable, but is not punctually paid
or duly provided for, on any Interest Payment Date or within 30 days thereafter
(herein called "Defaulted Interest") shall forthwith cease to be payable to the
registered Holder on the relevant Regular Record Date by virtue of having been
such Holder; and such Defaulted Interest may be paid by the Company, at its
election in each case, as provided in clause (1) or (2) below:

            (1) The Company may elect to make payment of any Defaulted Interest
      to the Persons in whose names the Securities (or their respective
      Predecessor Securities) are registered at the close of business on a
      Special Record Date for the payment of such Defaulted Interest, which
      shall be fixed in the following manner. The Company shall notify the
      Trustee in writing of the amount of Defaulted Interest proposed to be paid
      on each Security and the date of the proposed payment, and at the same
      time the Company 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 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 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 date of the proposed payment 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 Company of such Special Record Date and, in the
      name and at the expense of the Company, shall cause notice of the proposed
      payment of
<PAGE>   27
                                                                              20


      such Defaulted Interest and the Special Record Date therefor to be mailed,
      first-class postage prepaid, to each Holder at his address as it appears
      in the Security Register not less than 10 days prior to such Special
      Record Date. The Trustee may, in its discretion, in the name and at the
      expense of the Company, cause a similar notice to be published at least
      once in a newspaper, customarily published in the English language on each
      Business Day and of general circulation in the Borough of Manhattan, The
      City of New York, but such publication shall not be a condition precedent
      to the establishment of such Special Record Date. Notice of the proposed
      payment of such Defaulted Interest and the Special Record Date therefor
      having been mailed as aforesaid, such Defaulted Interest shall be paid to
      the Persons in whose names the Securities (or their respective Predecessor
      Securities) are registered on such Special Record Date and shall no longer
      be payable pursuant to the following clause (2).

            (2) The Company may make payment of any Defaulted Interest in any
      other lawful manner not inconsistent with the requirements of any
      securities exchange on which the Securities may be listed, and upon such
      notice as may be required by such exchange, if after notice given by the
      Company 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 Security
delivered under this Indenture upon registration of transfer of or in exchange
for or in lieu of any other Security shall carry the rights to interest accrued
and unpaid, and to accrue, which were carried by such other Security.

      Section 3.09. Persons Deemed Owners. Prior to due presentment of a
Security for registration of transfer, the Company, the Trustee, the
Authenticating Agent and any agent of the Company or the Trustee may treat the
Person in whose name the Security is registered as the owner of such Security
for the purpose of receiving payment of principal of, and (subject to Section
3.08) interest on, such Security and for all other purposes whatsoever, whether
or not such Security be overdue, and neither the Company, the Trustee, the
Authenticating Agent nor any agent of the Company or the Trustee shall be
affected by notice to the contrary.

      Section 3.10. Cancellation. All Securities surrendered for payment,
redemption, registration of transfer or exchange shall, if surrendered to any
Person other than the Trustee, be delivered to the Trustee, and any such
Securities and Securities surrendered directly to the Trustee for any such
purpose shall be promptly cancelled by it. The Company may at any time deliver
to the Trustee for cancellation any Securities previously authenticated and
delivered hereunder which the Company may have acquired in any manner
whatsoever, and all Securities so delivered shall be promptly cancelled by the
Trustee. No Securities shall be authenticated in lieu of or in exchange for any
Securities cancelled as provided in this Section, except as expressly permitted
by this Indenture. All cancelled Securities held by the Trustee shall be
disposed of by the Trustee in its customary manner.

      Section 3.11. Computation of Interest. Except as otherwise specified as
contemplated by Section 3.01 for Securities of any Series, interest on the
Securities of each series shall be computed on the basis of a 360-day year of
twelve 30-day months.
<PAGE>   28
                                                                              21


      Section 3.12. CUSIP Numbers. The Company in issuing the Securities may use
"CUSIP" numbers (if then generally in use), and, if so, the Trustee shall use
"CUSIP" numbers in notices of redemption as a convenience to Holders; provided
that any such notice may state that no representation is made as to the
correctness of such numbers either as printed on the Securities or as contained
in any notice of a redemption and that reliance may be placed only on the other
identification numbers printed on the Securities, and any such redemption shall
not be affected by any defect in or omission of such numbers. The Company will
promptly notify the Trustee of any change in the "CUSIP" numbers.

                                     ARTICLE Four

                              SATISFACTION AND DISCHARGE

      Section 4.01. Satisfaction and Discharge of Indenture. This Indenture
shall cease to be of further effect (except as to any surviving rights of
registration of transfer or exchange of Securities herein expressly provided
for), and the Trustee, on demand of and at the expense of the Company, shall
execute proper instruments acknowledging satisfaction and discharge of this
Indenture, when

            (1)   either

                  (A) all Securities theretofore authenticated and delivered
            (other than (i) Securities which have been destroyed, lost or stolen
            and which have been replaced or paid as provided in Section 3.06 and
            (ii) Securities for whose payment money has theretofore been
            deposited in trust or segregated and held in trust by the Company
            and thereafter repaid to the Company or discharged from such trust,
            as provided in Section 10.03) have been delivered to the Trustee for
            cancellation; or

                  (B) all such Securities not theretofore delivered to the
            Trustee for cancellation

                        (i)   have become due and payable, or

                        (ii) will become due and payable at their Stated
                  Maturities within one year, or

                        (iii) 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 Company,

            and the Company in the case of (i), (ii) or (iii) above, has
            deposited or caused to be deposited with the Trustee as trust funds
            in trust for the purpose an amount sufficient to pay and discharge
            the entire indebtedness on such Securities not theretofore delivered
            to the Trustee for cancellation, for principal (and premium, if any)
            and interest to the date of such deposit (in the case of Securities
            which
<PAGE>   29
                                                                              22


            have become due and payable) or to the Stated Maturity or Redemption
            Date, as the case may be;

            (2) the Company has paid or caused to be paid all other sums payable
      hereunder by the Company; and

            (3) the Company has delivered to the Trustee an Officers'
      Certificate and an Opinion of Counsel each stating that all conditions
      precedent herein provided for relating to the satisfaction and discharge
      of this Indenture have been complied with.

Notwithstanding the satisfaction and discharge of this Indenture, the
obligations of the Company to the Trustee under Section 6.07 and the obligations
of the Trustee to any Authenticating Agent under Section 6.14 shall survive such
satisfaction and discharge.

      Section 4.02. Application of Trust Money. All money deposited with the
Trustee pursuant to Section 4.01 shall be held in trust and applied by it, in
accordance with the provisions of the Securities and this Indenture, to the
payment, either directly or through any Paying Agent (including the Company
acting as its own Paying Agent) as the Trustee may determine, to the Persons
entitled thereto, of the principal (and premium, if any) and interest for whose
payment such money has been deposited with the Trustee; but such money need not
be segregated from other funds except to the extent required by law.

                                  ARTICLE Five

                                    REMEDIES

      Section 5.01.     Events of Default.

      "Events of Default", wherever used herein with respect to Securities of
any series, means any one of the following events and such other events as may
be established with respect to the Securities of that series as contemplated by
Section 3.01 hereof (whatever the reasons for such Event of Default and whether
it shall be voluntary or involuntary or be effected by operation of law pursuant
to any judgment, decree or order of any court or any order, rule or regulation
of any administrative or governmental body):

            (a) default in the payment of any installment of interest upon any
      Security of that series as and when the same shall become due and payable,
      and continuance of such default for a period of 30 days; or

            (b) default in the payment of any of the principal of and premium,
      if any, on any Security of that series as and when the same shall become
      due and payable, either at Maturity, upon redemption, by declaration,
      repayment or otherwise; or

            (c) default in the payment of any sinking fund installment as and
      when the same shall become due and payable by the terms of a Security of
      that series; or

            (d) failure on the part of the Company or a Guarantor duly to
      observe or perform any other of the covenants or agreements on the part of
      the Company or a
<PAGE>   30
                                                                              23

      Guarantor in this Indenture (other than those set forth exclusively in the
      terms of any particular series of Securities established as contemplated
      in this Indenture) continued for a period of 60 days after the date on
      which written notice of such failure, requiring the Company or a Guarantor
      to remedy the same, shall have been given to the Company or a Guarantor by
      the Trustee, or to the Company or a Guarantor and the Trustee by the
      Holders of at least 25 percent in aggregate principal amount of the
      Securities at the time Outstanding and stating that such notice is a
      "Notice of Default" hereunder; or

            (e) a court having jurisdiction in the premises shall enter a decree
      or order for relief in respect of the Company or a Guarantor in an
      involuntary case under any applicable bankruptcy, insolvency or other
      similar law now or hereafter in effect, or appointing a receiver,
      liquidator, assignee, custodian, trustee, sequestrator (or similar
      official) of the Company or its property or of a Guarantor or its
      property, as the case may be, or ordering the winding-up or liquidation of
      its affairs and such decree or order shall remain unstayed and in effect
      for a period of 60 consecutive days;

            (f) the Company or a Guarantor shall commence a voluntary case under
      any applicable bankruptcy, insolvency or other similar law now or
      hereafter in effect, or shall consent to the entry of an order for relief
      in an involuntary case under any such law, or shall consent to the
      appointment of or taking possession by a receiver, liquidator, assignee,
      trustee, custodian, sequestrator (or similar official) of the Company or
      its property or of a Guarantor or its property, as the case may be, or
      shall make any general assignment for the benefit of creditors, or shall
      fail generally to pay its debts as they become due; or

            (g) a Guarantee of a Security of that Series ceases to be in full
      force and effect (other than in accordance with the terms of the
      Guarantee) or a Guarantor of a Security of that Series denies or
      disaffirms its obligations under the Guarantee.

      Section 5.02.     Acceleration of Maturity; Rescission and Annulment.

      If an Event of Default described in clauses (a), (b), (c) or (g) or
established pursuant to Section 3.01 with respect to Securities of any series at
the time Outstanding occurs and is continuing, then and in each and every such
case, unless the principal of all the Securities of such series shall have
already become due and payable, either the Trustee or the Holders of not less
than 25 percent in aggregate principal amount of the Securities of such series
then Outstanding hereunder, by notice in writing to the Company (and to the
Trustee if given by Holders), may declare the principal amount (or, if the
Securities of that series are Original Issue Discount Securities, such portion
of the principal amount as may be specified in the terms of that series) of all
the Securities of such series to be due and payable immediately, and upon any
such declaration the same shall become and shall be immediately due and payable,
anything in this Indenture or in the Securities of such series contained to the
contrary notwithstanding. If an Event of Default described in clauses (d), (e)
or (f) in respect of the Company occurs and is continuing, then and in each and
every such case, unless the principal of all the Securities shall have already
become due and payable, either the Trustee or the Holders of not less than 25
percent in aggregate principal amount of all the Securities then Outstanding
hereunder, by notice in writing to the Company (and to the Trustee if given by
Holders), may declare the principal amount (or, if any Securities are Original
Issue Discount Securities, such portion of the principal amount as may be
specified in the terms thereof) of all the Securities then Outstanding hereunder
to be due and payable immediately, and upon any such declaration the same shall
become and shall be immediately due and payable, anything in this Indenture or
in the Securities contained to the contrary notwithstanding. If an Event of
Default described in clauses (d), (e) or (f) in respect of a Guarantor occurs
and is continuing, then and in each and every such case, unless the principal of
all the Securities guaranteed hereunder by such Guarantor shall have already
become due and payable, either the Trustee or the Holders of not less than 25
percent in aggregate principal amount of all the Securities guaranteed hereunder
by such Guarantor then Outstanding, by notice in writing to the Company (and to
the Trustee if given by Holders), may declare the principal amount (or, if any
such Securities are Original Issue Discount Securities, such portion of the
principal amount as may be specified in the terms thereof) of all such
Securities to be due and payable immediately, and upon any such declaration the
same shall become and shall be immediately due and payable, anything in this
Indenture or in the Securities contained to the contrary notwithstanding. The
foregoing provisions are, however, subject to the condition that if, at any time
after the principal amount (or, if the Securities of that series are Original
Issue Discount Securities, such portion of the principal amounts as may be
specified in the terms of that series) of the Securities of any series (or of
all the Securities, as the case may be) shall have been so declared due and
payable, and before any judgment or decree for the payment of the moneys due
shall have been obtained or entered as hereinafter provided, the Company shall
pay or shall deposit with the Trustee a sum sufficient to pay all matured
installments of interest upon all the Securities of such series (or of all the
Securities, as the case may be) and the principal of and premium, if any, on any
and all Securities of such series (or of all the Securities, as the case may be)
which shall have become due otherwise than by acceleration (with interest on
overdue installments of interest, to the extent that payment of such interest is
enforceable under applicable law, and on such principal and premium, if any, at
the rate of interest or Yield to Maturity (in the case of Original Issue
Discount Securities) borne by the Securities of such series
<PAGE>   31
                                                                           24

(or at the rates of interest or Yields to Maturity of all the Securities,as the
case may be), to the date of such payment or deposit) and the reasonable
expenses of the Trustee, and any and all defaults under this Indenture, other
than the nonpayment of principal of or premium, if any, or accrued interest on
Securities of such series (or of all the Securities, as the case may be) which
shall have become due by acceleration, shall have been cured or waived pursuant
to Section 5.08 - then and in every such case the Holders of a majority in
aggregate principal amount of the Securities of such series (or of all the
Securities, as the case may be) then Outstanding, by written notice to the
Company and to the Trustee, may waive all defaults with respect to that series
(or with respect to all Securities, as the case may be) and rescind and annul
such declaration and its consequences; but no such waiver or rescission and
annulment shall extend to or shall affect any subsequent default, or shall
impair any right consequent thereon.

      In case the Trustee or any Holder shall have proceeded to enforce any
right under this Indenture and such proceedings shall have been discontinued or
abandoned because of such rescission or annulment or for any other reason or
shall have been determined adversely to the Trustee or to such Holder, then and
in every such case the Company and the Trustee and the Holders shall be restored
respectively to their several positions and rights hereunder, and all rights,
remedies and powers of the Company and the Trustee and the Holders shall
continue as though no such proceeding had been taken.



      Section 5.03.     Payment of Securities on Default; Suit Therefor.

      The Company covenants that (a) in case default shall be made in the
payment of any installment of interest upon any of the Securities of any series
as and when the same shall become due and payable, and such default shall have
continued for a period of 30 days, or (b) in case default shall be made in the
payment of the principal of and premium, if any, on any of the Securities of any
series as and when the same shall become due and payable, whether at maturity of
the Securities of that series or upon redemption or by declaration, repayment or
otherwise -- then, upon demand of the Trustee, the Company will pay to the
Trustee, for the benefit of the Holders of the Securities of that series, the
whole amount that then shall have become due and payable on all such Securities
of that series for principal and premium, if any, or interest, or both, as the
case may be, with interest upon the overdue principal and (to the extent that
payment of such interest is enforceable under applicable law) upon the overdue
installments of interest at the
<PAGE>   32
                                                                              25


rate or Yield to Maturity (in the case of Original Issue Discount Securities)
borne by the Securities of that series; and, in addition thereto, such further
amount as shall be sufficient to cover the costs and expenses of collection,
including reasonable compensation to the Trustee, its agents, attorneys and
counsel, and any expenses or liabilities incurred by the Trustee hereunder other
than through its negligence or bad faith.

      In case the Company shall fail to pay such amounts forthwith upon such
demand, the Trustee, in its own name and as trustee of an express trust, shall
be entitled and empowered to institute any actions or proceedings at law or in
equity for the collection of the sums so due and unpaid, and may prosecute any
such action or proceeding to judgment or final decree, and may enforce any such
judgment or final decree against the Company or any other obligor upon such
Securities and collect in the manner provided by law out of the property of the
Company or any other obligor upon such Securities wherever situated the moneys
adjudged or decreed to be payable.

      In case there shall be pending proceedings for the bankruptcy or for the
reorganization of the Company or any other obligor on the Securities of any
series under any applicable bankruptcy, insolvency or similar law, or in case a
receiver or trustee shall have been appointed for the property of the Company or
such other obligor, or in the case of any other similar judicial proceedings
relative to the Company or other obligor upon the Securities of any series, or
to the creditors or property of the Company or such other obligor, the Trustee,
irrespective of whether the principal of the Securities of any series shall then
be due and payable as therein expressed or by declaration or otherwise and
irrespective of whether the Trustee shall have made any demand pursuant to the
provisions of this Section 5.03 shall be entitled and empowered, by intervention
in such proceedings or otherwise, to file and prove a claim or claims for the
whole amount of principal (and premium, if any) and interest (or, if the
Securities of that series are Original Issue Discount Securities, such portion
of the principal amount as may be specified in the terms of that series) owing
and unpaid in respect of the Securities of any series and, in case of any
judicial proceedings, to 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 and
of the Holders allowed in such judicial proceedings relative to the Company or
any other obligor on the Securities of any series, its or their creditors, or
its or their property, and to collect and receive any moneys or other property
payable or deliverable on any such claims, and to distribute the same after the
deduction of its charges and expenses; and any receiver, assignee or trustee in
bankruptcy or reorganization is hereby authorized by each of the Holders to make
such 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 compensation and expenses, including counsel fees incurred
by it up to the date of such distribution. To the extent that such payment of
reasonable compensation, expenses and counsel fees out of the estate in any such
proceedings shall be denied for any reason, payment of the same shall be secured
by a lien on, and shall be paid out of, any and all distributions, dividends,
moneys, securities and other property which the Holders of the Securities of any
series may be entitled to receive in such proceedings, whether in liquidation or
under any plan of reorganization or arrangement or otherwise.

      All rights of action and of asserting claims under this Indenture, or
under any of the Securities, may be enforced by the Trustee without the
possession of any of the Securities, or the production thereof on any trial or
other proceeding relative thereto, and any such suit or
<PAGE>   33
                                                                              26


proceeding instituted by the Trustee shall be brought in its own name as trustee
of an express trust, and any recovery of judgment shall be for the ratable
benefit of the Holders of all the Securities in respect of which such action was
taken.

      Section 5.04. Application of Moneys Collected by Trustee. Any moneys
collected by the Trustee under this Article Five shall be applied in the order
following, at the date or dates fixed by the Trustee for the distribution of
such moneys, upon presentation of the several Securities in respect of which
moneys have been collected, and stamping thereon the payment, if only partially
paid, and upon surrender thereof if fully paid:

            FIRST: To the payment of costs and expenses of collection and
      reasonable compensation to the Trustee, its agents, attorneys and counsel,
      and of all other expenses and liabilities incurred, and all advances made,
      by the Trustee except as a result of its negligence or bad faith;

            SECOND: In case the principal of the Outstanding Securities in
      respect of which such moneys have been collected shall not have become due
      and be unpaid, to the payment of interest on the Securities of that
      series, in the order of the maturity of the installments of such interest,
      with interest (to the extent that such interest has been collected by the
      Trustee) upon the overdue installments of interest at the rate or Yield to
      Maturity (in the case of Original Issue Discount Securities) borne by the
      Securities of that series, such payments to be made ratably to the persons
      entitled thereto;

            THIRD: In case the principal of the outstanding Securities in
      respect of which such moneys have been collected shall have become due, by
      declaration or otherwise, to the payment of the whole amount then owing
      and unpaid upon the Securities of that series for principal and premium,
      if any, and interest, with interest on the overdue principal and premium,
      if any, and (to the extent that such interest has been collected by the
      Trustee) upon overdue installments of interest at the rate or Yield to
      Maturity (in the case of Original Issue Discount Securities) borne by the
      Securities of that series; and in case such moneys shall be insufficient
      to pay in full the whole amounts so due and unpaid upon the Securities of
      that series, then to the payment of such principal and premium, if any,
      and interest without preference or priority of principal and premium, if
      any, over interest, or of interest over principal and premium, if any, or
      of any installment of interest over any other installment of interest, or
      of any Security of that series over any other Security of that series,
      ratably to the aggregate of such principal and premium, if any, and
      accrued and unpaid interest.

Any surplus then remaining shall be paid to the Company.

      Section 5.05. Proceedings by Holders. No Holder of any Security of any
series shall have any right by virtue of or by availing of any provision of this
Indenture to institute any suit, action or proceeding in equity or at law upon
or under or with respect to this Indenture or for the appointment of a receiver
or trustee, or for any other remedy hereunder, unless such Holder previously
shall have given to the Trustee written notice of default and of the continuance
thereof, as hereinbefore provided, and unless also the Holders of not less than
25 percent in aggregate principal amount of the Securities of that series then
Outstanding, or, in the case of any
<PAGE>   34
                                                                              27


Event of Default in respect of the Company described in clause (d), (e) or (f)
of Section 5.01, 25 percent in aggregate principal amount of all Securities then
Outstanding, or, in the case of any Event of Default in respect of a Guarantor
described in clause (d), (e) or (f) of Section 5.01, 25 percent in aggregate
principal amount of all Securities guaranteed hereunder by such Guarantor then
Outstanding, shall have made written request upon the Trustee to institute such
action, suit or proceeding in its own name as Trustee hereunder and shall have
offered to the Trustee such reasonable indemnity as it may require against the
costs, expenses and liabilities to be incurred therein or thereby, and the
Trustee for 60 days after its receipt of such notice, request and offer of
indemnity, shall have neglected or refused to institute any such action, suit or
proceeding, it being understood and intended, and being expressly covenanted by
the taker and Holder of every Security with every other taker and Holder and the
Trustee, that no one or more Holders shall have any right in any manner whatever
by virtue of or by availing of any provision of this Indenture to affect,
disturb or prejudice the rights of any other Holder, or to obtain or seek to
obtain priority over or preference to any other such Holder, or to enforce any
right under this Indenture, except in the manner herein provided and for the
equal, ratable and common benefit of all such Holders.

      Notwithstanding any other provisions in this Indenture, however, the right
of any Holder of any Security to receive payment of the principal of and
premium, if any, and interest on such Security, on or after the respective due
dates expressed in such Security, or to institute suit for the enforcement of
any such payment on or after such respective dates shall not be impaired or
affected without the written consent of such Holder.

      Section 5.06. Proceedings by Trustee. In case of an Event of Default
hereunder the Trustee may in its discretion proceed to protect and enforce the
rights vested in it by this Indenture by such appropriate judicial proceedings
as the Trustee shall deem necessary to protect and enforce any of such rights,
either by suit in equity or by action at law or by proceeding in bankruptcy or
otherwise, whether for the specific enforcement of any covenant or agreement
contained in this Indenture or in aid of the exercise of any power granted in
this Indenture, or to enforce any other legal or equitable right vested in the
Trustee by this Indenture or by law.

      Section 5.07. Remedies Cumulative and Continuing. All powers and remedies
given by this Article Five to the Trustee or to the Holders shall, to the extent
permitted by law, be deemed cumulative and not exclusive of any thereof or of
any other powers and remedies available to the Trustee or the Holders, by
judicial proceedings or otherwise, to enforce the performance or observance of
the covenants and agreements contained in this Indenture, and no delay or
omission of the Trustee or of any Holder to exercise any right or power accruing
upon any default occurring and continuing as aforesaid shall impair any such
right or power, or shall be construed to be a waiver of any such default or an
acquiescence therein; and, subject to the provisions of Section 5.05, every
power and remedy given by this Article Five or by law to the Trustee or to the
Holders may be exercised from time to time, and as often as shall be deemed
expedient, by the Trustee or by the Holders.

      Section 5.08. Direction of Proceedings and Waiver of Defaults by Majority
of Holders. The Holders of a majority in aggregate principal amount of the
Securities of all series at the time Outstanding shall have the right to direct
the time, method, and place of conducting any proceeding for any remedy
available to the Trustee, or exercising any trust or power conferred on the
Trustee with respect to the Securities of such series; provided, however, that
(subject to the provisions of Section 6.01) the Trustee shall have the right to
decline to follow any such direction if the Trustee, being advised by counsel,
determines that the action or proceeding so directed may not lawfully be taken
or if the Trustee in good faith shall determine that the action or

<PAGE>   35
                                                                              28


proceedings so directed would involve the Trustee in personal liability. Subject
to Section 5.02, the Holders of a majority in aggregate principal amount of the
Securities of that series at the time Outstanding may on behalf of the Holders
of all of the Securities of that series waive any past default or Event of
Default described in clauses (a), (b), (c) or (g) of Section 5.01, or any other
Event of Default for such series specified in the terms thereof as contemplated
by Section 3.01 (or, in the case of an event in respect of the Company specified
in clause (d), (e) or (f) of Section 5.01, the Holders of a majority in
aggregate principal amount of all the Securities then Outstanding may waive any
such default or Event of Default, or, in the case of an event in respect of a
Guarantor specified in clause (d), (c) or (f) of Section 5.01, the Holders of a
majority in aggregate principal amount of all the Securities guaranteed
hereunder by such Guarantor then outstanding may waive any such default of Event
of Default), and its consequences except a default in the payment of interest,
or premium, if any, on, or the principal of any of the Securities. Upon any such
waiver the Company, the Trustee and the Holders of the Securities of that series
(or of all of the Securities, as the case may be) shall be restored to their
former positions and rights hereunder, respectively; but no such waiver shall
extend to any subsequent or other default or Event of Default or impair any
right consequent thereon. Whenever any default or Event of Default hereunder
shall have been waived as permitted by this Section 5.08, said default or Event
of Default shall for all purposes of the Securities of that series and this
Indenture be deemed to have been cured and to be not continuing.

      Section 5.09. Undertaking to Pay Costs. All parties to this Indenture
agree, and each Holder of any Security by his acceptance thereof shall be deemed
to have agreed, that any court may in its discretion require, 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, the filing
by any party litigant in such suit of an undertaking to pay the costs of such
suit, and that such court may in its discretion assess reasonable costs,
including reasonable attorneys' fees and expenses, against any party litigant in
such suit, having due regard to the merits and good faith of the claims or
defenses made by such party litigant; but the provisions of this Section 5.09
shall not apply to any suit instituted by the Trustee, to any suit instituted by
any Holder of the Securities of any series or group of such Holders, holding in
the aggregate more than ten percent in principal amount of the Outstanding
Securities of that series (or, in the case of any suit relating to or arising
under clause (d), (e) or (f) of Section 5.01 in principal respect of the
Company, ten percent in principal amount of the aggregate Outstanding Securities
or, in the case of any suit relating to or arising under clause (d), (c) or (f)
of Section 5.01 in respect of a Guarantor, ten percent in principal amount of
the aggregate Outstanding Securities guaranteed hereunder by such Guarantor) or
to any suit instituted by any Holder for the enforcement of the payment of the
principal of or premium, if any, or interest on any Security against the Company
on or after the due date expressed in such Security.

                                   ARTICLE SIX

                                   THE TRUSTEE

      Section 6.01.     Certain Duties and Responsibilities.

      (a)   Except during the continuance of an Event of Default,

            (1) 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
<PAGE>   36
                                                                              29


            (2) 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 or opinions furnished
      to the Trustee and conforming to the requirements of this Indenture; but
      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 be under a duty to examine the same to determine whether or
      not they substantially conform to the requirements of this Indenture.

      (b) In case an Event of Default with respect to the Securities of a series
has occurred and is continuing, the Trustee shall exercise such of the rights
and powers vested in it by this Indenture with respect to such series, and use
the same degree of care and skill in their exercise, as a prudent man would
exercise or use under the circumstances in the conduct of his own affairs.

      (c) No provision of this Indenture shall be construed to relieve the
Trustee from liability for its own negligent action, its own negligent failure
to act, or its own willful misconduct, except that

            (1)   this Subsection shall not be construed to limit the effect of
      Subsection (a) of this Section;

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

            (3) the Trustee shall not be liable with respect to any action taken
      or omitted to be taken by it in good faith in accordance with the
      direction of the Holders pursuant to Section 5.08 relating to the time,
      method and place of conducting any proceeding for any remedy available to
      the Trustee, or exercising any trust or power conferred upon the Trustee,
      under this Indenture; and

            (4) no provision of this Indenture shall require the Trustee to
      expend or risk its own funds or otherwise incur any financial liability in
      the performance of any of its duties hereunder, or in the exercise of any
      of its rights or powers.

      (d) Whether or not therein expressly so provided, 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.

      Section 6.02.     Notice of Defaults.

      Within 90 days after the occurrence of any default with respect to the
Securities of any series, the Trustee shall transmit by mail to all Holders of
Securities of that Series, as their names and addresses appear in the Security
Register, notice of all defaults with respect to that Series actually known to a
Responsible Officer of the Trustee, unless such defaults shall have been cured
or waived before the giving of such notice; provided, however, that, except in
the case of a default in the payment of the principal of or premium, if any, or
interest on any of the Securities of such series or in the making of any sinking
fund payment with respect to such series, the
<PAGE>   37
                                                                           30

Trustee shall be protected in withholding such notice if and so long as the
board of directors, the executive committee or a trust committee of directors
and/or Responsible Officers of the Trustee in good faith determines that the
withholding of such notice is in the interests of the Holders; and provided,
further, that in the case of any default of the character specified in clause
(d) of Section 5.01 no such notice to Holders shall be given until at least 30
days after the occurrence thereof. For the purpose of this Section, the term
"default" means any event which is, or after notice or lapse of time or both
would become, an Event of Default.

      Section 6.03.     Certain Rights of Trustee.

      Except as otherwise provided in Section 6.01:

            (a) the Trustee may conclusively rely and shall be fully protected
      in acting or refraining from acting upon any resolution, certificate,
      statement, instrument, opinion, report, notice, request, direction,
      consent, order, bond, debenture or other paper or document (whether in its
      original or facsimile form) believed by it to be genuine and to have been
      signed or presented by the proper party or parties;

            (b) any request or direction of the Company mentioned herein shall
      be sufficiently evidenced by a Company Request or Company Order and any
      resolution of the Board of Directors may be sufficiently evidenced by a
      Board Resolution;

            (c) whenever in the administration of this Indenture the Trustee
      shall deem it desirable that a matter be proved or established prior to
      taking, suffering or omitting any action hereunder, the Trustee (unless
      other evidence be herein specifically prescribed) may, in the absence of
      bad faith on its part, rely upon an Officers' Certificate;

            (d) the Trustee may consult with the counsel of its own selection
      and the advice of such counsel or any Opinion of Counsel shall be full and
      complete authorization and protection in respect of any action taken,
      suffered or omitted by it hereunder in good faith and in reliance thereon;

            (e) 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 pursuant to this Indenture, unless such
      Holders shall have offered to the Trustee reasonable security or indemnity
      satisfactory to it against the costs, expenses and liabilities which might
      be incurred by it in complying with such request or direction;

            (f) the Trustee shall not be bound to make any investigation into
      the facts or matters stated in any resolution, certificate, statement,
      instrument, opinion, report, notice, request, direction, consent, order,
      bond, debenture or other paper or 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 shall determine to make
      such further inquiry or investigation, it shall be entitled to examine the
      books, records and premises of the Company, personally or by agent or
      attorney at the expense of the Company and shall incur no liability of any
      kind by reason of such inquiry or investigation;


<PAGE>   38
                                                                           31

            (g) the Trustee may execute any of the trusts or powers hereunder or
      perform any duties hereunder either directly or by or through agents or
      attorneys and the Trustee shall not be responsible for any misconduct or
      negligence on the part of any agent or attorney appointed with due care by
      it hereunder;

            (h) the Trustee shall not be deemed to have notice of any Default or
      Event of Default unless a Responsible Officer of the Trustee has actual
      knowledge thereof or unless written notice of any event which is in fact
      such a default is received by the Trustee at the Corporate Trust Office of
      the Trustee, and such notice references the Securities and this Indenture;
      and

            (i) the rights, privileges, protections, immunities and benefits
      given to the Trustee, including, without limitation, its right to be
      indemnified, are extended to, and shall be enforceable by, the Trustee in
      each of its capacities hereunder, and each agent, custodian and other
      Person employed to act hereunder.

      Section 6.04.     Not Responsible for Recitals or Issuance of Securities.

      The recitals contained herein and in the Securities, except the Trustee's
certificate of authentication, shall be taken as the statements of the Company,
and the Trustee and any Authenticating Agent assume no responsibility for their
correctness. The Trustee and any Authenticating Agent make no representations as
to the validity or sufficiency of this Indenture or of the Securities. The
Trustee shall not be accountable for the use or application by the Company of
the Securities or the proceeds thereof.

      Section 6.05.     May Hold Securities.

      The Trustee, any Paying Agent, Security Registrar, Authenticating Agent or
any other agent of the Company or of the Trustee, in its individual or any other
capacity, may become the owner or pledgee of Securities and, subject to Sections
6.08 and 6.13, may otherwise deal with the Company with the same rights it would
have if it were not Trustee, Paying Agent, Security Registrar, Authenticating
Agent or such other agent.

      Section 6.06.     Money Held in Trust.

      Money held by the Trustee in trust hereunder need not be segregated from
other funds except to the extent required by law. The Trustee shall be under no
liability for interest on any money received by it hereunder except as otherwise
agreed with the Company.

      Section 6.07.     Compensation and Reimbursement.

      The Company agrees

            (1) to pay to the Trustee from time to time reasonable compensation
      for all services rendered by it hereunder (which compensation shall not be
      limited by any provision of law in regard to the compensation of a trustee
      of an express trust);
<PAGE>   39
                                                                              32


            (2) except as otherwise expressly provided herein, to reimburse the
      Trustee upon its request for all expenses, disbursements and advances
      incurred or made by the Trustee in accordance with any provision of this
      Indenture (including the reasonable compensation and the expenses and
      disbursements of its agents and counsel), except any such expense,
      disbursement or advance as shall be determined by a court of competent
      jurisdiction to have been caused by its own negligence or willful
      misconduct; and

            (3) to fully indemnify the Trustee, any predecessor Trustee and
      their agents for, and to hold them harmless against, any and all loss,
      liability, claim, damage or expense (including legal fees and expenses)
      incurred without negligence or willful misconduct on their part, arising
      out of or in connection with the acceptance or administration of this
      trust, including the costs and expenses of defending themselves against
      any claim or liability in connection with the exercise or performance of
      any of their powers or duties hereunder.

      As security for the performance of the obligations of the Company under
this Section the Trustee shall have a lien prior to the Securities upon all
property and funds held or collected by the Trustee as such, except funds held
in trust for the payment of principal of (or premium, if any) or interest on
Securities.

      Section 6.08.     Disqualification; Conflicting Interests.

      The Trustee for the Securities shall be subject to the provisions of
Section 310(b) of the Trust Indenture Act during the period of time required
thereby. Nothing herein shall prevent the Trustee from filing with the
Commission the application referred to in the penultimate paragraph of Section
310(b) of the Trust Indenture Act. In determining whether the Trustee has a
conflicting interest as defined in Section 310(b) of the Trust Indenture Act
with respect to the Securities of any series, there shall be excluded Securities
of any particular series of Securities other than that series.

      Section 6.09.     Corporate Trustee Required; Eligibility.

      There shall at all times be a Trustee hereunder which shall be

            (1) a corporation organized and doing business under the laws of the
      United States of America, any state thereof, or the District of Columbia,
      authorized under such laws to exercise corporate trust powers, and subject
      to supervision or examination by Federal or State authority, or

            (2) a corporation or other Person organized and doing business under
      the laws of a foreign government that is permitted to act as a Trustee
      pursuant to a rule, regulation, or other order of the Commission,
      authorized under such laws to exercise corporate trust powers, and subject
      to supervision or examination by authority of such foreign government or a
      political subdivision thereof substantially equivalent to supervision or
      examination applicable to United States institutional trustee,

      having a combined capital and surplus of at least $50,000,000 and having
its Corporate Trust Office in the Borough of Manhattan, the City of New York, or
such other city as
<PAGE>   40
                                                                              33


contemplated by Section 3.01 with respect to any series of Securities. If such
corporation publishes reports of condition at least annually, pursuant to law or
to requirements of the aforesaid supervising or examining authority, then for
the purposes of this Section, the combined capital and surplus of such
corporation shall be deemed to be its combined capital and surplus as set forth
in its most recent report of condition so published. Neither the Company nor any
Person directly or indirectly controlling, controlled by, or under the common
control with the Company shall serve as Trustee for the Securities. If at any
time the Trustee shall cease to be eligible in accordance with the provisions of
this Section, it shall resign immediately in the manner and with the effect
hereunder specified in this Article.

      Section 6.10.     Resignation and Removal; Appointment of Successor.

      (a) No resignation or removal of the Trustee and no appointment of a
successor Trustee pursuant to this Article shall become effective until the
acceptance of appointment by the successor Trustee under Section 6.11.

      (b) The Trustee may resign at any time with respect to one or more or all
series of Securities by giving written notice thereof to the Company. If an
instrument of acceptance by a successor Trustee required by Section 6.11 shall
not have been delivered to the Trustee within 30 days after the giving of such
notice of resignation, the resigning Trustee may petition at the expense of the
Company any court of competent jurisdiction for the appointment of a successor
Trustee with respect to the Securities of such series.

      (c) The Holders of a majority in aggregate principal amount of the
Securities of one or more series (each series voting as a class) or all series
at the time Outstanding may at any time remove the Trustee with respect to the
applicable series or all series, as the case may be, and by written notice of
such action to the Company, the Trustee and the successor Trustee, nominate with
respect to the applicable series or all series, as the case may be, a successor
Trustee which shall be deemed appointed as successor Trustee with respect to the
applicable series unless within ten days after such nomination the Company
objects thereto, in which case the Trustee so removed or any Holder of
Securities of the applicable series who has been a bona fide holder of a
Security or the applicable series for at least six months may, subject to the
provisions of Section 5.09 on behalf of himself and all others similarly
situated, petition any court of competent jurisdiction for the appointment of a
successor Trustee with respect to such series.

      (d)   If at any time:

            (1) the Trustee shall fail to comply with Section 310(b) of the
      Trust Indenture Act pursuant to Section 6.08 hereof after written request
      therefor by the Company or by any Holder who has been a bona fide Holder
      of a Security for at least six months, unless the Trustee's duty to resign
      is stayed in accordance with the provisions of Section 310(b) of the Trust
      Indenture Act, or

            (2) the Trustee shall cease to be eligible under Section 6.09 and
      shall fail to resign after written request therefor by the Company or by
      any such Holder, or

            (3) the Trustee shall become incapable of acting, or a decree or
      order for relief by a court having jurisdiction in the premises shall have
      been entered in respect of the
<PAGE>   41
                                                                              34


      Trustee in an involuntary case under the Federal bankruptcy laws, as now
      or hereafter constituted, or any other applicable Federal or State,
      bankruptcy, insolvency or similar law; or a decree or order by a court
      having jurisdiction in the premises for the appointment of a receiver or
      custodian or liquidator or trustee or assignee in bankruptcy or insolvency
      of the Trustee or of its property, or for the winding up of its affairs
      shall have been entered, or

            (4) the Trustee shall commence a voluntary case under the Federal
      bankruptcy laws, as now or hereafter constituted, or any other applicable
      Federal or State bankruptcy, insolvency or similar law, or shall consent
      to the appointment of a receiver or custodian or liquidator or trustee or
      assignee in bankruptcy or insolvency of it or of its property, or shall
      make an assignment for the benefit of creditors, or shall fail generally
      to pay its debts as they become due, or corporate action shall be taken by
      the Trustee in furtherance of any such action,

then, in any such case, (i) the Company by a Board Resolution may remove the
Trustee, or (ii) subject to Section 5.09, any Holder who has been a bona fide
Holder of a Security for at least six months may, on behalf of himself and all
others similarly situated, petition any court of competent jurisdiction for the
removal of the Trustee and the appointment of a successor Trustee.

      (e) If the Trustee shall resign, be removed or become incapable of acting,
or if a vacancy shall occur in the office of Trustee for any cause, with respect
to the Securities of one or more series, the Company, by a Board Resolution,
shall promptly appoint a successor Trustee to the vacated office. If, within one
year after such resignation, removal or incapability, or the occurrence of such
vacancy, a successor Trustee with respect to the Securities of any series shall
be appointed by Act of the Holders of a majority in principal amount of the
Outstanding Securities of such series delivered to the Company and the retiring
Trustee, the successor Trustee so appointed shall, forthwith upon its acceptance
of such appointment, become the successor Trustee with respect to the Securities
of such series and supersede the successor Trustee appointed by the Company. If
no successor Trustee shall have been so appointed by the Company or the Holders
and accepted appointment in the manner hereinafter provided, any Holder who has
been a bona fide Holder of a Security of such series for at least six months
may, on behalf of himself and all others similarly situated, petition any court
of competent jurisdiction for the appointment of a successor Trustee with
respect to the Securities of such series.

      (f) The Company shall give notice of each resignation and each removal of
the Trustee with respect to the Securities of any series and each appointment of
a successor Trustee with respect to the Securities of any series by mailing
written notice of such event by first-class mail, postage prepaid, to the
Holders of Securities of such series as their names and addresses appear in the
Security Register. Each notice shall include the name of the successor Trustee
with respect to the Securities of such series and the address of its Corporate
Trust Office.

      Section 6.11.     Acceptance of Appointment by Successor.

      Every successor Trustee appointed hereunder shall execute, acknowledge and
deliver to the Company and to the retiring Trustee an instrument accepting such
appointment, and thereupon the resignation or removal of the retiring Trustee
shall become effective and such
<PAGE>   42
                                                                              35


successor Trustee, without any further act, deed or conveyance, shall become
vested with all the rights, powers, trusts and duties of the retiring Trustee;
but, on request of the Company or the successor Trustee, such retiring Trustee
shall, upon payment of its charges, execute and deliver an instrument
transferring to such successor Trustee all the rights, powers and trusts of the
retiring Trustee, and shall duly assign, transfer and deliver to such successor
Trustee all property and money held by such retiring Trustee hereunder, subject
nevertheless to its lien, if any, provided for in Section 6.07. Upon request of
any such successor Trustee, the Company shall execute any and all instruments
for more fully and certainly vesting in and confirming to such successor Trustee
all such rights, powers and trusts.

      In case of the appointment hereunder of a successor Trustee with respect
to the Securities of one or more (but not all) series, the Company, the
predecessor Trustee and each successor Trustee with respect to the Securities of
any applicable series shall execute and deliver an indenture supplemental hereto
which shall contain such provisions as shall be deemed necessary or desirable to
confirm that all the rights, powers, trusts and duties of the predecessor
Trustee with respect to the Securities of any series as to which the predecessor
Trustee is not retiring shall continue to be vested in the predecessor Trustee,
and shall add to or change any of the provisions of this Indenture as shall be
necessary to provide for or facilitate the administration of the trusts
hereunder by more than one trustee, it being understood that nothing herein or
in such supplemental indenture shall constitute such trustees, co-trustees of
the same trust and that each trustee shall be trustee of a trust or trusts
hereunder separate and apart from any trust or trusts hereunder administered by
any other such trustee.

      No successor Trustee shall accept its appointment unless at the time of
such acceptance such successor Trustee shall be qualified and eligible under
this Article.

      Section 6.12.     Merger, Conversion, Consolidation or Succession to
Business.

      Any corporation into which the Trustee may be merged or converted or with
which it may be consolidated, or any corporation resulting from any merger,
conversion or consolidation to which the Trustee shall be a party, or any
corporation succeeding to all or substantially all of the corporate trust
business of the Trustee, shall be the successor of the Trustee hereunder,
provided such corporation shall be otherwise qualified and eligible under this
Article, without the execution or filing of any paper or any further act on the
part of any of the parties hereto. In case any Security shall have been
authenticated, but not delivered, by the Trustee then in office, any successor
by merger, conversion or consolidation to such authenticating Trustee may adopt
such authentication and deliver the Securities so authenticated with the same
effect as if such successor Trustee had itself authenticated such Securities.

      Section 6.13.     Preferential Collection of Claims Against Company.

      (a) Subject to Subsection (b) of this Section, if the Trustee shall be or
shall become a creditor, directly or indirectly, secured or unsecured, of the
Company within three months prior to a default, as defined in Subsection (e) of
this Section, or subsequent to such a default, then, unless and until such
default shall be cured, the Trustee shall set apart and hold in a special
account for the benefit of the Trustee individually, the Holders of the
Securities and the holders of other indenture securities, as defined in
Subsection (c) of this Section:
<PAGE>   43
                                                                              36


            (1) an amount equal to any and all reductions in the amount due and
      owing upon any claim as such creditor in respect of principal or interest,
      effected after the beginning of such three-month period and valid as
      against the Company and its other creditors, except any such reduction
      resulting from the receipt or disposition of any property described in
      paragraph (2) of this Subsection, or from the exercise of any right of
      set-off which the Trustee could have exercised if a petition in bankruptcy
      had been filed by or against the Company upon the date of such default;
      and

            (2) all property received by the Trustee in respect of any claim as
      such creditor, either as security therefor, or in satisfaction or
      composition thereof, or otherwise, after the beginning of such three-month
      period, or an amount equal to the proceeds of any such property, if
      disposed of, subject, however, to the rights, if any, of the Company and
      its other creditors in such property or such proceeds.

      Nothing herein contained, however, shall affect the right of the Trustee

                  (A) to retain for its own account (i) payments made on account
            of any such claim by any Person (other than the Company) who is
            liable thereon, and (ii) the proceeds of the bona fide sale of any
            such claim by the Trustee to a third Person, and (iii) distributions
            made in cash, securities or other property in respect of claims
            filed against the Company in bankruptcy or receivership or in
            proceedings for reorganization pursuant to the Federal bankruptcy
            laws, as now or hereafter constituted, or any other Federal or State
            bankruptcy, insolvency or similar law;

                  (B) to realize, for its own account, upon any property held by
            it as security for any such claim, if such property was so held
            prior to the beginning of such three-month period;

                  (C) to realize, for its own account, but only to the extent of
            the claim hereinafter or mentioned, upon any property held by it as
            security for any such claim, if such claim was created after the
            beginning of such three-month period and such property was received
            as security therefor simultaneously with the creation thereof, and
            if the Trustee shall sustain the burden of proving that at the time
            such property was so received the Trustee had no reasonable cause to
            believe that a default as defined in Subsection (c) of this Section
            would occur within three months; or

                  (D) to receive payment on any claim referred to in paragraph
            (B) or (C), against the release of any property held as security for
            such claim as provided in paragraph (B) or (C), as the case may be,
            to the extent of the fair value of such property.

      For the purposes of paragraphs (B), (C) and (D), property substituted
after the beginning of such three-month period for property held as security at
the time of such substitution shall, to the extent of the fair value of the
property released, have the same status as the property released, and, to the
extent that any claim referred to in any of such paragraphs is created in
renewal of or
<PAGE>   44
                                                                              37


in substitution for or for the purpose of repaying or refunding any pre-existing
claim of the Trustee as such creditor, such claim shall have the same status as
such pre-existing claim.

      If the Trustee shall be required to account, the funds and property held
in such special account and the proceeds thereof shall be apportioned between
the Trustee, the Holders and the holders of other indenture securities in such
manner that the Trustee, the Holders and the holders of other indenture
securities realize, as a result of payments from such special account and
payments of dividends on claims filed against the Company in bankruptcy or
receivership or in proceedings for reorganization pursuant to the Federal
bankruptcy laws, as now or hereafter constituted, or any other applicable
Federal or State bankruptcy, insolvency or similar law, the same percentage of
their respective claims, figured before crediting to the claim of the Trustee
anything on account of the receipt by it from the Company of the funds and
property in such special account and before crediting to the respective claims
of the Trustee and the Holders and the holders of other indenture securities
dividends on claims filed against the Company in bankruptcy or receivership or
in proceedings for reorganization pursuant to the Federal bankruptcy laws, as
now or hereafter constituted, or any other applicable Federal or State
bankruptcy, insolvency or similar law, but after crediting thereon receipts on
account of the indebtedness represented by their respective claims from all
sources other than from such dividends and from funds and property so held in
such special account. As used in this paragraph, with respect to any claim, the
term "dividends" shall include any distribution with respect to such claim, in
bankruptcy or receivership or proceedings for reorganization pursuant to the
Federal bankruptcy laws, as now or hereafter constituted, or any other
applicable Federal or State bankruptcy, insolvency or similar law, whether such
distribution is made in cash, securities, or other property, but shall not
include any such distribution with respect to the secured portion, if any, of
such claim. The court in which such bankruptcy, receivership or proceedings for
reorganization is pending shall have jurisdiction (i) to apportion between the
Trustee and the Holders and the holders of other indenture securities, in
accordance with the provisions of this paragraph, the funds and property held in
such special account and proceeds thereof, or (ii) in lieu of such
apportionment, in whole or in part, to give to the provisions of this paragraph
due consideration in determining the fairness of the distributions to be made to
the Trustee and the Holders and the holders of other indenture securities with
respect to their respective claims, in which event it shall not be necessary to
liquidate or to appraise the value of any securities or other property held in
such special account or as security for any such claim, or to make a specific
allocation of such distributions as between the secured and unsecured portions
of such claims, or otherwise to apply the provision of this paragraph as a
mathematical formula.

      Any Trustee which has resigned or been removed after the beginning of such
three-month period shall be subject to the provisions of this Subsection as
though such resignation or removal had not occurred. If any Trustee has resigned
or been removed prior to the beginning of such three-month period, it shall be
subject to the provisions of this Subsection if and only if the following
conditions exist:

                        (i) the receipt of property or reduction of claim, which
                  would have given rise to the obligation to account, if such
                  Trustee had continued as Trustee, occurred after the beginning
                  of such three-months period; and
<PAGE>   45
                                                                              38


                        (ii) such receipt of property or reduction of claim
                  occurred within three months after such resignation or
                  removal.

      (b)   There shall be excluded from the operation of Subsection (a) of this
Section a creditor relationship arising from

            (1) the ownership or acquisition of securities issued under any
      indenture, or any securities or securities having a maturity of one year
      or more at the time of acquisition by the Trustee;

            (2) advances authorized by a receivership or bankruptcy court of
      competent jurisdiction, or by this Indenture, for the purpose of
      preserving any property which shall at any time be subject to the lien of
      this Indenture or of discharging tax liens or other prior liens or
      encumbrances thereon, if notice of such advances and of the circumstances
      surrounding the making thereof is given to the Holders at the time and in
      the manner provided in this Indenture;

            (3) disbursements made in the ordinary course of business in the
      capacity of trustee under an indenture, transfer agent, registrar,
      custodian, paying agent, fiscal agent or depositary, or other similar
      capacity;

            (4) an indebtedness created as a result of services rendered or
      premises rented; or an indebtedness created as a result of goods or
      securities sold in a cash transaction as defined in Subsection (c) of this
      Section;

            (5) the ownership of stock or of other securities of a corporation
      organized under the provisions of Section 25(a) of the Federal Reserve
      Act, as amended, which is directly or indirectly a creditor of the
      Company; or

            (6) the acquisition, ownership, acceptance or negotiation of any
      drafts, bills of exchange, acceptances or obligations which fall within
      the classification of self-liquidating paper as defined in Subsection (c)
      of this Section.

      (c)   For the purpose of this Section only:

            (1) The term "default" means any failure to make payment in full of
      the principal of or interest on any of the Securities or upon the other
      indenture securities when and as such principal or interest becomes due
      and payable.

            (2) The term "other indenture securities" means securities upon
      which the Company is an obligor outstanding under any other indenture (i)
      under which the Trustee is also trustee, (ii) which contains provisions
      substantially similar to the provisions of this Section, and (iii) under
      which a default exists at the time of the apportionment of the funds and
      property held in such special account.

            (3) The term "cash transaction" means any transaction in which full
      payment for goods or
<PAGE>   46
                                                                              39


      securities sold is made within seven days after delivery of the goods or
      securities in currency or in checks or other orders drawn upon banks or
      bankers and payable upon demand.

            (4) The term "self-liquidating paper" means any draft, bill of
      exchange, acceptance or obligation which is made, drawn, negotiated or
      incurred by the Company for the purpose of financing the purchase,
      processing, manufacturing, shipment, storage or sale of goods, wares or
      merchandise and which is secured by documents evidencing title to,
      possession of, or a lien upon, the goods, wares or merchandise or the
      receivables or proceeds arising from the sale of the goods, wares or
      merchandise previously constituting the security, provided the security is
      received by the Trustee simultaneously with the creation of the creditor
      relationship with the Company arising from the making, drawing,
      negotiating or incurring of the draft, bill of exchange, acceptance or
      obligation.

            (5)   The term "Company" means any obligor upon the Securities.

      Section 6.14.     Appointment of Authenticating Agent.

      At any time when any of the Securities remain Outstanding the Trustee may
appoint an Authenticating Agent or Agents which shall be authorized to act on
behalf of the Trustee to authenticate Securities issued upon exchange, transfer
or partial redemption thereof or pursuant to Section 3.06, and Securities so
authenticated shall be entitled to the benefits of this Indenture and shall be
valid and obligatory for all purposes as if authenticated by the Trustee
hereunder. Wherever reference is made in this Indenture to the authentication
and delivery of Securities by the Trustee or the Trustee's certificate of
authentication, such reference shall be deemed to include authentication and
delivery on behalf of the Trustee by an Authenticating Agent and a certificate
of authentication executed on behalf of the Trustee by an Authenticating Agent.
Each Authenticating Agent shall be acceptable to the Company and shall at all
times be a bank or trust company or corporation organized and doing business and
in good standing under the laws of the United States of America, or of any
State, authorized under such laws to act as Authenticating Agent, having a
combined capital and surplus of not less than $1,500,000 and subject to
supervision or examination by Federal or State authorities. If such
Authenticating Agent publishes reports of condition at least annually, pursuant
to law or to the requirements of the aforesaid supervising or examining
authority, then for the purposes of this Section, the combined capital and
surplus of such Authenticating Agent shall be deemed to be its combined capital
and surplus as set forth in its most recent report of condition so published. In
case at any time an Authenticating Agent shall cease to be eligible in
accordance with the provisions of this Section, such Authenticating Agent shall
resign immediately in the manner and with the effect specified in this Section.

      Any corporation into which an Authenticating Agent may be merged or
converted or with which it may be consolidated, or any corporation resulting
from any merger, conversion or consolidation to which such Authenticating Agent
shall be a party, or any corporation succeeding to the corporate agency or
corporate trust business of an Authenticating Agent, shall continue to be an
Authenticating Agent without the execution or filing of any paper or any further
act on the part of the Trustee or the Authenticating Agent.
<PAGE>   47
                                                                              40


      An Authenticating Agent may at any time resign by giving written notice of
resignation to the Trustee and to the Company. The Trustee may at any time
terminate the agency of an Authenticating Agent by giving written notice of
termination to such Authenticating Agent and to the Company. Upon receiving such
a notice of resignation or upon such a termination, or in case at any time such
Authenticating Agent shall cease to be eligible in accordance with the
provisions of this Section, the Trustee may appoint a successor Authenticating
Agent which shall be acceptable to the Company and shall mail notice of such
appointment to all Holders, as their names and addresses appear on the Security
Register. Any successor Authenticating Agent upon acceptance of its appointment
hereunder shall become vested with all the rights, powers and duties of its
predecessor hereunder, with like effect as if originally named as an
Authenticating Agent herein. No successor Authenticating Agent shall be
appointed unless eligible under the provisions of this Section.

      The Trustee agrees to pay to each Authenticating Agent from time to time
reasonable compensation for its services under this Section, and the Trustee
shall be entitled to be reimbursed for such payments, subject to the provisions
of Section 6.07.

      If an appointment is made pursuant to this Section, the Securities shall
have endorsed thereon, in addition to the Trustee's Certificate, an alternate
Trustee's Certificate in the following form:

      This is one of the Debentures described in the within-mentioned Indenture.

                                          Citibank, N.A.,
                                                      as Trustee



                                    By
                                      ----------------------------------
                                                Authenticating Agent

                                    By
                                      ----------------------------------
                                                Authorized Officer



                                    Dated:
                                           -----------------------------



                                  ARTICLE SEVEN

                  HOLDER'S LISTS AND REPORTS BY TRUSTEE AND COMPANY

      Section 7.01. Company to Furnish Trustee Names and Addresses of Holders.

      The Company will furnish or cause to be furnished to the Trustee
<PAGE>   48
                                                                              41


            (a) semi-annually, (and not more than 15 days after each Regular
      Record Date of each series of Securities having such a Regular Record
      Date), a list, in such form as the Trustee may reasonable require, of the
      names and addresses of the Holders as of such Regular Record Date, and

            (b) at such other times as the Trustee may request in writing,
      within 30 days after the receipt by the Company of any such request, a
      list of similar form and content as of a date not more than 15 days prior
      to the time such list is furnished,

excluding from any such list names and addresses received by the Trustee in the
capacity of Security Registrar if the Trustee is then acting in such capacity.

      Section 7.02.     Preservation of Information:  Communications to Holders.

      (a) The Trustee shall preserve, in as current a form as is reasonably
practicable, the names and addresses of Holders contained in the most recent
list furnished to the Trustee as provided in Section 7.01 and the names and
addresses of Holders received by the Trustee in the capacity of Security
Registrar if the Trustee is then acting in such capacity. The Trustee may
destroy any list furnished to it as provided in Section 7.01 upon receipt of a
new list so furnished.

      (b) If three or more Holders (hereinafter referred to as "applicants")
apply in writing to the Trustee, and furnish to the Trustee reasonable proof
that each such applicant has owned a Security for a period of at least six
months preceding the date of such application, and such application states that
the applicants desire to communicate with other Holders with respect to their
rights under this Indenture or under the Securities and is accompanied by a copy
of the form of proxy or other communication which such applicants propose to
transmit, then the Trustee shall, within five business days after the receipt of
such application, at its election, either

                        (i)   afford such applicants access to the information
                  preserved at the time by the Trustee in accordance with
                  Section 7.02(a), or

                        (ii) inform such applicants as to the approximate number
                  of Holders whose names and addresses appear in the information
                  preserved at the time by the Trustee in accordance with
                  Section 7.02(a), and as to the approximate cost of mailing to
                  such Holders the form of proxy or other communication, if any,
                  specified in such application.

      If the Trustee shall elect not to afford such applicants access to such
information, the Trustee shall, upon the written request of such applicants,
mail to each Holder whose name and address appears in the information preserved
at the time by the Trustee in accordance with Section 7.02(a), a copy of the
form of proxy or other communication which is specified in such request, with
reasonable promptness after a tender to the Trustee of the material to be mailed
and of payment, or provision for the payment, of the reasonable expenses of
mailing, unless within five days after such tender, the Trustee shall mail to
such applicants and file with the Commission, together with a copy of the
material to be mailed, a written statement to the effect that, in the opinion of
the Trustee, such mailing would be contrary to the best interests of the Holders
or would be in violation of applicable law. Such written statement shall specify
the basis of such opinion. If the Commission, after opportunity for a hearing
upon the objections
<PAGE>   49
                                       42


specified in the written statement so filed, shall enter an order refusing to
sustain any of such objections or if, after the entry of an order sustaining one
or more of such objections, the Commission shall find, after notice and
opportunity for hearing, that all the objections so sustained have been met and
shall enter an order so declaring, the Trustee shall mail copies of such
material to all such Holders with reasonable promptness after the entry of such
order and the renewal of such tender; otherwise the Trustee shall be relieved of
any obligation or duty to such applicants respecting their application.

      (c) Every Holder of Securities, by receiving and holding the same, agrees
with the Company and the Trustee that neither the Company nor the Trustee nor
any Authenticating Agent nor any Paying Agent nor any Security Registrar shall
be held accountable by reason of the disclosure of any such information as to
the names and addresses of the Holders in accordance with Section 7.02(b),
regardless of the source from which such information was derived, and that the
Trustee shall not be held accountable by reason of mailing any material pursuant
to a request made under Section 7.02(b).

      Section 7.03.     Reports by Trustee.

      (a) Within 60 days after November 1 of each year commencing with the year
2002, the Trustee shall transmit by mail to all Holders, as their names and
addresses appear in the Security Register, a brief report dated as of November 1
with respect to any of the following events which may have occurred within the
prior 12 months (but if no such event has occurred within such period no report
need be transmitted):

            (1)   any change to its eligibility under Section 6.09 and its
      qualifications under Section 6.08;

            (2) the creation of any material change to a relationship specified
      in Section 310(b)(1) through Section 310(b)(10) of the Trust Indenture
      Act;

            (3) the character and amount of any advances (and if the Trustee
      elects so to state the circumstances surrounding the making thereof) made
      by the Trustee (as such) which remain unpaid on the date of such report,
      and for the reimbursement of which it claims or may claim a lien or
      charge, prior to that of the Debentures, on any property or funds held or
      collected by it as Trustee, except that the Trustee shall not be required
      (but may elect) to report such advances if such advances so remaining
      unpaid aggregate not more than 1/2 of 1% of the principal amount of the
      Outstanding Securities on the date of such report;

            (4) any change to the amount, interest rate and maturity date of all
      other indebtedness owing by the Company (or by any other obligor on the
      Securities) to the Trustee in its individual capacity, on the date of such
      report, with a brief description of any property held as collateral
      security therefor, except an indebtedness based upon a creditor
      relationship arising in any manner described in Section 6.13(b)(2), (3),
      (4) or (6);

            (5) any change to the property and funds, if any, physically in the
      possession of the Trustee as such on the date of such report;
<PAGE>   50
                                                                              43


            (6)   any additional issue of Securities which the Trustee has not
      previously reported; and

            (7) any action taken by the Trustee in the performance of its duties
      hereunder which it has not previously reported and which in its opinion
      materially affects the Securities, except action in respect of a default,
      notice of which has been or is to be withheld by the Trustee in accordance
      with Section 6.02.

      (b) The Trustee shall transmit by mail to all Holders, as their names and
addresses appear in the Security Register, a brief report with respect to the
character and amount of any advances (and if the Trustee elects so to state, the
circumstances surrounding the making thereof) made by the Trustee (as such)
since the date of the last report transmitted pursuant to Subsection (a) of this
Section (or if no such report has yet been so transmitted, since the date of
execution of this instrument) for the reimbursement of which it claims or may
claim a lien or charge, prior to that of the Securities, on property or funds
held or collected by it as Trustee, and which it has not previously reported
pursuant to this Subsection, except that the Trustee shall not be required (but
may elect) to report such advances if such advances remaining unpaid at any time
aggregate 10% or less of the principal amount of the Outstanding Securities at
such time, such report to be transmitted within 90 days after such time.

      (c) A copy of each such report shall, at the time of such transmission to
Holders, be filed by the Trustee with each securities exchange upon which the
Securities are listed and also with the Commission. The Company will notify the
Trustee when the Securities are listed on any securities exchange.

      Section 7.04.     Reports by Company.

      The Company will

            (1) file with the Trustee, within 15 days after the Company is
      required to file the same with the Commission, copies of the annual
      reports and of the information, documents and other reports (or copies of
      such portions of any of the foregoing as the Commission may from time to
      time by rules and regulations prescribe) which the Company may be required
      to file with the Commission pursuant to Section 13 or Section 15(d) of the
      Securities Exchange Act of 1934; or, if the Company is not required to
      file information, documents or reports pursuant to either of said
      Sections, then it will file with the Trustee and the Commission, in
      accordance with rules and regulations prescribed from time to time by the
      Commission, such of the supplementary and periodic information, documents
      and reports which may be required pursuant to Section 13 of the Securities
      Exchange Act of 1934 in respect of a security listed and registered on a
      National Securities Exchange as may be prescribed from time to time in
      such rules and regulations;

            (2) file with the Trustee and the Commission, in accordance with
      rules and regulations prescribed from time to time by the Commission, such
      additional information, documents and reports with respect to compliance
      by the Company with the conditions
<PAGE>   51
                                                                              44


      and covenants of this Indenture as may be required from time to time by
      such rules and regulations; and

            (3) transmit by mail to all Holders, as their names and addresses
      appear in the Security Registrar, within 30 days after the filing thereof
      with the Trustee, such summaries of any information, documents and reports
      required to be filed by the Company pursuant to paragraphs (1) and (2) of
      this Section as may be required by rules and regulations prescribed from
      time to time by the Commission.

            Delivery of such reports, information and documents to the Trustee
is for informational purposes only and the Trustee's receipt of such shall not
constitute constructive notice of any information contained therein or
determinable from information contained therein, including the Company's
compliance with any of its covenants hereunder (as to which the Trustee is
entitled to rely exclusively on Officers' Certificates).

                                  ARTICLE EIGHT

                CONSOLIDATION, MERGER, SALE, CONVEYANCE OR LEASE

      Section 8.01.     Consolidations and Mergers of Company and Conveyances
Permitted Subject to Certain Conditions.

      The Company may consolidate with, or sell or convey all or substantially
all of its assets to, or merge with or into any other corporation, provided that
in any such case, (i) either the Company shall be the continuing corporation, or
the successor corporation shall be a corporation organized and existing under
the laws of the United States of America or a State thereof and such successor
corporation shall expressly assume the due and punctual payment of the principal
of and interest on all the Securities, according to their tenor and the due and
punctual performance and observance of all of the covenants and conditions of
this Indenture to be performed by the Company by supplemental indenture
satisfactory to the Trustee, executed and delivered to the Trustee by such
corporation, and (ii) the Company or such successor corporation, as the case may
be, shall not, immediately after such merger or consolidation, or such sale or
conveyance, be in default in the performance of any such covenant or condition.

      Section 8.02.     Rights and Duties of Successor Corporation.

      In case of any such consolidation, merger, sale or conveyance and upon any
such assumption by the successor corporation, such successor corporation shall
succeed to and be substituted for the Company, with the same effect as if it had
been named herein as the Company, and the predecessor corporation shall be
relieved of any obligation under this Indenture and the Securities and, in the
event of such sale or conveyance may be dissolved and/or liquidated. Such
successor corporation thereupon may cause to be signed, and may issue either in
its own name or in the name of the Company, any or all of the Securities
issuable hereunder which theretofore shall not have been signed by the Company
and delivered to the Trustee; and, upon the order of such successor corporation,
instead of the Company, and subject to all the terms, conditions and limitations
in this Indenture prescribed, the Trustee shall authenticate and shall deliver
any Securities which previously shall have been signed and
<PAGE>   52
                                       45


delivered by the officers of the Company to the Trustee for authentication, and
any Securities which such successor corporation thereafter shall cause to be
signed and delivered to the Trustee for that purpose. All the Securities so
issued shall in all respects have the same legal rank and benefit under this
Indenture as the Securities theretofore or thereafter issued in accordance with
the terms of this Indenture as though all of such Securities had been issued at
the date of the execution hereof.

      In case of any such consolidation, merger, sale or conveyance such changes
in phraseology and form (but not in substance) may be made in the Securities
thereafter to be issued as may be appropriate.

      Section 8.03.     Securities to be Secured in Certain Events.

      If, after giving effect to any such consolidation or merger of the Company
with or into any other corporation, or after giving effect to any sale or
conveyance of the property of the Company as an entirety or substantially as an
entirety to any other corporation, the corporation formed by or resulting or
surviving therefrom or which shall have received such property would have
outstanding any Debt (as defined in Section 10.08) secured by any Mortgage (as
defined in Section 10.08) on any Principal Property, or on any shares of stock
or Debt (as defined in Section 10.08) of any Restricted Subsidiary, which such
Debt could not at such time be incurred by such corporation under Section 10.08
without equally and ratably securing the Securities, the Company, prior to such
consolidation, merger, sale or conveyance, will secure the Outstanding
securities hereunder, equally and ratably with (or prior to) the Debt (as
defined in Section 10.08) secured by such Mortgage.

      Section 8.04.     Officers' Certificate and Opinion of Counsel.

      The Trustee, subject to the provisions of Section 6.01, shall be provided
with an Officers' Certificate and an Opinion of Counsel as conclusive evidence
that any such consolidation, merger, sale or conveyance, and any such
assumption, complies with the provisions of this Article Eight.

      Section 8.05.     Limitation on Lease of Properties as Entirety.

      The Company shall not lease its properties and assets substantially as an
entirety to any Person.

                                     ARTICLE NINE

                               SUPPLEMENTAL INDENTURES

      Section 9.01. Supplemental Indentures without Consent of Holders. The
Company, when authorized by a Board Resolution, and the Trustee may from time to
time and at any time enter into an indenture or indentures supplemental hereto
for one or more of the following purposes:
<PAGE>   53
                                                                              46


            (a) to evidence the succession of another corporation to the
      Company, or successive successions, and the assumption by the successor
      corporation of the covenants, agreements and obligations of the Company
      hereunder; or

            (b) to convey, transfer, assign, mortgage or pledge to the Trustee
      as security for the Securities any property or assets which the Company
      may desire or may be required to convey, transfer, assign, mortgage or
      pledge in accordance with the provisions of Section 8.03 or Section 10.08;
      or

            (c) to add to the covenants of the Company such further covenants,
      restrictions or conditions for the protection of the Holders of all or any
      series of Securities (and if such covenants are to be for the benefit of
      less than all series of Securities stating that such covenants are
      expressly being included solely for the benefit of such series) as the
      Board of Directors of the Company and the Trustee shall consider to be for
      the protection of the Holders of such Securities, and to make the
      occurrence, or the occurrence and continuance, of a default in any of such
      additional covenants, restrictions or conditions a default or an Event of
      Default permitting the enforcement of all or any of the several remedies
      provided in this Indenture as herein set forth; provided, however, that in
      respect of any such additional covenant, restriction or condition such
      supplemental indenture may provide for a particular period of grace after
      default (which period may be shorter or longer than that allowed in the
      case of other defaults) or may provide for an immediate enforcement upon
      such default or may limit the remedies available to the Trustee upon such
      default; or

            (d) to provide for the issuance under this Indenture of Securities
      in coupon form (including Securities registrable as to principal only) and
      to provide for exchangeability of such Securities with the Securities
      issued hereunder in fully registered form and to make all appropriate
      changes for such purpose; or

            (e)   to establish the form or terms of Securities of any series as
      permitted by Sections 2.01 and 3.01; or

            (f) to cure any ambiguity or to correct or supplement any provision
      contained herein or in any supplemental indenture which may be defective
      or inconsistent with any other provision contained herein or in any
      supplemental indenture, or to make such other provisions in regard to
      matters or questions arising under this Indenture which shall not
      adversely affect the interests of any Holder; or

            (g) to evidence and provide for the acceptance of appointment
      hereunder by a successor trustee with respect to the Securities of one or
      more series and to add to or change any of the provisions of this
      Indenture as shall be necessary to provide for or facilitate the
      administration of the trusts hereunder by more than one trustee, pursuant
      to the requirements of Section 6.11.

      The Trustee is hereby authorized to join with the Company in the execution
of any such supplemental indenture, to make any further appropriate agreements
and stipulations which may be therein contained and to accept the conveyance,
transfer, assignment, mortgage or pledge of
<PAGE>   54
                                                                              47


any property thereunder, but the Trustee shall not be obligated to, but may in
its discretion, enter into any such supplemental indenture which affects the
Trustee's own rights, duties or immunities under this Indenture or otherwise.

      Any supplemental indenture authorized by the provisions of this Section
9.01 may be executed by the Company and the Trustee without the consent of the
Holders of any of the Securities at the time Outstanding, notwithstanding any of
the provisions of Section 9.02.

      Section 9.02. Supplemental Indentures with Consent of Holders. With the
consent (evidenced as provided in Section 1.04) of the Holders of not less than
50% in aggregate principal amount of the Outstanding Securities of all series
affected by such supplemental indenture (voting as one class), the Company, when
authorized by a Board Resolution, and the Trustee may from time to time and at
any time enter into an indenture or indentures supplemental hereto for the
purpose of adding any provisions to or changing in any manner or eliminating any
of the provisions of this Indenture or of any supplemental indenture or of
modifying in any manner or eliminating any of the provisions of this Indenture
or of any supplemental indenture or of modifying in any manner the rights of the
Holders of the Securities of each such series; provided, however, that no such
supplemental indenture shall (i) change the Stated Maturity of any Security, or
reduce the rate or change the time of payment of interest thereon, or reduce the
principal amount thereof or any premium thereon, or make the principal thereof
or interest or premium thereon payable in any coin or currency other than that
provided in the Securities or reduce the amount of the principal of an Original
Issue Discount Security that would be due and payable upon an acceleration of
the Maturity thereof pursuant to Section 5.02 or the amount thereof provable in
bankruptcy pursuant to Section 5.03 or impair the right to institute suit for
enforcement of any such payment on or after the Stated Maturity thereof (or, in
the case of redemption, on or after the Redemption Date), or adversely affect
the right of repayment, if any, at the option of the Holder without the consent
of the Holder of each Security so affected, or (ii) reduce the aforesaid
percentage of Securities, the Holders of which are required to consent to any
such supplemental indenture, or the Holders of which are required for any waiver
(of compliance with certain provisions of this Indenture or certain defaults
hereunder and their consequences) provided for in this Indenture, without the
consent of the Holder of each Security so affected. A supplemental indenture
which changes or eliminates any covenant or other provision of this Indenture
which has expressly been included solely for the benefit of one or more
particular series of Securities, or which modifies the rights of the Holders of
Securities of such series with respect to such covenant or other provision,
shall be deemed not to affect the rights under this Indenture of the Holders of
Securities of any other series.

      Upon the request of the Company, accompanied by a Board Resolution
authorizing the execution of any such supplemental indenture, and upon the
filing with the Trustee of evidence of the consent of Holders as aforesaid, the
Trustee shall join with the Company in the execution of such supplemental
indenture unless such supplemental indenture affects the Trustee's own rights,
duties or immunities under this Indenture or otherwise, in which case the
Trustee may in its discretion, but shall not be obligated to, enter into such
supplemental indenture.

      It shall not be necessary for the consent of the Holders under this
Section 9.02 to approve the particular form of any proposed supplemental
indenture, but it shall be sufficient if such consent shall approve the
substance thereof.
<PAGE>   55
                                                                              48


      Section 9.03. Compliance with Trust Indenture Act; Effect of Supplemental
Indentures. Any supplemental indenture executed pursuant to the provisions of
this Article Nine shall comply with the Trust Indenture Act of 1939, as then in
effect. Upon the execution of any supplemental indenture pursuant to the
provisions of this Article Nine, this Indenture shall be deemed to be modified
and amended in accordance therewith and the respective rights, limitations of
rights, obligations, duties and immunities under this Indenture of the Trustee,
the Company, and the Holders shall thereafter be determined, exercised and
enforced hereunder subject in all respects to such modifications and amendments
and all the terms and conditions of any such supplemental indenture shall be and
be deemed to be part of the terms and conditions of this Indenture for any and
all purposes.

      Section 9.04. Notation on Securities. Securities authenticated and
delivered after the execution of any supplemental indenture pursuant to the
provisions of this Article Nine may bear a notation in form approved by the
Trustee as to any matter provided for in such supplemental indenture. If the
Company or the Trustee shall so determine, new Securities of any series so
modified as to conform, in the opinion of the Trustee and the Board of
Directors, to any modification of this Indenture contained in any such
supplemental indenture may be prepared and executed by the Company,
authenticated by the Trustee and delivered in exchange for the Securities of
such series then Outstanding.

      Section 9.05.     Evidence of Compliance of Supplemental Indenture to be
Furnished Trustee.

      The Trustee, subject to the provisions of Section 6.01, shall be provided
with an Officers' Certificate and an Opinion of Counsel as conclusive evidence
that any supplemental indenture executed pursuant hereto complies with the
requirements of this Article Nine.

                                   ARTICLE TEN

                                    COVENANTS

      Section 10.01.    Payment of Principal and Interest.

      The Company will duly and punctually pay the principal of, premium, if
any, and interest on the Securities in accordance with the terms of the
Securities and this Indenture.

      Section 10.02.    Maintenance of Office or Agency.

      The Company shall maintain in the Borough of Manhattan, The City of New
York, an office or agency where Securities may be presented or surrendered for
payment and an office or agency where Securities may be surrendered for transfer
or exchange and where notices and demands to or upon the Company in respect of
the Securities and this Indenture may be served. The Corporate Trust Office of
the Trustee shall be such office of the Company in The City of New York, and the
Trustee shall be the agent of the Company for all of the foregoing purposes,
unless the Company shall designate and maintain some other office or agency for
such purposes and give the Trustee written notice of the location thereof. The
Company will give prompt written notice to the Trustee of any change in the
location of any such office or agency. If at any time the Company shall fail to
maintain any such required office or agency in the Borough of
<PAGE>   56
                                                                              49


Manhattan, The City of New York, the Corporate Trust Office of the Trustee shall
be conclusively deemed to be the agency of the Company for all such purposes.

      Section 10.03.    Money for Security Payments to be Held in Trust.

      If the Company shall at any time act as its own Paying Agent, it will, on
or before each due date of the principal of or premium, if any, or interest on,
any of the Securities, segregate and hold in trust for the benefit of the
Persons entitled thereto a sum sufficient to pay the principal or premium, if
any, or interest so becoming due until such sums shall be paid to such Persons
or otherwise disposed of as herein provided, and will promptly notify the
Trustee of its action or failure so to act.

      Whenever the Company shall have one or more Paying Agents it will, on or
prior to each due date of the principal of or interest on, any Securities,
deposit with a Paying Agent a sum sufficient to pay the principal or premium, if
any, or interest, so becoming due, such sum to be held in trust for the benefit
of the Persons entitled to such principal or premium, if any, or interest, and
(unless such Paying Agent is the Trustee) the Company will promptly notify the
Trustee of its action or failure so to act.

      The Company will cause each Paying Agent other than the Trustee to execute
and deliver to the Trustee an instrument in which such Paying Agent shall agree
with the Trustee, subject to the provisions of this Section, that such Paying
Agent will

            (1) hold all sums held by it for the payment of the principal of or
      premium, if any, or interest on Securities in trust for the benefit of the
      Persons entitled thereto until such sums shall be paid to such Persons or
      otherwise disposed of as herein provided;

            (2) give the Trustee notice of any default by the Company (or any
      other obligor upon the Securities) in the making of any payment of
      principal or premium, if any, or interest; and

            (3) at any time during the continuance of any such default, upon the
      written request of the Trustee, forthwith pay to the Trustee all sums so
      held in trust by such Paying Agent.

      The Company may at any time, for the purpose of obtaining the satisfaction
and discharge of this Indenture or for any other purpose, pay, or by Company
Order direct any Paying Agent to pay, to the Trustee all sums held in trust by
the Company or such Paying Agent, such sums to be held by the Trustee upon the
same trusts as those upon which such sums were held by the Company or such
Paying Agent; and, upon such payment by any Paying Agent to the Trustee, such
Paying Agent shall be released from all further liability with respect to such
money.

      Any money deposited with the Trustee or any Paying Agent, or then held by
the Company, in trust for the payment of the principal of or premium, if any, or
interest on any Security and remaining unclaimed for three years after such
principal or premium, if any or interest has become due and payable shall be
paid to the Company on Company Request, or (if then held by the Company) shall
be discharged from such trust; and the Holder of such Security
<PAGE>   57
                                                                              50


shall thereafter, as an unsecured general creditor, look only to the Company for
payment thereof, and all liability of the Trustee or such Paying Agent with
respect to such trust money, and all liability of the Company as trustee
thereof, shall thereupon cease; provided, however, that the Trustee or such
Paying Agent, before being required to make any such repayment, may at the
expense of the Company cause to be published once, in a newspaper published in
the English language, customarily published on each Business Day and of general
circulation in the Borough of Manhattan, The City of New York, notice that such
money remains unclaimed and that, after a date specified therein, which shall
not be less than 30 days from the date of such publication, any unclaimed less
than 30 days from the date of such publication, any unclaimed balance of such
money then remaining will be repaid to the Company.

      Section 10.04.    Payment of Taxes and Other Claims.

      The Company will pay or discharge or cause to be paid or discharged,
before the same shall become delinquent, (1) all taxes, assessments and
governmental charges levied or imposed upon the Company or any Subsidiary or
upon the income, profits or property of the Company or any Subsidiary, and (2)
all lawful claims for labor, materials and supplies which, if unpaid, might by
law become a lien upon the property of the Company or any Subsidiary; provided,
however, that the Company shall not be required to pay or discharge or cause to
be paid or discharged any such tax, assessment, charge or claim whose amount,
applicability or validity is being contested in good faith by appropriate
proceedings.

      Section 10.05.    Maintenance of Principal Properties.

      The Company will cause all Principal Properties to be maintained and kept
in good physical condition, repair and working order and supplied with all
necessary equipment and will cause to be made all necessary physical repairs,
renewals, replacements betterments and improvements thereof, all as in the
judgment of the Company may be necessary so that the business carried on in
connection therewith may be properly and advantageously conducted at all times;
provided, however, that nothing in this Section shall prevent or restrict the
sale, abandonment or other disposition of any of such properties if such section
is, in the judgment of the Company, desirable in the conduct of the business of
the Company and its Subsidiaries as a whole.

      Section 10.06.    Statement as to Default.

      The Company will deliver to the Trustee, on or before a date not more than
four months after the end of each fiscal year of the Company ending after the
date hereof, a statement (which shall not be deemed an Officers' Certificate and
need not conform with any of the provisions of Section 1.02) signed by the
principal executive officer, principal financial officer or principal accounting
officer of the Company and by the Treasurer or the Secretary or any Assistant
Treasurer or any Assistant Secretary the Company, stating that in the course of
the performance by the signers of their duties as officers of the Company and
based upon a review made under their supervision of the activities of the
Company during such year and of the Company's performance under this Indenture
they would normally obtain knowledge whether or not the Company is in default in
the performance of any covenant or agreement contained herein, stating whether
or not they have obtained knowledge that the Company is in default in the
performance
<PAGE>   58
                                                                              51


of any such covenant or agreement, and if so, specifying each such
default of which the signers have knowledge and the nature thereof. For purposes
of this Section, such compliance shall be determined without regard to any
period of grace or requirement of notice provided under this Indenture.

      The Company shall deliver to the Trustee, as soon as possible and in any
event within five days after the Company becomes aware of the occurrence of any
Event of Default or an event which, with notice or the lapse of time or both,
would constitute an Event of Default, an Officers' Certificate setting forth the
details of such Event of Default or default and the action which the Company
proposes to take with respect thereto.

      Section 10.07.    Corporate Existence.

      Subject to Article Eight, the Company will do or cause to be done all
things necessary to preserve and keep in full force and effect its corporate
existence and the rights (charter and statutory) and franchises of the Company
and any Subsidiary; provided, however, that the Company shall not be required to
preserve any such right or franchise if the Company shall determine that the
preservation thereof is no longer desirable in the conduct of the business of
the Company and its Subsidiaries as a whole.

      Section 10.08.    Limitation on Secured Debt.

      The Company will not itself, and will not permit any Restricted Subsidiary
to, incur, issue, assume or guarantee any notes, bonds, debentures or other
similar evidences of indebtedness (such Notes, bonds, debentures or other
similar evidences of indebtedness being hereinafter in this Article called
"Debt"), secured by pledge of, or mortgage or other lien on, any Principal
Property owned or leased by the Company or any Restricted Subsidiary, or any
shares of stock or Debt of any Restricted Subsidiary (pledges, mortgages and
other liens being hereinafter in this Article called "Mortgage" or "Mortgages"),
without effectively providing that the Securities (together with, if the Company
shall so determine, any other Debt of the Company or such Restricted Subsidiary
then existing or thereafter created which is not subordinated to the Securities)
shall be secured equally and ratably with (or prior to) such secured Debt, so
long as such secured Debt shall be so secured, unless, after giving effect
thereto, the aggregate amount of all such secured debt (not including secured
Debt permitted to be secured under clauses (1) to (7) below) plus the aggregate
"value" (as defined in Section 10.09) of all sale and leaseback transactions (as
defined in Section 10.09 but not including sale and leaseback transactions the
proceeds of which have been or will be applied in accordance with Section
10.09(2)) would not exceed [5]% of Consolidated Net Tangible Assets; provided,
however, that this Section shall not apply to, and there shall be excluded from
secured Debt in any computation under this Section, Debt secured by:

            (1) Mortgages on property of, or on any shares of stock or Debt of,
      the Company or a Restricted Subsidiary, existing on the date hereof;

            (2) Mortgages on property of, or on any shares of stock or Debt of,
      any corporation existing at the time such corporation becomes a Restricted
      Subsidiary;

<PAGE>   59
                                                                              52


            (3) Mortgages on property of a Restricted Subsidiary securing
      exclusively indebtedness of such Subsidiary owing to the Company or any
      other Restricted Subsidiary;

            (4) Mortgages in favor of the United States of America, or any State
      or agency thereof or of any foreign country, or any agency, department or
      other instrumentality thereof, to secure progress, advance or other
      payments pursuant to any contract or provision of any statute;

            (5) Mortgages on property, shares of stock for Debt existing at the
      time of acquisition thereof (including acquisition through merger or
      consolidation) or to secure the payment of all or any part of the purchase
      price or construction cost thereof or to secure any Debt incurred prior
      to, at the time of, or within 24 months after, the acquisition of such
      property or shares or Debt or the completion of any such construction for
      the purpose of financing all or any part of the purchase price or
      construction cost thereof;

            (6) Mortgages on property of the Company or a Restricted Subsidiary
      to secure the payment of all or any part of the costs of exploration,
      drilling, mining, or development thereof for the purpose of increasing the
      production and sale or other disposition of oil, gas or other minerals or
      any indebtedness incurred to provide funds for all or any such purposes;
      and

            (7) any extension, renewal or replacement (or successive extensions,
      renewals or replacements), as a whole or in part, of any Mortgage referred
      to in the foregoing clauses (1) to (6), inclusive; provided, that (i) such
      extension, renewal or replacement Mortgage shall be limited to all or a
      part of the same property, shares of stock or Debt that secured the
      Mortgage extended, renewal or replaced (plus improvements on such
      property) and (ii) the Debt secured by such Mortgage at such time is not
      increased.

      For purposes of this Section 10.08, the sale or other transfer of any
interest in property of the character commonly referred to as a "production
payment" shall not be deemed to create secured Debt.

      Section 10.09.    Limitation on Sales and Leasebacks.

      The Company will not itself, and it will not permit any Restricted
Subsidiary to, enter into any arrangement with any bank, insurance company or
other lender or investor (not including the Company or any Restricted
Subsidiary) or to which any such lender or investor is a party, providing for
the leasing by the Company or any such Restricted Subsidiary for a period,
including renewals, in excess of three years of any Principal Property owned or
leased by the Company or such Restricted Subsidiary which has been or is to be
sold or transferred, more than 120 days after the completion of construction and
commencement of full operation thereof, by the Company or any such Restricted
Subsidiary to such lender or investor or to any person to whom funds have been
or are to be advanced by such lender or investor on the security of such
Principal Property (herein referred to as a "sale and leaseback transaction")
unless either:
<PAGE>   60
                                                                              53


            (1) the Company or such Restricted Subsidiary could create Debt
      secured by a Mortgage pursuant to Section 10.08 on the Principal Property
      to be leased back equal in amount to the amount realized or to be realized
      upon such sale and leaseback transaction without equally and ratably
      securing the Securities, or

            (2) the Company within 120 days after the sale or transfer shall
      have been made by the Company or by any such Restricted Subsidiary;
      applies an amount equal to the value of the Principal Property so sold and
      leased back at the time of entering into such arrangement to the
      retirement of Funded Debt of the Company; provided, that the amount to be
      applied to the retirement of Funded Debt of the Company shall be reduced
      by (a) the principal amount of any Securities delivered within 120 days
      after such sale to the Trustee for retirement and cancellation, and (b)
      the principal amount of Funded Debt, other than Securities, voluntarily
      retired by the Company within 120 days after such sale. Notwithstanding
      the foregoing, no retirement referred to in this clause (2) may be
      effected by payment at maturity or pursuant to any mandatory sinking fund
      payment or any mandatory prepayment provision.

      As used in this Section 10.09, the term "value" shall mean, with respect
to a sale and leaseback transaction, as of any particular time an amount equal
to the greater of (i) the net proceeds of sale of the property leased pursuant
to such sale and leaseback transaction, or (ii) the fair value of such property
at the time of entering into such sale and leaseback transaction as determined
by the Board of Directors, in each case multiplied by a fraction of which the
numerator is the number of full years of remaining term of the lease (without
regard to renewal options) and the denominator is the full years of the full
term of the lease (without regard to renewal options).

      It is understood that transactions entered into pursuant to Section
168(f)(8) of the Internal Revenue Code, as amended, are not Debt secured by a
Mortgage within the meaning of Section 10.08 or sale and leaseback transactions
prohibited by this Section 10.09.

      Section 10.10.    Waiver of Certain Covenants.

      The Company may omit in any particular instance to comply with any
covenant or condition set forth in Section 10.04, 10.05 and 10.07 through 10.09
or any covenant added for the benefit of any series of Securities as
contemplated by Section 3.01, if before or after the time for such compliance
the Holders of at least a majority in principal amount of the Securities at the
time Outstanding shall, by Act of such Holders, waive such compliance in such
instance, but no such waiver shall extend to or affect such covenant or
condition except to the extent so expressly waived, and, until such waiver shall
become effective, the obligations of the Company and the duties of the Trustee
in respect of any such covenant or condition shall remain in full force and
effect.

      Section 10.11.    Calculation of Original Issue Discount.

      The Company shall file with the Trustee promptly at the end of each
calendar year (i) a written notice specifying the amount of original issue
discount (including daily rates and accrual periods) accrued on Outstanding
Securities as of the end of such year and (ii) such other specific
<PAGE>   61
                                                                              54


information relating to such original issue discount as may then be relevant
under the Internal Revenue Code of 1986, as amended from time to time.

                                 ARTICLE ELEVEN

                            REDEMPTION OF SECURITIES

      Section 11.01. Applicability of Article. The provisions of this Article
shall be applicable to the Securities of any series which are redeemable before
their maturity except as otherwise specified as contemplated by Section 3.01 for
Securities of such series.

      Section 11.02. Notice of Redemption; Selection of Securities. In case the
Company shall desire to exercise the right to redeem all, or, as the case may
be, any part of the Securities of any series in accordance with their terms, it
shall fix a date for redemption and shall mail or cause to be mailed a notice of
such redemption at least 30 and not more than 60 days prior to the date fixed
for redemption to the Holders of Securities of such series so to be redeemed as
a whole or in part at their last addresses as the same appear on the Security
Register. Such mailing shall be by first class mail. The notice if mailed in the
manner herein provided shall be conclusively presumed to have been duly given,
whether or not the Holder receives such notice. In any case, failure to give
such notice by mail or any defect in the notice to the Holder of any Security of
a series designated for redemption as a whole or in part shall not affect the
validity of the proceedings for the redemption of any other Security of such
series.

      Each such notice of redemption shall specify the date fixed for
redemption, the redemption price at which Securities of such series are to be
redeemed, the place or places of payment, that payment will be made upon
presentation and surrender of such Securities, that any interest accrued to the
date fixed for redemption will be paid as specified in said notice, and that on
and after said date any interest thereon or on the portions thereof to be
redeemed will cease to accrue. If less than all the Securities of a series are
to be redeemed the notice of redemption shall specify the numbers of the
Securities of that series to be redeemed. In case any Security of a series is to
be redeemed in part only, the notice of redemption shall state the portion of
the principal amount thereof to be redeemed and shall state that on and after
the date fixed for redemption, upon surrender of such Security, a new Security
or Securities of that series in principal amount equal to the unredeemed potion
thereof will be issued.

      On or before the redemption date specified in the notice of redemption
given as provided in this Section 11.02, the Company will deposit with the
Trustee or with one or more paying agents an amount of money sufficient to
redeem on the redemption date all the Securities or portions thereof so called
for redemption at the appropriate redemption price, together with accrued
interest to the date fixed for redemption.

      If all or less than all the Securities of a series are to be redeemed the
Company will give the Trustee notice not less than 60 days prior to the
redemption date as to the aggregate principal amount of Securities to be
redeemed and the Trustee shall select, in such manner as in its sole discretion
it shall deem appropriate, the Securities of that series or portions thereof (in
multiples of $1,000, except as otherwise set forth in the applicable form of
Security) to be redeemed.
<PAGE>   62
                                                                              55


      Section 11.03. Payment of Securities Called for Redemption. If notice of
redemption has been given as provided in Section 11.02 or Section 12.03, the
Securities or portions of Securities of the series with respect to which such
notice has been given shall become due and payable on the date and at the place
or places stated in such notice at the applicable redemption price, together
with any interest accrued to the date fixed for redemption, and on and after
said date (unless the Company shall default in the payment of such Securities at
the applicable redemption price, together with any interest accrued to said
date) any interest on the Securities or portions of Securities of any series so
called for redemption shall cease to accrue. On presentation and surrender of
such Securities at a place of payment in said notice specified, the said
Securities or the specified portions thereof shall be paid and redeemed by the
Company at the applicable redemption price, together with any interest accrued
thereon to the date fixed for redemption.

      Upon presentation of any Security redeemed in part only, the Company shall
execute and the Trustee shall authenticate and deliver to the Holder thereof, at
the expense of the Company, a new Security or Securities of such series, of
authorized denominations, in principal amount equal to the unredeemed portion of
the Security so presented.

                                 ARTICLE TWELVE

                                  SINKING FUNDS

      Section 12.01. Applicability of Article. The provisions of this Article
shall be applicable to any sinking fund for the retirement of Securities of a
series except as otherwise specified as contemplated by Section 3.01 for
Securities of such series.

      The minimum amount of any sinking fund payment provided for by the terms
of Securities of any series is herein referred to as a "mandatory sinking fund
payment", and any payment in excess of such minimum amount provided for by the
terms of Securities of any series is herein referred to as an "optional sinking
fund payment".

      Section 12.02. Satisfaction of Mandatory Sinking Fund Payments with
Securities. In lieu of making all or any part of any mandatory sinking fund
payment with respect to any Securities of a series in cash, the Company may at
its option (a) deliver to the Trustee Securities of that series theretofore
purchased or otherwise acquired by the Company, or (b) receive credit for the
principal amount of Securities of that series which have been previously
delivered by the Trustee to the Company which have been redeemed either at the
election of the Company pursuant to the terms of such Securities or through the
application of permitted optional sinking fund payments pursuant to the terms of
such Securities; provided that such Securities have not been previously so
credited. Such Securities shall be received and credited for such purpose by the
Trustee at the Redemption Price specified in such Securities for redemption
through operation of the sinking fund and the amount of such mandatory sinking
fund payment shall be reduced accordingly.

      Section 12.03. Redemption of Securities for Sinking Fund. Not less than 60
days prior to each sinking fund payment date for any series of Securities, the
Company will deliver to the Trustee a certificate signed by the Treasurer or any
Assistant Treasurer of the Company
<PAGE>   63
                                                                              56


specifying the amount of the next ensuing sinking fund payment for that series
pursuant to the terms of that series, the portion thereof, if any, which is to
be satisfied by payment of cash and the portion thereof, if any, which is to be
satisfied by delivering or crediting Securities of that series pursuant to
Section 12.02 (which Securities will, if not previously delivered, accompany
such certificate) and whether the Company intends to exercise its right to make
a permitted optional sinking fund payment with respect to such series. Such
certificate shall also state that no Event of Default has occurred and is
continuing with respect to such series. Such certificate shall be irrevocable
and upon its delivery the Company shall be obligated to make the cash payment or
payments therein referred to, if any, on or before the next succeeding sinking
fund payment date. In the case of the failure of the Company to deliver such
certificate (or to deliver the Securities specified in this paragraph), the
sinking fund payment due on the next succeeding sinking fund payment date for
that series shall be paid entirely in cash and shall be sufficient to redeem the
principal amount of such Securities subject to a mandatory sinking fund payment
without the option to deliver or credit Securities as provided in Section 12.02
and without the right to make any optional sinking fund payment, if any, with
respect to such series.

      Any sinking fund payment or payments (mandatory or optional) made in cash
plus any unused balance of any preceding sinking fund payments made in cash
which shall equal or exceed $100,000 (or a lesser sum if the Company shall so
request) with respect to the Securities of any particular series shall be
applied by the Trustee on the sinking fund payment date on which such payment is
made (or, if such payment is made before a sinking fund payment date, on the
sinking fund payment date following the date of such payment) to the redemption
of such Securities at the Redemption Price specified in such Securities for
operation of the sinking fund together with accrued interest to the date fixed
for redemption. Any sinking fund moneys not so applied or allocated by the
Trustee to the redemption of Securities shall be added to the next cash sinking
fund payment received by the Trustee for such series and, together with such
payment, shall be applied in accordance with the provisions of this Section
12.03. Any and all sinking fund moneys with respect to the Securities of any
particular series held by the Trustee on the last sinking fund payment date with
respect to Securities of such series and not held for the payment or redemption
of particular Securities shall be applied by the Trustee, together with other
moneys, if necessary, to be deposited sufficient for the purpose, to the payment
of the principal of the Securities of that series at maturity.

      The Trustee shall select the Securities to be redeemed upon such sinking
fund payment date in the manner specified in the last paragraph of Section 11.02
and the Company shall cause notice of the redemption thereof to be given in the
manner provided in Section 11.02 except that the notice of redemption shall also
state that the Securities are being redeemed by operation of the sinking fund.
Such notice having been duly given, the redemption of such Securities shall be
made upon the terms and in the manner stated in Section 11.03.

      On or before each sinking fund payment date, the Company shall pay to the
Trustee in cash a sum equal to any interest accrued to the date fixed for
redemption of Securities or portions thereof to be redeemed on such sinking fund
payment date pursuant to this Section.

      The Trustee shall not redeem any Securities of a series with sinking fund
moneys or mail any notice of redemption of such Securities by operation of the
sinking fund for such series during the continuance of a default in payment of
interest on such Securities or of any Event of
<PAGE>   64
                                                                              57


Default (other than an Event of Default occurring as a consequence of this
paragraph) with respect to such Securities, except that if the notice of
redemption of any such Securities shall theretofore have been mailed in
accordance with the provisions hereof, the Trustee shall redeem such Securities
if cash sufficient for that purpose shall be deposited with the Trustee for that
purpose in accordance with the terms of this Article. Except as aforesaid, any
moneys in the sinking fund for such series at the time when any such default or
Event of Default shall occur and any moneys thereafter paid into such sinking
fund shall, during the continuance of such default or Event of Default, be held
as security for the payment of such Securities; provided, however, that in case
such Event of Default or default shall have cured or waived as provided herein,
such moneys shall thereafter be applied on the next sinking fund payment date
for such Securities on which such moneys may be applied pursuant to the
provisions of this Section.

                                ARTICLE THIRTEEN

                                HOLDERS' MEETINGS

      Section 13.01. Purposes of Meetings. A meeting of Holders of Securities of
any or all series may be called at any time and from time to time pursuant to
the provisions of this Article for any one or more of the following purposes.

            (1) to give any notice to the Company or to the Trustee, or to give
      any directions to the Trustee, or to consent to the waiving of any default
      hereunder and its consequences, or to take any other action authorized to
      be taken by Holders pursuant to any of the provisions of Article Five;

            (2) to remove the Trustee and appoint a successor trustee pursuant
      to the provisions of Article Six;

            (3)   to consent to the execution of an indenture or indentures
      supplemental hereto pursuant to the provisions of Section 9.02; or

            (4) to take any other action authorized to be taken by or on behalf
      of the Holders of any specified aggregate principal amount of the
      Securities of any or all series, as the case may be, under any other
      provision of this Indenture or under applicable law.

      Section 13.02. Call of Meetings by Trustee. The Trustee may at any time
call a meeting of Holders of Securities of any or all series to take any action
specified in Section 13.01, to be held at such time and at such place in the
Borough of Manhattan, The City of New York, as the Trustee shall determine.
Notice of every meeting of the Holders of Securities of any or all series,
setting forth the time and the place of such meeting and in general terms the
action proposed to be taken at such meeting, shall be mailed not less than 20
nor more than 60 days prior to the date fixed for the meeting to Holders of
Securities of each series affected.

      Section 13.03.    Call of Meetings by Company or Holders.

      In case at any time the Company, pursuant to a Board Resolution, or the
Holders of not less than 10% in aggregate principal amount of the Outstanding
Securities of any or all series, as the case may be, shall have requested the
Trustee to call a meeting of Holders of Securities of all
<PAGE>   65
                                                                              58


series, if they hold not less than 10% of all Outstanding Securities, or a
meeting of Holders of Outstanding Securities of the series of which they hold
not less than 10%, to take any action authorized in Section 13.01, by written
request setting forth in reasonable detail the action proposed to be taken at
the meeting, and the Trustee shall not have mailed notice of such meeting within
20 days after receipt of such request, then the Company or the Holders in the
amount above specified may determine the time and the place for such meeting and
may call such meeting to take any action authorized in Section 13.01 by mailing
notice thereof as provided in Section 13.02.

      Section 13.04.    Qualifications for Voting.

      To be entitled to vote at any meeting of Holders, a Person shall be a
Holder at the close of business two Business Days prior to such meeting of one
or more Securities with respect to which such meeting is being held or be a
Person appointed by an instrument in writing as proxy by such a Holder. The only
Persons who will be entitled to be present or to speak at any meeting of Holders
shall be the Persons entitled to vote at such meeting and their counsel and any
representatives of the Trustee and its counsel and any representatives of the
Company and its counsel.

      Section 13.05.    Regulations.

      Notwithstanding any other provision of this Indenture, the Trustee may
make such reasonable regulations as it may deem advisable for any meeting of
Holders, in regard to the appointment of proxies, the appointment and duties of
inspectors of votes, the submission and examination of proxies, certificates and
other evidence of the right to vote, and such other matters concerning the
conduct of the meeting as it shall think fit. Except as otherwise permitted or
required by any such regulations, the holding of Securities shall be proved in
the manner specified in Section 1.04 and the appointment of any proxy shall be
proved in the manner specified in said Section 1.04; provided, however, that
such regulations may provide that written instruments appointing proxies,
regular on their face, may be presumed valid and genuine without the proof
hereinbefore or in said Section 1.04 specified.

      The Trustee shall, by an instrument in writing, appoint a temporary
chairman of the meeting, unless the meeting shall have been called by the
Company or the Holders as provided in Section 13.03, in which case the Company
or the Holders calling the meeting, as the case may be, shall in like manner
appoint a temporary chairman. A permanent chairman and a permanent secretary of
the meeting may be elected by vote of the Holders of a majority in principal
amount of the Securities with respect to which such meeting is being held
represented at the meeting and entitled to vote.

      At any meeting each Holder or proxy shall be entitled to one vote for each
$1,000 principal amount of Securities with respect to which such meeting is
being held or represented by him and Outstanding (in the case of Original Issue
Discount Securities, such principal amount to be determined as provided in the
definition of "Outstanding"); provided, however, that no vote shall be cast or
counted at any meeting in respect of any Security challenged as not Outstanding
and ruled by the chairman of the meeting to be not Outstanding. The chairman of
the meeting shall have no right to vote other than by virtue of Securities held
by him or instruments in writing
<PAGE>   66
                                       59


as aforesaid duly designating him as the Person to vote on behalf of other
Holders. Any meeting of Holders duly called pursuant to the provisions of
Section 13.02 or 13.03 may be adjourned from time to time by vote of the Holders
(or proxies for such Holders) of a majority of the Securities with respect to
which such meeting is being held represented at the meeting, and entitled to
vote, and the meeting may be held as so adjourned without further notice.

      Notwithstanding anything in this Section to the contrary, at any meeting
of Holders, the presence of Persons holding or representing Securities with
respect to which such meeting is being held in an aggregate principal amount
sufficient under the appropriate provision of this Indenture to take action on
any business for the transaction of which such meeting was called shall
constitute a quorum, but, if less than a quorum is present, the Persons holding
or representing a majority in aggregate principal amount of such Securities
represented at the meeting may adjourn such meeting with the same effect, for
all intents and purposes, as though a quorum had been present.

      Section 13.06.    Voting.

      The vote upon any resolution submitted to any meeting of Holders of
Securities with respect to which such meeting is being held shall be by written
ballots on which shall be subscribed the signature of such Holders or proxies
and the serial number or numbers and the principal amounts of the Securities
held or represented by them. The chairman of the meeting shall appoint two
inspectors of votes who shall count all votes cast at the meeting for or against
any resolution and who shall make and file with the secretary of the meeting
their verified written reports in duplicate of all votes cast at the meeting. A
record in duplicate of the proceedings of each meeting of Holders shall be
prepared by the secretary of the meeting and there shall be attached to said
record the original reports of the inspectors of votes on any vote by ballot
taken thereat and affidavits by one or more Persons having knowledge of the
facts setting forth a copy of the notice of the meeting and showing that said
notice was mailed as provided in Section 13.02. The record shall be signed and
verified by the affidavits of the chairman and secretary of the meeting and one
of the duplicates shall be delivered to the Company and the other to the Trustee
to be preserved by the Trustee, the latter to have attached thereto the ballots
voted at the meeting.

      Any record so signed and verified shall be conclusive evidence of the
matters therein stated.

      Section 13.07.    Revocation by Holders.

      At any time prior to (but not after) the evidencing to the Trustee, in the
manner provided in Section 1.04, of the taking of any action by the Holders of
the percentage in aggregate principal amount of the Securities specified in this
Indenture in connection with such action, any Person who is the Holder of a
Security the serial number of which is included in the Securities, the Holders
of which have consented to such action may, by filing written notice with the
Trustee at the Corporate Trust Office and upon proof of holding as provided in
Section 1.04, revoke such consent so far as concerns such Security, or if such
Security is a Predecessor Security, so far as concerns the portion of such
Security of which such Persons is the Holder. Except as aforesaid any such
consent given by the Holder of any Security shall be conclusive and
<PAGE>   67
                                                                              60


binding upon such Holder and upon all future Holders and owners of such Security
and of any Security issued in exchange therefor or in lieu thereof, irrespective
of whether or not any notation in regard thereto is made upon such Security. Any
action taken by the Holders of the percentage in aggregate principal amount of
the Securities specified in this Indenture in connection with such action shall
be conclusively binding upon the Company, the Trustee and the Holders of all the
Securities.

      Section 13.08.    No Delay.

      Nothing in this Article contained shall be deemed or construed to require
any delay in the exercise of any right or rights conferred upon or reserved to
the Trustee or to the Holders under any of the provisions of this Indenture or
of the Securities by reason of any call of a meeting of Holders or any rights
expressly or impliedly conferred hereunder to make such call.

      Section 13.09. Action by Holders. Whenever in this Indenture it is
provided that the Holders of a specified percentage in aggregate principal
amount of the Securities of any or all series may take any action (including the
making of any demand or request, the giving of any notice, consent or waiver or
the taking of any other action) the fact that at the time of taking any such
action the Holders of such specified percentage have joined therein may be
evidenced (a) by any instrument or any number of instruments of similar tenor
executed by such Holders in person or by agent or proxy appointed in writing, or
(b) by the record of such Holders voting in favor thereof at any meeting of such
Holders duly called and held in accordance with the provisions of this Article
Thirteen, or (c) by a combination of such instrument or instruments and any such
record of such a meeting of such Holders.

                                ARTICLE FOURTEEN

                                   DEFEASANCE

      Section 14.01. Applicability of Article. The provisions of this Article
shall be applicable to Securities of a Series except as otherwise specified
pursuant to Section 3.01 for Securities of such series.

      Section 14.02. Defeasance Upon Deposit of Moneys or U.S. Government
Obligations. At the Company's option, either (a) the Company shall be deemed to
have been Discharged (as defined below) from its obligations with respect to
Securities of any series ("Legal Defeasance Option") or (b) the Company shall
cease to be under any obligation to comply with any term, provision or condition
set forth in Sections 8.01, 8.03, 10.04, 10.05, 10.08 and 10.09 with respect to
Securities of any series (and, if so specified pursuant to Section 3.01, any
other obligation of the Company or restrictive covenant added for the benefit of
such series pursuant to Section 3.01) ("Covenant Defeasance Option") at any time
after the applicable conditions set forth below have been satisfied:

            (1) the Company shall have deposited or caused to be deposited
      irrevocably with the Trustee as trust funds in trust, specifically pledged
      as security for, and dedicated solely to, the benefit of the Holders of
      the Securities of such series (i) money in an
<PAGE>   68
                                       61


      amount, or (ii) U.S. Government Obligations (as defined below) which
      through the payment of interest and principal in respect thereof in
      accordance with their terms will provide, not later than one day before
      the due date of any payment, money in an amount, or (iii) a combination of
      (i) and (ii), sufficient, in the opinion (with respect to (i) and (ii)) of
      a nationally recognized firm of independent public accountants expressed
      in a written certification thereof delivered to the Trustee, to pay and
      discharge each installment of principal (including any mandatory sinking
      fund payments) of and premium, if any, and interest on, the Outstanding
      Securities of such series on the dates such installments of interest or
      principal and premium are due;

            (2) such deposit shall not cause the Trustee with respect to the
      Securities of that series to have a conflicting interest as defined in
      Section 6.08 and for purposes of the Trust Indenture Act with respect to
      the Securities of any series;

            (3) such deposit will not result in a breach or violation of, or
      constitute a default under, this Indenture or any other agreement or
      instrument to which the Company is a party or by which it is bound;

            (4) no Event of Default or event (including such deposit) which,
      with notice or lapse of time or both, would become an Event of Default
      with respect to the Securities of such series shall have occurred and be
      continuing on the date of such deposit and, with respect to the legal
      defeasance option only, no Event of Default under Section 5.01(e) or
      Section 5.01(f) or event which with the giving of notice or lapse of time,
      or both, would become an Event of Default under Section 5.01(e) or Section
      5.01(f) shall have occurred and be continuing on the 91st day after such
      date; and

            (5) the Company shall have delivered to the Trustee an Opinion of
      Counsel or a ruling from the Internal Revenue Service to the effect that
      the Holders of the Securities of such series will not recognize income,
      gain or loss for Federal income tax purposes as a result of such deposit,
      defeasance or Discharge.

      Notwithstanding the foregoing, if the Company exercises its covenant
defeasance option and an Event of Default under Section 5.01(e) or Section
5.01(f) or event which with the giving of notice or lapse of time, or both,
would become an Event of Default under Section 5.01(e) or Section 5.01(f) shall
have occurred and be continuing on the 91st day after the date of such deposit,
the obligations of the Company referred to under the definition of covenant
defeasance option with respect to such Securities shall be reinstated.

      "Discharged" means that the Company shall be deemed to have paid and
discharged the entire indebtedness represented by, and obligations under, the
Securities of such series and to have satisfied all the obligations under this
Indenture relating to the Securities of such series (and the Trustee, at the
expense of the Company, shall execute proper instruments acknowledging the
same), except (A) the rights of Holders of Securities of such series to receive,
from the trust fund described in clause (1) above, payment of the principal of
(and premium, if any) and interest on such Securities when such payments are
due, (B) the Company's obligations with respect to the Securities of such series
under Sections 3.05, 3.06, 3.07, 10.02 and 14.03 and to the Trustee
<PAGE>   69
                                                                              62


under Section 6.07 and (C) the rights, powers, trusts, duties and immunities of
the Trustee hereunder.

      "U.S. Government Obligations" means securities that are (i) direct
obligations of the United States for the payment of which its full faith and
credit is pledged, or (ii) obligations of a Person controlled or supervised by
and acting as an agency or instrumentality of the United States the payment of
which is unconditionally guaranteed as a full faith and credit obligation by the
United States, which, in either case under clauses (i) or (ii), are not callable
or redeemable at the option of the issuer thereof, and shall also include a
depository receipt issued by a bank or trust company as custodian with respect
to any such U.S. Government Obligation or a specific payment of interest on or
principal of any such U.S. Government obligation held by such custodian for the
account of the holder of a depository 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 depository receipt from any amount received by the
custodian in respect of the U.S. Government Obligation or the specific payment
of interest on or principal of the U.S. Government Obligation evidenced by such
depository receipt.

      Section 14.03. Deposited Moneys and U.S. Government Obligations to Be Held
in Trust. All moneys and U.S. Government Obligations deposited with the Trustee
pursuant to Section 14.02 in respect of Securities of a series shall be held in
trust and applied by it, in accordance with the provisions of such Securities
and this Indenture, to the payment, either directly or through any Paying Agent
(including the Company acting as its own Paying Agent) as the Trustee may
determine, to the Holders of such Securities, of all sums due and to become due
thereon for principal (and premium, if any) and interest, if any, but such money
need not be segregated from other funds except to the extent required by law.

      Section 14.04. Repayment to Company. The Trustee and any Paying Agent
shall promptly pay or return to the Company upon Company Request any moneys or
U.S. Government Obligations held by them at any time that are not required for
the payment of the principal of (and premium, if any) and interest on the
Securities of any series for which money or U.S. Government Obligations have
been deposited pursuant to Section 14.02.

      The provisions of the last paragraph of Section 10.03 shall apply to any
money held by the Trustee or any Paying Agent under this Article that remains
unclaimed for two years after the Maturity of any series of Securities for which
money or U.S. Government Obligations have been deposited pursuant to Section
14.02.

                                 ARTICLE FIFTEEN

                                   GUARANTEES

      Section 15.01. Guarantees. Each Guarantor of a particular series of
Securities hereby unconditionally guarantees (each such guarantee to be referred
to herein as a "Guarantee"), jointly and severally with each other Guarantor of
the Securities of that series, if any, to each Holder of such Securities
authenticated and delivered by the Trustee and to the Trustee and its successors
and assigns, irrespective of the validity and enforceability of this Indenture,
such Securities or the obligations of the Company hereunder or thereunder, (i)
the due and punctual
<PAGE>   70
                                                                              63


payment of the principal of and any premium or interest on such Securities,
whether at maturity or on an interest payment date, by acceleration, pursuant to
an offer to purchase such Securities or otherwise, and interest on the overdue
principal of and interest, if any, on such Securities, if lawful, and all other
obligations of the Company to the Holders of such Securities or the Trustee
hereunder or thereunder shall be promptly paid in full, all in accordance with
the terms hereof and thereof including all amounts payable to the Trustee under
Section 6.07 hereof, and (ii) in case of any extension of time of payment or
renewal of any such Securities or any of such other obligations, the same shall
be promptly paid in full when due or to be performed in accordance with the
terms of the extension or renewal, whether at stated maturity, by acceleration
or otherwise.

      If the Company fails to make any payment when due of any amount so
guaranteed for whatever reason, each Guarantor of the Securities of that series
shall be obligated, jointly and severally with each other such Guarantor, if
any, to pay the same immediately. Each Guarantor hereby agrees that its
obligations hereunder shall be continuing, absolute and unconditional,
irrespective of, and shall be unaffected by, the validity, regularity or
enforceability of the Securities, this Indenture, the absence of any action to
enforce the same, any waiver or consent by any Holder of the Securities or the
Trustee with respect to any provisions hereof or thereof, the recovery of any
judgment against the Company, any action to enforce the same or any other
circumstance which might otherwise constitute a legal or equitable discharge or
defense of such Guarantor. Each Guarantor hereby waives diligence, presentment,
demand of payment, demand of performance, filing of claims with a court in the
event of insolvency or bankruptcy of the Company, any right to require a
proceeding first against the Company, the benefit of discussion, protest, notice
and all demand whatsoever and covenants that its Guarantee shall not be
discharged except by complete performance of the obligations contained in the
Securities guaranteed by such Guarantee, in this Indenture and in this Article
Fifteen. If any Holder of Securities of a series guaranteed hereby or the
Trustee is required by any court or otherwise to return to the Company or any
Guarantor of such Securities, or any custodian, trustee, liquidator or other
similar official acting in relation to the Company or any Guarantor of such
Securities, any amount paid by the Company or any Guarantor of such Securities
to the Trustee or such Holder, this Article Fifteen, to the extent theretofore
discharged with respect to any Guarantee of such Securities, shall be reinstated
in full force and effect. Each Guarantor agrees that it shall not be entitled to
any right of subrogation in relation to the Holders of Securities of a series
guaranteed hereby by such Guarantor in respect of any obligations guaranteed
hereby by such Guarantee until payment in full of all such obligations. Each
Guarantor further agrees that, as between such Guarantor, on the one hand, and
the Holders of Securities of a series guaranteed hereby by such Guarantor and
the Trustee on the other hand, (i) the maturity of the obligations guaranteed
hereby by such Guarantee may be accelerated as provided in Article Five hereof
for the purposes of such Guarantee, notwithstanding any stay, injunction or
other prohibition preventing such acceleration in respect of the obligations
guaranteed hereby and (ii) in the event of any 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 such Guarantor, jointly and
severally with any other Guarantor of such Securities, for the purpose of this
Article Fifteen. In addition, without limiting the foregoing, upon the
effectiveness of an acceleration under Article Five, the Trustee may make a
demand for payment on the Securities under any Guarantee thereof not discharged.
<PAGE>   71
                                                                              64


      With respect to each Guarantee by a Guarantor, such Guarantor shall be
subrogated to all rights of the Holder of any Securities guaranteed hereby by
such Guarantee against the Company in respect of any amounts paid to such Holder
by such Guarantor pursuant to the provisions of such Guarantee; provided that
such Guarantor shall not be entitled to enforce, or to receive any payments
arising out of or based upon, such right of subrogation until the principal of
and interest on all such Securities shall have been paid in full.

      The Guarantees provided in this Section 15.01 shall not be valid or become
obligatory for any purpose with respect to a Security until the certificate of
authentication on such Security shall have been signed by the Trustee or any
duly appointed agent.

      Section 15.02. Obligations of the Guarantor Unconditional. Nothing
contained in this Article Fifteen or elsewhere in this Indenture or in any
Security is intended to or shall impair, as between a Guarantor and the Holders
of the Securities guaranteed by such Guarantor's Guarantee, the obligations of
such Guarantor, which are absolute and unconditional, to pay to such Holders the
principal of and interest on such Securities as and when the same shall become
due and payable in accordance with the provisions of such Guarantee or is
intended to or shall affect the relative rights of such Holders and creditors of
such Guarantor, nor shall anything herein or therein prevent the Trustee or any
such Holder from exercising all remedies otherwise permitted by applicable law
upon Default under this Indenture in respect of cash, property or securities of
such Guarantor received upon the exercise of any such remedy;

      Upon any distribution of assets of a Guarantor referred to in this Article
Fifteen, the Trustee, subject to the provisions of Sections 6.01 and 6.03, and
the Holders of the Securities guaranteed hereby by such Guarantor shall be
entitled to rely upon any order or decree made by any court of competent
jurisdiction in which such dissolution, winding up, liquidation or
reorganization proceedings are pending, or a certificate of the liquidating
trustee or agent or other person making any distribution to the Trustee or to
such Holders, for the purpose of ascertaining the persons entitled to
participate in such distribution, the holders of other indebtedness of such
Guarantor, the amount thereof or payable thereon, the amount or amounts paid or
distributed thereon and all other facts pertinent thereto or to this Article
Fifteen.

      Section 15.03. Article Fifteen Not To Prevent Events of Default. The
payment of principal or interest on the Securities of any series by reason of
any provision in this Article Fifteen shall not be construed as preventing the
occurrence of an Event of Default.

      Section 15.04. Execution and Delivery of Guarantee. To evidence a
Guarantee, the Guarantor shall endorse a Guarantee Notation, substantially in
the form of Exhibit A hereto, on each Security authenticated and delivered by
the Trustee that is guaranteed by such Guarantee and this Indenture shall be
executed on behalf of such Guarantor by its Chairman of the Board, its President
or one of its Vice Presidents under a facsimile of its seal reproduced thereon.

      Each Guarantor hereby agrees that its Guarantee shall remain in full force
and effect notwithstanding any failure to endorse the Guarantee Notation on each
such Security.
<PAGE>   72
                                                                              65


      If an officer whose signature is on this Indenture or on the Securities
guaranteed hereby no longer holds that office at the time the Trustee
authenticates the Security on which a notation of a Guarantee is endorsed, such
Guarantee shall be valid nevertheless.

      The delivery of any Security by the Trustee, after the authentication
thereof hereunder, shall constitute due delivery of each Guarantee thereof.

                                   * * * * * *

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

      IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be
duly executed, and their respective corporate seals to be hereunto affixed and
attested, all as of the day and year first above written.

                                     KERR-MCGEE CORPORATION

                                     By
                                       ----------------------------------------
                                                           Chairman of the Board

[CORPORATE SEAL]

Attest:

--------------------------------
                        Secretary

[CORPORATE SEAL]
                                     CITIBANK, N.A.

                                     By
                                       ----------------------------------------

Attest:

--------------------------------
<PAGE>   73
STATE OF OKLAHOMA       )
                        ) ss.:
                        )
COUNTY OF OKLAHOMA      )

       On the        day of            , 2001, before me personally came      ,
to me known, who, being by me duly sworn, did depose and say that he is Chairman
of the Board of KERR-MCGEE CORPORATION, one of the corporations described in and
which executed the foregoing instrument; that he knows the seal of said
corporation; that the seal affixed to said instrument is such corporate seal;
that is was so affixed by authority of the Board of Directors of said
corporation, and that he signed his name thereto by like authority.

                                         --------------------------------------
                                                      Notary Public

[NOTARIAL SEAL]

My Commission Expires

STATE OF NEW YORK        )
                         ) ss.:
                         )
COUNTY OF NEW YORK       )

On the       day of             , 2001, before me personally came       , to me
known, who, being by me duly sworn, did depose and say that he is a
of CITIBANK, N.A., one of the corporations described in and which executed the
foregoing instrument; that he knows the seal of said corporation; that the seal
affixed to said instrument is such corporate seal; that it was so affixed by
authority of the Board of Directors of said corporation, and that he signed his
name thereto by like authority.

[NOTARIAL SEAL]
                                         --------------------------------------
                                                      Notary Public
<PAGE>   74
                                                                       EXHIBIT A

                          [FORM OF NOTATION OF SECURITY
                             RELATING TO GUARANTEE]

                                    GUARANTEE

      [Kerr - McGee Operating Corporation/HS Resources, Inc.] (hereinafter
referred to as the "Guarantor", which term includes any successor person under
the Indenture (the "Indenture") referred to in the Security upon which this
notation is endorsed (the "Endorsed Security")) has unconditionally guaranteed
(i) the due and punctual payment of the principal of, premium, if any, and
interest on the Endorsed Security and all other Securities of the same series as
the Endorsed Security (the "Guaranteed Securities"), whether at maturity, by
acceleration or otherwise, the due and punctual payment of interest on the
overdue principal of, premium, if any, and interest, if any, on the Guaranteed
Securities, to the extent lawful, and the due and punctual performance of all
other obligations of the Company to the Holders of Guaranteed Securities or the
Trustee all in accordance with the terms set forth in Article Fifteen of the
Indenture and (ii) in case of any extension of time of payment or renewal of any
Guaranteed Securities or any of such other obligations, that the 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.
Capitalized terms not otherwise defined herein shall have the meanings ascribed
thereto in the Indenture.

      The obligations of the Guarantor to the Holders of Guaranteed Securities
and to the Trustee pursuant to the Guarantee evidenced hereby and the Indenture
are expressly set forth in Article Fifteen of the Indenture and reference is
hereby made to such Indenture for the terms of such Guarantee.

      No stockholder, officer, director or incorporator, as such, past, present
or future, of the Guarantor shall have any personal liability under the
Guarantee evidenced hereby by reason of his or its status as such stockholder,
officer, director or incorporator.

      The Guarantee evidenced hereby shall not be valid or obligatory for any
purpose until the certificate of authentication of the Guaranteed Securities
shall have been executed by the Trustee under the Indenture by the manual
signature of one of the Trustee's authorized officers.

                                    Guarantor

                                    [SEAL]

                                    [KERR - MCGEE OPERATING CORPORATION/ HS
                                    RESOURCES, INC.]

                                    By___________________________________

                                    By___________________________________