<PAGE>

                                                                     EXHIBIT 4.4

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                           FRONTIER ESCROW CORPORATION

                           TO BE MERGED WITH AND INTO

                            FRONTIER OIL CORPORATION

                          8.000% SENIOR NOTES DUE 2013,
                              SERIES A AND SERIES B

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                                    INDENTURE

                           DATED AS OF APRIL 17, 2003

                                   ----------

                             WELLS FARGO BANK, N.A.

                                     TRUSTEE

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                            CROSS-REFERENCE TABLE*

Trust Indenture
Act Section                                                  Indenture Section

310(a)(1).........................................................        7.10
     (a)(2).......................................................        7.10
     (a)(3).......................................................         N/A
     (a)(4).......................................................         N/A
     (a)(5).......................................................        7.10
     (b)..........................................................        7.10
     (c)..........................................................         N/A
311(a)............................................................        7.11
     (b)..........................................................        7.11
     (c)..........................................................         N/A
312(a)............................................................        2.05
     (b)..........................................................       12.03
     (c)..........................................................       12.03
313(a)............................................................        7.06
     (b)(1).......................................................        7.06
     (b)(2).......................................................  7.06, 7.07
     (c).......................................................... 7.06, 12.02
     (d)..........................................................        7.06
314(a)............................................................ 4.03, 12.05
     (b)..........................................................         N/A
     (c)(1).......................................................       12.04
     (c)(2).......................................................       12.04
     (c)(3).......................................................         N/A
     (d)..........................................................         N/A
     (e)..........................................................       12.05
     (f)..........................................................         N/A
315(a)............................................................        7.01
     (b).......................................................... 7.05, 12.02
     (c)..........................................................        7.01
     (d)..........................................................        7.01
     (e)..........................................................        6.11
316(a) (last sentence)............................................        2.09
     (a)(1)(A)....................................................        6.05
     (a)(1)(B)....................................................        6.04
     (a)(2).......................................................         N/A
     (b)..........................................................        6.07
     (c)..........................................................        2.12
317(a)(1).........................................................        6.08
     (a)(2).......................................................        6.09
     (b)..........................................................        2.04
318(a)............................................................       12.01
     (b)..........................................................         N/A
     (c)..........................................................       12.01

----------
N/A means not applicable.
*  This Cross-Reference Table is not part of the Indenture.

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                                TABLE OF CONTENTS

                                                                           PAGE
                                                                           ----

ARTICLE 1. DEFINITIONS AND INCORPORATION BY REFERENCE........ ............... 1

   Section 1.01   Definitions................................................ 1
   Section 1.02   Other Definitions..........................................17
   Section 1.03   Incorporation by Reference of Trust Indenture Act..........17
   Section 1.04   Rules of Construction......................................18

ARTICLE 2. THE NOTES.........................................................18

   Section 2.01   Form and Dating............................................18
   Section 2.02   Execution and Authentication...............................20
   Section 2.03   Registrar and Paying Agent.................................20
   Section 2.04   Paying Agent to Hold Money in Trust........................21
   Section 2.05   Holder Lists...............................................21
   Section 2.06   Transfer and Exchange......................................21
   Section 2.07   Replacement Notes..........................................32
   Section 2.08   Outstanding Notes..........................................33
   Section 2.09   Treasury Notes.............................................33
   Section 2.10   Temporary Notes............................................33
   Section 2.11   Cancellation...............................................34
   Section 2.12   Defaulted Interest.........................................34

ARTICLE 3. REDEMPTION AND PREPAYMENT.........................................34

   Section 3.01   Notices to Trustee.........................................34
   Section 3.02   Selection of Notes to Be Redeemed or Purchased.............34
   Section 3.03   Notice of Redemption.......................................35
   Section 3.04   Effect of Notice of Redemption.............................36
   Section 3.05   Deposit of Redemption or Purchase Price....................36
   Section 3.06   Notes Redeemed or Purchased in Part........................36
   Section 3.07   Optional Redemption........................................36
   Section 3.08   Special Mandatory Redemption...............................37
   Section 3.09   Offer to Purchase by Application of Excess Proceeds........37

ARTICLE 4. COVENANTS.........................................................39

   Section 4.01   Payment of Notes...........................................39
   Section 4.02   Maintenance of Office or Agency............................40
   Section 4.03   Reports....................................................40
   Section 4.04   Compliance Certificate.....................................41
   Section 4.05   Taxes......................................................41
   Section 4.06   Stay, Extension and Usury Laws.............................41
   Section 4.07   Restricted Payments........................................42
   Section 4.08   Dividend and Other Payment Restrictions Affecting
                    Subsidiaries.............................................44
   Section 4.09   Incurrence of Indebtedness and Issuance of
                    Disqualified Stock.......................................45
   Section 4.10   Asset Sales................................................45

                                        i

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   Section 4.11   Transactions with Affiliates...............................46
   Section 4.12   Liens......................................................47
   Section 4.13   Guarantees.................................................47
   Section 4.14   Corporate Existence........................................47
   Section 4.15   Offer to Repurchase Upon Change of Control.................48
   Section 4.16   Sale-and-Leaseback Transactions............................49
   Section 4.17   No Inducements.............................................49
   Section 4.18   Line of Business...........................................49
   Section 4.19   Limitations on Frontier Escrow Corporation.................49
   Section 4.20   Changes in Covenants when Notes Rated Investment Grade.....50

ARTICLE 5. SUCCESSORS........................................................50

   Section 5.01   Merger, Consolidation, or Sale of Assets...................50
   Section 5.02   Successor Corporation Substituted..........................51

ARTICLE 6. DEFAULTS AND REMEDIES.............................................51

   Section 6.01   Events of Default..........................................51
   Section 6.02   Acceleration...............................................53
   Section 6.03   Other Remedies.............................................54
   Section 6.04   Waiver of Past Defaults....................................54
   Section 6.05   Control by Majority........................................54
   Section 6.06   Limitation on Suits........................................54
   Section 6.07   Rights of Holders of Notes to Receive Payment..............55
   Section 6.08   Collection Suit by Trustee.................................55
   Section 6.09   Trustee May File Proofs of Claim...........................55
   Section 6.10   Priorities.................................................55
   Section 6.11   Undertaking for Costs......................................56

ARTICLE 7. TRUSTEE...........................................................56

   Section 7.01   Duties of Trustee..........................................56
   Section 7.02   Rights of Trustee..........................................57
   Section 7.03   Individual Rights of Trustee...............................58
   Section 7.04   Trustee's Disclaimer.......................................58
   Section 7.05   Notice of Defaults.........................................58
   Section 7.06   Reports by Trustee to Holders of the Notes.................58
   Section 7.07   Compensation and Indemnity.................................58
   Section 7.08   Replacement of Trustee.....................................59
   Section 7.09   Successor Trustee by Merger, etc...........................60
   Section 7.10   Eligibility; Disqualification..............................60
   Section 7.11   Preferential Collection of Claims Against Company..........60

ARTICLE 8. LEGAL DEFEASANCE AND COVENANT DEFEASANCE..........................61

   Section 8.01   Option to Effect Legal Defeasance or Covenant Defeasance...61
   Section 8.02   Legal Defeasance and Discharge.............................61
   Section 8.03   Covenant Defeasance........................................61
   Section 8.04   Conditions to Legal or Covenant Defeasance.................62

                                       ii

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   Section 8.05   Deposited Money and Government Securities to be
                    Held in Trust; Other Miscellaneous Provisions............63
   Section 8.06   Repayment to Company.......................................63
   Section 8.07   Reinstatement..............................................63

ARTICLE 9. AMENDMENT, SUPPLEMENT AND WAIVER..................................64

   Section 9.01   Without Consent of Holders of Notes........................64
   Section 9.02   With Consent of Holders of Notes...........................65
   Section 9.03   Compliance with Trust Indenture Act........................66
   Section 9.04   Revocation and Effect of Consents..........................66
   Section 9.05   Notation on or Exchange of Notes...........................66
   Section 9.06   Trustee to Sign Amendments, etc............................66

ARTICLE 10. GUARANTEES OF NOTES..............................................67

   Section 10.01  Guarantees.................................................67
   Section 10.02  Execution and Delivery of Guarantee........................68
   Section 10.03  Guarantors May Consolidate, etc., on Certain Terms.........68
   Section 10.04  Releases Following Sale of Assets..........................69
   Section 10.05  Releases Following Designation as an Unrestricted
                    Subsidiary...............................................69
   Section 10.06  Limitation on Guarantor Liability..........................69
   Section 10.07  "Trustee" to Include Paying Agent..........................70

ARTICLE 11. SATISFACTION AND DISCHARGE.......................................70

   Section 11.01  Satisfaction and Discharge.................................70
   Section 11.02  Application of Trust Money.................................71

ARTICLE 12. MISCELLANEOUS....................................................71

   Section 12.01  Trust Indenture Act Controls...............................71
   Section 12.02  Notices. 71
   Section 12.03  Communication by Holders of Notes with Other Holders
                    of Notes.................................................73
   Section 12.04  Certificate and Opinion as to Conditions Precedent.........73
   Section 12.05  Statements Required in Certificate or Opinion..............74
   Section 12.06  Rules by Trustee and Agents................................74
   Section 12.07  No Personal Liability of Directors, Officers, Employees
                    and Stockholders.........................................74
   Section 12.08  Governing Law..............................................74
   Section 12.09  No Adverse Interpretation of Other Agreements..............74
   Section 12.10  Successors.................................................74
   Section 12.11  Severability...............................................75
   Section 12.12  Counterpart Originals......................................75
   Section 12.13  Table of Contents, Headings, etc...........................75

                                       iii

<PAGE>

                                    EXHIBITS

EXHIBIT A-1       FORM OF NOTE.............................................A-1-1
EXHIBIT A-2       FORM OF REGULATION S TEMPORARY GLOBAL NOTE...............A-2-1
EXHIBIT B         FORM OF CERTIFICATE OF TRANSFER..........................  B-1
EXHIBIT C         FORM OF CERTIFICATE OF EXCHANGE..........................  C-1
EXHIBIT D         CERTIFICATE OF INSTITUTIONAL ACCREDITED INVESTOR.........  D-1
EXHIBIT E         FORM OF GUARANTEE........................................  E-1
EXHIBIT F         FORM OF SUPPLEMENTAL INDENTURE...........................  F-1
EXHIBIT G         FORM OF ASSUMPTION AGREEMENT ............................  G-1

                                       iv

<PAGE>

        This Indenture, dated as of April 17, 2003 is between Frontier Escrow
Corporation, a Delaware corporation and a wholly-owned subsidiary of Frontier
Oil Company, and Wells Fargo Bank, N.A., as trustee (the "Trustee").

        Unless specifically indicated otherwise, the term "Company" means the
entity known as Frontier Escrow Corporation on the date hereof or the entity
known as Frontier Oil Corporation on the date hereof, as applicable, together
with its successors in accordance with the terms of this Indenture, it being
understood that for purposes of Articles 4, 5 and 6, such term means Frontier
Oil Corporation. Frontier Escrow Corporation is expected to merge with and into
Frontier Oil Corporation with Frontier Oil Corporation as the surviving entity
pursuant to the Agreement of Merger, dated as of April 17, 2003, between
Frontier Escrow Corporation and Frontier Oil Corporation (the "Escrow Corp.
Merger") immediately prior to the mergers contemplated by the Agreement and Plan
of Merger, dated as of March 30, 2003, among Frontier Oil Corporation, Holly
Corporation, Front Range Himalaya Corporation (to be renamed Frontier Oil
Corporation following the consummation of the Merger, the "Parent"), Front Range
Merger Corporation and Himalaya Merger Corporation, pursuant to which (i) Front
Range Merger Corporation will merge with and into Frontier Oil Corporation with
Frontier Oil Corporation as the surviving corporation (the "Frontier Merger"),
(ii) Himalaya Merger Corporation will merge with and into Holly Corporation with
Holly Corporation as the surviving corporation (the "Holly Merger") and (iii)
upon consummation of the Frontier Merger and the Holly Merger, each of Frontier
Oil Corporation and Holly Corporation will become a wholly-owned subsidiary of
Front Range Himalaya Corporation and Front Range Himalaya Corporation will be
renamed Frontier Oil Corporation, and immediately thereafter Parent will
contribute the stock of Holly Corporation to the entity known as Frontier Oil
Corporation on the date hereof (together with the events described in clauses
(i) through (iii), the "Merger"). Immediately following the consummation of the
Escrow Corp. Merger, the entity known as Frontier Oil Corporation on the date
hereof will assume all of the obligations of Frontier Escrow Corporation under
this Indenture and the Notes (as defined).

        The Company and the Trustee agree as follows for the benefit of each
other and for the equal and ratable benefit of the Holders of the 8.00% Senior
Notes due 2013, Series A (the "Series A Notes"), whether issued on the date
hereof or from time to time thereafter, and the Holders of any 8.00% Senior
Notes due 2013, Series B (the "Series B Notes" and, together with the Series A
Notes, the "Notes") that may be issued in exchange for Series A Notes of equal
principal amount, without preference of one series of Notes over the other:

                                   ARTICLE 1.
                          DEFINITIONS AND INCORPORATION
                                  BY REFERENCE

Section 1.01    Definitions.

        "144A Global Note" means a permanent global senior note that contains
the paragraph referred to in footnote 1 and the additional schedule referred to
in footnote 4 to the form of the Note attached hereto as Exhibit A-1, and that
is deposited with the Note Custodian and registered in the name of the
Depository or its nominee, representing a series of Notes sold in reliance on
Rule 144A or another exemption from the registration requirements of the
Securities Act, other than Regulation S.

        "Adjusted Net Assets" of a Guarantor at any date shall mean the amount
by which the fair value of the properties and assets of such Guarantor exceeds
the total amount of liabilities, including, without limitation, contingent
liabilities (after giving effect to all other fixed and contingent liabilities
incurred or assumed on such date), but excluding liabilities under its
Guarantee, of such Guarantor at such date.

<PAGE>

        "Affiliate" of any specified Person means an "affiliate" of such Person,
as such term is defined for purposes of Rule 144 under the Securities Act.

        "Agent" means any Registrar, Paying Agent or co-registrar.

        "Applicable Procedures" means, with respect to any transfer or exchange
of beneficial interests in a Global Note, the rules and procedures of the
Depository that apply to such transfer and exchange.

        "Asset Sale" means (a) the sale, lease, conveyance or other disposition
(a "disposition") of any assets or rights (including, without limitation, by way
of a sale and leaseback), excluding dispositions in the ordinary course of
business (provided that the disposition of all or substantially all of the
assets of Parent or the Company and its Subsidiaries taken as a whole will be
governed by Sections 4.15 and/or 5.01 of this Indenture and not by the
provisions of Section 4.10 hereof), (b) the issue or sale by the Company or any
of its Restricted Subsidiaries of Equity Interests of any of the Company's
Subsidiaries, and (c) any Event of Loss, whether in the case of clause (a), (b)
or (c), in a single transaction or a series of related transactions, provided
that such transaction or series of transactions (i) has a fair market value in
excess of $1.0 million or (ii) results in the payment of net proceeds in excess
of $1.0 million. Notwithstanding the foregoing, the following transactions will
be deemed not to be Asset Sales: (A) a disposition of obsolete or excess
equipment or other assets; (B) a disposition of assets by the Company to a
Restricted Subsidiary or by a Restricted Subsidiary to the Company or to another
Restricted Subsidiary; (C) a disposition of Equity Interests by a Restricted
Subsidiary to the Company or to another Restricted Subsidiary; (D) a Permitted
Investment or Restricted Payment that is permitted by this Indenture; (E) any
lease of any equipment or other assets entered into in the ordinary course of
business and with respect to which the Company or any Restricted Subsidiary
thereof is the lessor, except any such lease that provides for the acquisition
of such assets by the lessee during or at the end of the term thereof for an
amount that is less than the fair market value thereof at the time the right to
acquire such assets occurs; (F) any sale of inventory or hydrocarbons or other
products (including crude oil and refined products), in each case in the
ordinary course of business of the Company's operations; (G) the sale or other
disposition of cash or Cash Equivalents; and (H) any trade or exchange by the
Company or any Restricted Subsidiary of any inventory or hydrocarbons or other
products (including crude oil and refined products) for similar products owned
or held by another Person, provided that the fair market value of the properties
traded or exchanged by the Company or such Restricted Subsidiary is reasonably
equivalent to the fair market value of the properties to be received by the
Company or such Restricted Subsidiary. The fair market value of any non-cash
proceeds of a disposition of assets and of any assets referred to in the
foregoing clause (H) of this definition shall be determined in the manner
contemplated in the definition of the term "fair market value," and, in the
event the fair market value so determined exceeds $2.0 million, the results of
such determination shall be set forth in an Officers' Certificate delivered to
the Trustee.

        "Attributable Indebtedness" in respect of a sale-and-leaseback
transaction means, at the time of determination, the present value (discounted
at the rate of interest implicit in such transaction, determined in accordance
with GAAP) of the obligation of the lessee for net rental payments during the
remaining term of the lease included in such sale-and-lease-back transaction
(including any period for which such lease has been extended or may, at the
option of the lessor, be extended). As used in the preceding sentence, the "net
rental payments" under any lease for any such period shall mean the sum of
rental and other payments required to be paid with respect to such period by the
lessee thereunder, excluding any amounts required to be paid by such lessee on
account of maintenance and repairs, insurance, taxes, assessments, water rates
or similar charges. In the case of any lease that is terminable by the lessee
upon payment of penalty, such net rental payment shall also include the amount
of such penalty, but no rent shall be considered as required to be paid under
such lease subsequent to the first date upon which it may be so terminated.

                                        2

<PAGE>

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

        "Board of Directors" means the board of directors of the Company or
Parent, as the case may be, or any committee thereof that is authorized to act
on behalf of such board.

        "Broker-Dealer" has the meaning set forth in the Registration Rights
Agreement.

        "Business Day" means any day other than a Legal Holiday.

        "Capital Lease Obligation" means, at the time any determination thereof
is to be made, the amount of the liability in respect of a capital lease that
would at such time be required to be capitalized on a balance sheet in
accordance with GAAP.

        "Capital Stock" means (a) in the case of a corporation, corporate stock,
(b) in the case of an association or business entity, any and all shares,
interests, participations, rights or other equivalents (however designated) of
corporate stock, (c) in the case of a partnership or limited liability company,
partnership or membership interests (whether general or limited) and (d) any
other interest or participation that confers on a Person the right to receive a
share of the profits and losses of, or distributions of assets of, the issuing
Person.

        "Cash Equivalents" means (a) United States dollars or up to $2.0 million
of Canadian dollars, (b) securities issued or directly and fully guaranteed or
insured by the United States government or any agency or instrumentality thereof
having maturities of not more than six months from the date of acquisition, (c)
certificates of deposit and Eurodollar time deposits with maturities of six
months or less from the date of acquisition, bankers' acceptances with
maturities not exceeding six months and overnight bank deposits, in each case
with any commercial bank organized under the laws of any country that is a
member of the Organization for Economic Cooperation and Development having
capital and surplus in excess of $500 million, (d) repurchase obligations with a
term of not more than seven days for underlying securities of the types
described in clauses (b) and (c) above entered into with any financial
institution meeting the qualifications specified in clause (c) above, (e)
commercial paper having the highest rating obtainable from Moody's Investors
Service, Inc. or Standard & Poor's Ratings Services and in each case maturing
within 180 days after the date of acquisition, (f) investments in commercial
paper, maturing not more than 180 days after the date of acquisition, issued by
a corporation organized and in existence under the laws of the United States of
America or any foreign country recognized by the United States of America with a
rating at the time as of which any investment therein is made of "P-1" (or
higher) according to Moody's or "A-1" (or higher) according to S & P, (g)
deposits available for withdrawal on demand with any commercial bank not meeting
the qualifications specified in clause (c) above, provided all such deposits do
not exceed $2.0 million in the aggregate at any one time, and (h) money market
mutual funds substantially all of the assets of which are of the type described
in the foregoing clauses (a) through (f) above.

        "Change of Control" means the occurrence of any of the following: (a)
the sale, lease, transfer, conveyance or other disposition (other than by way of
merger or consolidation), in one or a series of related transactions, of all or
substantially all of the assets of Parent or the Company and its Subsidiaries,
taken as a whole, (b) the adoption of a plan relating to the liquidation or
dissolution of the Company or Parent, (c) the consummation of any transaction
(including, without limitation, any merger or consolidation) the result of which
is that any "person" (as such term is used in Section 13(d)(3) of the Exchange
Act) becomes the "beneficial owner" (as such term is defined in Rule 13d-3 and
Rule 13d-5 under the Exchange Act), directly or indirectly through one or more
intermediaries, of more than 50% of the voting power of the outstanding voting
stock of the Company or Parent or (d) the first day on which

                                        3

<PAGE>

more than a majority of the members of the Board of Directors of the Company or
Parent are not Continuing Directors; provided, however, that a transaction in
which Parent or the Company becomes a Subsidiary of another Person (other than a
Person that is an individual) shall not constitute a Change of Control if (i)
the shareholders of Parent or the Company, as applicable, immediately prior to
such transaction "beneficially own" (as such term is defined in Rule 13d-3 and
Rule 13d-5 under the Exchange Act), directly or indirectly through one or more
intermediaries, at least a majority of the voting power of the outstanding
voting stock of Parent or the Company, as applicable, immediately following the
consummation of such transaction and (ii) immediately following the consummation
of such transaction, no "person" (as such term is defined above), other than
such other Person (but including the holders of the Equity Interests of such
other Person), "beneficially owns" (as such term is defined above), directly or
indirectly through one or more intermediaries, more than 50% of the voting power
of the outstanding voting stock of Parent or the Company, as applicable.

        "Clearstream Banking" means Clearstream Banking, S.A.

        "Common Stock" means the common stock of the Company, no par value per
share.

        "Consolidated Cash Flow" means, with respect to any Person for any
period, the Consolidated Net Income of such Person for such period plus, to the
extent deducted or excluded in calculating Consolidated Net Income for such
period, (a) an amount equal to any extraordinary loss plus any net loss realized
in connection with an Asset Sale, (b) provision for taxes based on income or
profits of such Person and its Restricted Subsidiaries, (c) Consolidated
Interest Expense of such Person and its Restricted Subsidiaries, and (d)
depreciation and amortization (including amortization of goodwill and other
intangibles but excluding amortization of prepaid cash expenses that were paid
in a prior period) of such Person and its Restricted Subsidiaries, in each case,
on a consolidated basis and determined in accordance with GAAP.

        "Consolidated Interest Coverage Ratio" means with respect to any Person
for any period, the ratio of the Consolidated Cash Flow of such Person for such
period to the Consolidated Interest Expense of such Person for such period;
provided, however, that the Consolidated Interest Coverage Ratio shall be
calculated giving pro forma effect to each of the following transactions as if
each such transaction had occurred at the beginning of the applicable
four-quarter reference period: (a) any incurrence, assumption, guarantee or
redemption by the Company or any of its Restricted Subsidiaries of any
Indebtedness (other than revolving credit borrowings) subsequent to the
commencement of the period for which the Consolidated Interest Coverage Ratio is
being calculated but prior to the date on which the event for which the
calculation of the Consolidated Interest Coverage Ratio is made (the
"Calculation Date"); (b) any acquisition that has been made by the Company or
any of its Restricted Subsidiaries, or approved and expected to be consummated
within 30 days of the Calculation Date, including, in each case, through a
merger or consolidation, and including any related financing transactions,
during the four-quarter reference period or subsequent to such reference period
and on or prior to the Calculation Date (in which case Consolidated Cash Flow
for such reference period shall be calculated without giving effect to clause
(c) of the proviso set forth in the definition of Consolidated Net Income); and
(c) any other transaction that may be given pro forma effect as determined in
good faith by a responsible financial or accounting officer of the Company;
provided, further, however, that (i) the Consolidated Cash Flow attributable to
discontinued operations, as determined in accordance with GAAP, and operations
or businesses disposed of prior to the Calculation Date, shall be excluded and
(ii) the Consolidated Interest Expense attributable to discontinued operations,
as determined in accordance with GAAP, and operations or businesses disposed of
prior to the Calculation Date, shall be excluded, but only to the extent that
the obligations giving rise to such Consolidated Interest Expense will not be
obligations of the referent Person or any of its Restricted Subsidiaries
following the Calculation Date.

                                        4

<PAGE>

        "Consolidated Interest Expense" means, with respect to any Person for
any period, the sum, without duplication, of (a) the consolidated interest
expense of such Person and its Restricted Subsidiaries for such period, whether
paid or accrued (including, without limitation, amortization of original issue
discount, non-cash interest payments, the interest component of any deferred
payment obligations, the interest component of all payments associated with
Capital Lease Obligations, commissions, discounts and other fees and charges
incurred in respect of letter of credit or bankers' acceptance financings, and
net payments (if any) pursuant to Hedging Obligations but excluding amortization
of debt issuance costs) and (b) the consolidated interest expense of such Person
and its Restricted Subsidiaries that was capitalized during such period, in each
case determined on a consolidated basis in accordance with GAAP.

        "Consolidated Net Income" means, with respect to any Person for any
period, the aggregate of the Net Income of such Person and its Restricted
Subsidiaries for such period, on a consolidated basis, determined in accordance
with GAAP, provided that (a) the Net Income (but not loss) of any Person that is
not a Restricted Subsidiary or that is accounted for by the equity method of
accounting shall be included only to the extent of the amount of dividends or
distributions paid in cash to the referent Person or a Restricted Subsidiary
thereof, (b) the Net Income of any Restricted Subsidiary shall be excluded to
the extent that the declaration or payment of dividends or similar distributions
by that Restricted Subsidiary of that Net Income is not at the date of
determination permitted without any prior governmental approval (that has not
been obtained) or, directly or indirectly, by operation of the terms of its
charter or any agreement, instrument, judgment, decree, order, statute, rule or
governmental regulation applicable to that Subsidiary or its stockholders, and
(c) the cumulative effect of a change in accounting principles shall be
excluded.

        "Consolidated Net Tangible Assets" means, with respect to any Person as
of any date, the sum of the amounts that would appear on a consolidated balance
sheet of such Person and its consolidated Restricted Subsidiaries as the total
assets of such Person and its consolidated Restricted Subsidiaries, determined
on a consolidated basis in accordance with GAAP and after deducting therefrom,
(a) to the extent otherwise included, unamortized debt discount and expenses and
other unamortized deferred charges, goodwill, patents, trademarks, service
marks, trade names, copyrights, licenses, organization or development expenses
and other intangible items and (b) the aggregate amount of liabilities of the
Company and its Restricted Subsidiaries which may be properly classified as
current liabilities (including tax accrued as estimated), determined on a
consolidated basis in accordance with GAAP.

        "Continuing Director" means, as of any date of determination, any member
of the Board of Directors who (a) was a member of the Board of Directors on the
Issue Date or (b) was nominated for election to the Board of Directors with the
approval of, or whose election to the Board of Directors was ratified by, at
least a majority of the Continuing Directors who were members of the Board of
Directors at the time of such nomination or election.

        "Corporate Trust Office of the Trustee" shall be at the address of the
Trustee specified in Section 12.02 hereof or such other address as to which the
Trustee may give notice to the Company.

        "Credit Facilities" means one or more debt facilities or commercial
paper facilities, in each case with banks, investment funds or other lenders
providing for revolving credit loans, term loans, receivables financings,
including through the sale of receivables to such lenders or to special purpose
entities formed to borrow from such lenders against such receivables or letters
of credit, in each case, as amended, restated, modified, renewed, refunded,
replaced or refinanced in whole or in part from time to time.

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

                                        5

<PAGE>

        "Default" means any event that is or with the passage of time or the
giving of notice or both would be an Event of Default.

        "Definitive Notes" means Notes that are in the form of Exhibit A-1
attached hereto (but without including the text referred to in footnotes 1 and 4
thereto).

        "Deposit" means the $231.7 million initially deposited with the escrow
agent under the Escrow Agreement, which at the time of deposit represented 101%
of the aggregate principal amount of the Offered Notes, plus accrued and unpaid
interest on the Notes, to, but not including, October 31, 2003, as such sum may
increase as a result of the investment and reinvestment thereof.

        "Depository" means, with respect to the Notes issuable or issued in
whole or in part in global form, the Person specified in Section 2.03 hereof as
the Depository with respect to the Notes, until a successor shall have been
appointed and become such pursuant to the applicable provision of this
Indenture, and, thereafter, "Depository" shall mean or include such successor.

        "Disqualified Stock" means any Capital Stock that, by its terms (or by
the terms of any security into which it is convertible or for which it is
exchangeable), or upon the happening of any event, matures (excluding any
maturity as a result of an optional redemption by the issuer thereof) or is
mandatorily redeemable, pursuant to a sinking fund obligation or otherwise, or
redeemable at the option of the holder thereof, in whole or in part, on or prior
to the date that is 91 days after the date on which the Notes mature or are
redeemed or retired in full; provided, however, that any Capital Stock that
would constitute Disqualified Stock solely because the holders thereof (or of
any security into which it is convertible or for which it is exchangeable) have
the right to require the issuer to repurchase such Capital Stock (or such
security into which it is convertible or for which it is exchangeable) upon the
occurrence of any of the events constituting an Asset Sale or a Change of
Control shall not constitute Disqualified Stock if such Capital Stock (and all
such securities into which it is convertible or for which it is exchangeable)
provides that the issuer thereof will not repurchase or redeem any such Capital
Stock (or any such security into which it is convertible or for which it is
exchangeable) pursuant to such provisions prior to compliance by the Company
with Section 4.10 or 4.15 of this Indenture, as the case may be.

        "Domestic Subsidiary" means any Restricted Subsidiary of the Company
that was formed under the laws of the United States or any state of the United
States or the District of Columbia or that guarantees or otherwise provides
direct credit support for any Indebtedness of the Company.

        "Equity Interests" means Capital Stock and all warrants, options or
other rights to acquire Capital Stock (but excluding any debt security that is
convertible into, or exchangeable for, Capital Stock).

        "Equity Offering" means any sale of Equity Interests (other than
Disqualified Stock) of the Company or Parent either pursuant to an offering
registered under the Securities Act or a private placement.

        "Escrow Agent" means Wells Fargo Bank, N.A., and any successor thereof
pursuant to the terms of the Escrow Agreement

        "Escrow Agreement" means the Escrow Agreement, dated as of April 17,
2003, among Frontier Escrow Corporation, the Trustee and the Escrow Agent.

        "Euroclear" means Morgan Guaranty Trust Company of New York, Brussels
office, as operator of the Euroclear system.

                                        6

<PAGE>

        "Event of Loss" means, with respect to any property or asset of the
Company or any Restricted Subsidiary, (a) any damage to such property or asset
that results in an insurance settlement with respect thereto on the basis of a
total loss or a constructive or compromised total loss or (b) the confiscation,
condemnation or requisition of title to such property or asset by any government
or instrumentality or agency thereof. An Event of Loss shall be deemed to occur
as of the date of the insurance settlement, confiscation, condemnation or
requisition of title, as applicable.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended.

        "Exchange Offer" means the offer that may be made by the Company
pursuant to a Registration Rights Agreement to exchange Series B Notes for
Series A Notes.

        "Exchange Offer Registration Statement" has the meaning set forth in the
Registration Rights Agreement.

        "Existing Indebtedness" means Indebtedness of the Company and its
Restricted Subsidiaries (other than Indebtedness under a Credit Facility) in
existence on the Issue Date, until such amounts are repaid.

        The term "fair market value" means, with respect to any asset or
Investment, the fair market value of such asset or Investment at the time of the
event requiring such determination, as determined in good faith by the Board of
Directors, or, with respect to any asset or Investment in excess of $10.0
million (other than cash or Cash Equivalents), as determined by a reputable
appraisal firm that is, in the judgment of such Board of Directors, qualified to
perform the task for which such firm has been engaged and independent with
respect to the Company.

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

        "GAAP" means generally accepted accounting principles generally accepted
in the United States of America set forth in the opinions and pronouncements of
the Accounting Principles Board of the American Institute of Certified Public
Accountants and statements and pronouncements of the Financial Accounting
Standards Board or in such other statements by such other entity as have been
approved by a significant segment of the accounting profession, which are in
effect from time to time.

        "Global Note" means, individually and collectively, an Unrestricted
Global Note, a Regulation S Temporary Global Note, a Regulation S Permanent
Global Note and a 144A Global Note.

        "Government Securities" means direct obligations of, or obligations
guaranteed by, the United States of America, and the payment for which the
United States pledges its full faith and credit.

        "Guarantee" means any Subsidiary Guarantee or the Parent Guarantee.

        "Guarantor" means each of Parent and any Subsidiary Guarantor and their
respective successors and assigns.

        "Hedging Obligations" means, with respect to any Person, the obligations
of such Person under (a) interest rate swap agreements, interest rate cap
agreements and interest rate collar agreements, but only to the extent that the
notional amounts of such agreements do not exceed 105% of the aggregate
principal amount of such Indebtedness to which such agreement relates, (b) other
agreements or arrangements designed to protect such Person against fluctuations
in interest rates, (c) any hedging

                                        7

<PAGE>

agreement or other arrangement, in each case that is designed to provide
protection against fluctuations in the price of crude oil and gasoline and other
refined products (in the ordinary course of business and not for speculative
purposes) and (d) any foreign currency futures contract, option or similar
agreement or arrangement designed to protect such Person against fluctuations in
foreign currency rates, in each case to the extent such obligations are incurred
in the ordinary course of business of such Person.

        "Holder" means a Person in whose name a Note is registered.

        "Indebtedness" means, with respect to any Person, any indebtedness of
such Person, whether or not contingent, in respect of borrowed money or
evidenced by bonds, debentures, notes or similar instruments or letters of
credit (or reimbursement agreements in respect thereof) or banker's acceptances
or representing Capital Lease Obligations or the balance deferred and unpaid of
the purchase price of any property or representing any Hedging Obligations,
except any such balance that constitutes an accrued expense or trade payable, if
and to the extent any of the foregoing indebtedness (other than letters of
credit and Hedging Obligations) would appear as a liability upon a balance sheet
of such Person prepared in accordance with GAAP. The amount of any Indebtedness
outstanding as of any date shall be (a) the accreted value thereof, in the case
of any Indebtedness that does not require current payments of interest, and (b)
the principal amount thereof, in the case of any other Indebtedness.

        "Indenture" means this Indenture, as amended or supplemented from time
to time.

        "Indirect Participant" means a Person who holds an interest through a
Participant.

        "Initial Purchaser" means each initial purchaser of Notes identified as
such in a Registration Rights Agreement.

        "Institutional Accredited Investor" means an "accredited investor" as
defined in Rule 501(a)(1), (2), (3) or (7) under the Securities Act.

        "Investments" means, with respect to any Person, all investments by such
Person in other Persons (including Affiliates) in the forms of direct or
indirect loans (including guarantees by the referent Person of, and Liens on any
assets of the referent Person securing, Indebtedness or other obligations of
other Persons), advances or capital contributions (excluding commission, travel
and similar advances to officers and employees made in the ordinary course of
business), purchases or other acquisitions for consideration of Indebtedness,
Equity Interests or other securities, together with all items that are or would
be classified as investments on a balance sheet prepared in accordance with
GAAP; provided, however, that the following shall not constitute Investments:
(i) extensions of trade credit or other advances to customers on commercially
reasonable terms in accordance with normal trade practices or otherwise in the
ordinary course of business, (ii) Hedging Obligations and (iii) endorsements of
negotiable instruments and documents in the ordinary course of business. If the
Company or any Restricted Subsidiary of the Company sells or otherwise disposes
of any Equity Interests of any direct or indirect Restricted Subsidiary of the
Company such that, after giving effect to any such sale or disposition, such
Person is no longer a Restricted Subsidiary of the Company, the Company shall be
deemed to have made an Investment on the date of any such sale or disposition
equal to the fair market value of the Equity Interests of such Restricted
Subsidiary not sold or disposed of in an amount determined as provided in the
final paragraph of the covenant described in Section 4.07 of this Indenture.

        "Issue Date" means the date on which the Offered Notes are issued
hereunder.

        "Legal Holiday" means a Saturday, a Sunday or a day on which banking
institutions in the City of Houston, Texas, the City of Fort Worth, Texas, the
City of Minneapolis, Minnesota, the City and State of

                                        8

<PAGE>

New York or at a place of payment are authorized by law, regulation or executive
order to remain closed. If a payment date is a Legal Holiday at a place of
payment, payment may be made at that place on the next succeeding day that is
not a Legal Holiday, and no interest shall accrue for the intervening period.

        "Lien" means, with respect to any asset, any mortgage, lien, pledge,
charge, security interest or encumbrance of any kind in respect of such asset,
whether or not filed, recorded or otherwise perfected under applicable law
(including any conditional sale or other title retention agreement, any lease in
the nature thereof, any option or other agreement to sell or give a security
interest in and any filing of or agreement to give any financing statement under
the Uniform Commercial Code (or equivalent statutes) of any jurisdiction other
than a precautionary financing statement respecting a lease not intended as a
security agreement).

        "Liquidated Damages" means all liquidated damages then owing to any
Holder pursuant to a Registration Rights Agreement.

        "Make-Whole Amount" with respect to a Note means an amount equal to the
excess, if any, of (i) the present value of the remaining interest, premium, if
any, and principal payments due on such Note as if such Note were redeemed on
April 15, 2008, computed using a discount rate equal to the Treasury Rate plus
50 basis points, over (ii) the outstanding principal amount of such Note.
"Treasury Rate" is defined as the yield to maturity at the time of the
computation of United States Treasury securities with a constant maturity (as
compiled by and published in the most recent Federal Reserve Statistical Release
H.15(519), which has become publicly available at least two Business Days prior
to the date of the redemption notice or, if such Statistical Release is no
longer published, any publicly available source of similar market date) most
nearly equal to the then remaining maturity of the Notes assuming redemption of
the Notes on April 15, 2008; provided, however, that if the Make-Whole Average
Life of such Note is not equal to the constant maturity of the United States
Treasury security for which a weekly average yield is given, the Treasury Rate
shall be obtained by linear interpolation (calculated to the nearest one-twelfth
of a year) from the weekly average yields of United States Treasury securities
for which such yields are given, except that if the Make-Whole Average Life of
such Notes is less than one year, the weekly average yield on actually traded
United States Treasury securities adjusted to a constant maturity of one year
shall be used. "Make-Whole Average Life" means the number of years (calculated
to the nearest one-twelfth) between the date of redemption and April 15, 2008.

        "Make-Whole Price" with respect to a Note means the greater of (i) the
sum of the outstanding principal amount and Make-Whole Amount of such Note, and
(ii) the redemption price of such Note on April 15, 2008, determined pursuant to
this Indenture (104.000% of the principal amount).

        "Moody's" means Moody's Investors Service, Inc.

        "Net Income" means, with respect to any Person, the net income (loss) of
such Person, determined in accordance with GAAP and before any reduction in
respect of preferred stock dividends, excluding, however, (a) any gain (but not
loss), together with any related provision for taxes on such gain (but not
loss), realized in connection with (i) any Asset Sale (including, without
limitation, dispositions pursuant to sale-and-leaseback transactions) or (ii)
the disposition of any securities by such Person or any of its Restricted
Subsidiaries or the extinguishment of any Indebtedness of such Person or any of
its Restricted Subsidiaries and (b) any extraordinary or nonrecurring gain (but
not loss), together with any related provision for taxes on such extraordinary
or nonrecurring gain (but not loss).

        "Net Proceeds" means the aggregate cash proceeds received by the Company
or any of its Restricted Subsidiaries in respect of any Asset Sale (including,
without limitation, any cash received upon the sale or other disposition of any
non-cash consideration received in any Asset Sale), net of (without

                                        9

<PAGE>

duplication) (a) the direct costs relating to such Asset Sale (including,
without limitation, legal, accounting and investment banking fees, sales
commissions, recording fees, title transfer fees, title insurance premiums,
appraiser fees and costs incurred in connection with preparing such asset for
sale) and any relocation expenses incurred as a result thereof, (b) taxes paid
or estimated to be payable as a result thereof (after taking into account any
available tax credits or deductions and any tax sharing arrangements), (c)
amounts required to be applied to the repayment of Indebtedness (other than
under a Credit Facility) secured by a Lien on the asset or assets that were the
subject of such Asset Sale and (d) any reserve established in accordance with
GAAP or any amount placed in escrow, in either case for adjustment in respect of
the sale price of such asset or assets, until such time as such reserve is
reversed or such escrow arrangement is terminated, in which case Net Proceeds
shall include only the amount of the reserve so reserved or the amount returned
to the Company or its Restricted Subsidiaries from such escrow arrangement, as
the case may be.

        "Non-Recourse Debt" means Indebtedness (a) as to which neither the
Company nor any of its Restricted Subsidiaries (i) provides credit support of
any kind (including any undertaking, agreement or instrument that would
constitute Indebtedness) or is otherwise directly or indirectly liable (as a
guarantor or otherwise) or (ii) constitutes the lender, (b) no default with
respect to which (including any rights that the holders thereof may have to take
enforcement action against an Unrestricted Subsidiary) would permit (upon
notice, lapse of time or both) the holders of Indebtedness of the Company or any
of its Restricted Subsidiaries to declare a default on such Indebtedness or
cause the payment thereof to be accelerated or payable prior to its Stated
Maturity and (c) as to which the lenders have been notified in writing that they
will not have any recourse to the stock or assets of the Company or any of its
Restricted Subsidiaries, except to the extent of any Indebtedness incurred by
the Company or any of its Restricted Subsidiaries in accordance with clause
(a)(i) above.

        "Non-U.S. Person" means a Person who is not a U.S. Person.

        "Note Custodian" means the Trustee, as custodian with respect to the
Notes in global form, or any successor entity thereto.

        "Obligations" means any principal, interest, penalties, fees,
indemnifications, reimbursements, damages and other liabilities payable under
the documentation governing any Indebtedness.

        "Offered Notes" has the meaning set forth in Section 2.02 hereof.

        "Officer" means, with respect to any Person, the Chairman of the Board,
the Chief Executive Officer, the President, the Chief Operating Officer, the
Chief Financial Officer, the Treasurer, any Assistant Treasurer, the Controller,
the Secretary, any Assistant Secretary or any Vice-President of such Person.

        "Officers' Certificate" means a certificate signed on behalf of the
Company by two Officers of the Company, one of whom must be the principal
executive officer, the principal financial officer, the treasurer or the
principal accounting officer of the Company, that meets the requirements of
Section 12.05 hereof.

        "Opinion of Counsel" means an opinion from legal counsel who is
reasonably acceptable to the Trustee, that meets the requirements of Section
12.05 hereof. The counsel may be an employee of or counsel to the Company, any
Subsidiary of the Company, Parent or the Trustee.

        "Parent Guarantee" means the joint and several Guarantee by Parent of
the Company's obligations under the Notes, such Guarantee to be issued upon
consummation of the Merger.

                                       10

<PAGE>

        "Pari Passu Indebtedness" means, with respect to any Net Proceeds from
Asset Sales, Indebtedness of the Company and its Restricted Subsidiaries the
terms of which require the Company or such Restricted Subsidiary to apply such
Net Proceeds to offer to repurchase such Indebtedness.

        "Participant" means with respect to DTC, Euroclear or Clearstream
Banking, a Person who has an account with DTC, Euroclear or Clearstream Banking,
respectively (and, with respect to DTC, shall include Euroclear and Clearstream
Banking).

        "Permitted Indebtedness" means:

                (a)     the incurrence by the Company or a Restricted Subsidiary
        of additional Indebtedness under any Working Capital Facility in an
        aggregate principal amount at any one time outstanding not to exceed the
        greater of (i) $250.0 million and (ii) an amount equal to the sum of 95%
        of the book value of accounts receivable (less allowance for doubtful
        accounts) and 90% of the inventory (less applicable reserves) of the
        Company and its Restricted Subsidiaries, calculated on a consolidated
        basis and in accordance with GAAP, plus $10.0 million and any fees,
        premiums, expenses (including costs of collection), indemnities and
        similar amounts payable in connection with such Indebtedness, and less
        any amounts repaid permanently in accordance with Section 4.10 hereof;

                (b)     the incurrence by the Company and its Restricted
        Subsidiaries of Existing Indebtedness;

                (c)     the incurrence by the Company and its Restricted
        Subsidiaries of Hedging Obligations;

                (d)     the incurrence by the Company and the Guarantors of
        Indebtedness represented by the Notes to be issued on the date of this
        Indenture and the related Subsidiary Guarantees and the Exchange Notes
        and related Subsidiary Guarantees to be issued pursuant to the
        Registration Rights Agreement;

                (e)     the incurrence of intercompany Indebtedness between or
        among the Company and any of its Restricted Subsidiaries, provided that
        (i) if the Company or any Guarantor is the obligor on such Indebtedness,
        such Indebtedness is expressly subordinate to the payment in full of all
        obligations with respect to the Notes, in the case of the Company, and
        the Subsidiary Guarantee, in the case of a Guarantor and (ii) (A) any
        subsequent issuance or transfer of Equity Interests that results in any
        such Indebtedness being held by a Person other than the Company or a
        Restricted Subsidiary of the Company, or (B) any sale or other transfer
        of any such Indebtedness to a Person that is neither the Company nor a
        Restricted Subsidiary of the Company, will be deemed, in each case, to
        constitute an incurrence of such Indebtedness by the Company or such
        Restricted Subsidiary, as the case may be, that was not permitted by
        this clause (e);

                (f)     the incurrence by Foreign Subsidiaries of Indebtedness
        in an aggregate amount at any time outstanding under this clause (f) not
        to exceed $10.0 million;

                (g)     Indebtedness in respect of bid, performance or surety
        bonds issued for the account of the Company or any Restricted Subsidiary
        thereof in the ordinary course of business, including guarantees or
        obligations of the Company or any Restricted

                                       11

<PAGE>

        Subsidiary thereof with respect to letters of credit supporting such
        bid, performance or surety obligations (in each case other than for an
        obligation for money borrowed);

                (h)     the incurrence by the Company or any of its Restricted
        Subsidiaries of Permitted Refinancing Indebtedness in exchange for, or
        the net proceeds of which are used to extend, refinance, renew, replace,
        defease or refund Indebtedness that was permitted by this Indenture to
        be incurred (other than pursuant to clause (a) or (f) of this
        definition);

                (i)     incurrence by any Subsidiary of the Company of a
        Subsidiary Guarantee;

                (j)     incurrence of Non-Recourse Debt; or

                (k)     the guarantee by the Company or any of the Guarantors of
        Indebtedness of the Company or a Subsidiary of the Company that was
        permitted to be incurred by Section 4.09 hereof;

                (l)     the accrual of interest, the accretion or amortization
        of original issue discount, the payment of interest on any Indebtedness
        in the form of additional Indebtedness with the same terms, and the
        payment of dividends on Disqualified Stock in the form of additional
        shares of the same class of Disqualified Stock will not be deemed to be
        an incurrence of Indebtedness or an issuance of Disqualified Stock for
        purposes of Section 4.09 hereof; provided, in each such case, that the
        amount hereof is included in Consolidated Interest Expense; and

                (m)     incurrence by the Company or any Restricted Subsidiary
        of any additional Indebtedness not to exceed $25.0 million at any time
        outstanding.

        "Permitted Investments" means (a) any Investment in the Company or in a
Restricted Subsidiary of the Company, (b) any Investment in Cash Equivalents,
(c) any Investment by the Company or any Restricted Subsidiary of the Company in
a Person if as a result of such Investment (i) such Person becomes a Restricted
Subsidiary of the Company or (ii) such Person is merged, consolidated or
amalgamated with or into, or transfers or conveys all or substantially all of
its assets to, or is liquidated into, the Company or a Restricted Subsidiary of
the Company, (d) any Investment made as a result of the receipt of non-cash
consideration from (i) an Asset Sale that was made pursuant to and in compliance
with Section 4.10 hereof or (ii) a disposition of assets that does not
constitute an Asset Sale, (e) acquisition of assets solely in exchange for the
issuance of Equity Interests (other than Disqualified Stock) of the Company, (f)
any Investments received in compromise of obligations of such Persons incurred
in the ordinary course of trade creditors or customers that were incurred in the
ordinary course of business, including pursuant to any plan of reorganization or
similar arrangement upon the bankruptcy or insolvency of any trade creditor or
customer, (g) Hedging Obligations, and (h) Investments in a Person engaged in
the Principal Business, provided that the aggregate amount of such Investments
pursuant to this clause (h) in Persons that are not Restricted Subsidiaries of
the Company shall not exceed $50.0 million at any one time.

        "Permitted Liens" means (a) Liens securing Indebtedness incurred
pursuant to clause (a) of the definition of "Permitted Indebtedness," (b) Liens
in favor of the Company or any of the Guarantors, (c) Liens on property of a
Person existing at the time such Person is merged into or consolidated with the
Company or any Restricted Subsidiary of the Company, provided that such Liens
were in existence prior to the contemplation of such merger or consolidation and
do not extend to any property other than those of the Person merged into or
consolidated with the Company or any of its Restricted Subsidiaries, (d)

                                       12

<PAGE>

Liens on property existing at the time of acquisition thereof by the Company or
any Restricted Subsidiary of the Company, provided that such Liens were in
existence prior to the contemplation of such acquisition and do not extend to
any other property, (e) Liens to secure the performance of statutory
obligations, surety or appeal bonds, bid or performance bonds, insurance
obligations or other obligations of a like nature incurred in the ordinary
course of business, (f) Liens securing Hedging Obligations, (g) Liens existing
on the Issue Date, (h) Liens securing Non-Recourse Debt, (i) any interest or
title of a lessor under a Capital Lease Obligation or an operating lease, (j)
Liens arising by reason of deposits necessary to obtain standby letters of
credit in the ordinary course of business (including deposits necessary to
obtain standby letters of credit), (k) Liens incurred or deposits made in the
ordinary course of business in connection with workers' compensation,
unemployment insurance and other types of social security and related benefits,
(l) easements, rights of way restrictions and other similar charges or
encumbrances not interfering in any material respect with the business of the
Company or any Restricted Subsidiary, (m) any other Liens imposed by operation
of law which do not materially affect the Company's or any Guarantor's ability
to perform its obligations under the Notes or any Subsidiary Guarantee, (n) any
attachment or judgment Lien, unless the judgment it secures shall not, within 60
days after the entry thereof, have been discharged or execution thereof stayed
pending appeal, or shall not have been discharged within 60 days after the
expiration of any such stay, (o) Liens to secure Purchase Money Indebtedness,
which Liens shall not extend to any other property or assets of the Company or a
Restricted Subsidiary (other than any associated accounts, contracts and
insurance proceeds), (p) Liens securing Permitted Refinancing Indebtedness with
respect to any Indebtedness referred to in clause (o) above, and (q) Liens
incurred in the ordinary course of business of the Company or any Restricted
Subsidiary of the Company with respect to obligations that do not exceed $5.0
million at any one time outstanding and that (i) are not incurred in connection
with the borrowing of money or the obtaining of advances or credit (other than
trade credit in the ordinary course of business) and (ii) do not in the
aggregate materially detract from the value of the property or materially impair
the use thereof in the operation of business by the Company or such Restricted
Subsidiary.

        "Permitted Refinancing Indebtedness" means any Indebtedness of the
Company or any of its Restricted Subsidiaries issued in exchange for, or the net
proceeds of which are used to extend, refinance, renew, replace, defease or
refund other Indebtedness of the Company or any of its Restricted Subsidiaries;
provided, however, that (a) the principal amount (or accreted value, if
applicable) of such Permitted Refinancing Indebtedness does not exceed the
principal amount of (or accreted value, if applicable), plus premium, if any,
and accrued interest on, the Indebtedness so extended, refinanced, renewed,
replaced, defeased or refunded (plus the amount of reasonable expenses incurred
in connection therewith), (b) such Permitted Refinancing Indebtedness has a
final maturity date no earlier than the final maturity date of, and has a
Weighted Average Life to Maturity equal to or greater than the Weighted Average
Life to Maturity of, the Indebtedness being extended, refinanced, renewed,
replaced, defeased or refunded, (c) if the Indebtedness being extended,
refinanced, renewed, replaced, defeased or refunded is subordinated in right of
payment to the Notes, such Permitted Refinancing Indebtedness is subordinated in
right of payment to the Notes on terms at least as favorable, taken as a whole,
to the Holders of Notes as those contained in the documentation governing the
Indebtedness being extended, refinanced, renewed, replaced, defeased or refunded
and (d) such Indebtedness is incurred either by the Company or by the Restricted
Subsidiary that is the obligor on the Indebtedness being extended, refinanced,
renewed, replaced, defeased or refunded; provided, however, that a Restricted
Subsidiary that is also a Guarantor may guarantee Permitted Refinancing
Indebtedness incurred by the Company, whether or not such Restricted Subsidiary
was an obligor or guarantor of the Indebtedness being extended, refinanced,
renewed, replaced, defeased or refunded; provided, further, however, that if
such Permitted Refinancing Indebtedness is subordinated to the Notes, such
guarantee shall be subordinated to such Restricted Subsidiary's Subsidiary
Guarantee to at least the same extent.

                                       13

<PAGE>

        "Person" means any individual, corporation, partnership, limited
liability company, joint venture, association, joint-stock company, trust,
unincorporated organization or government or agency or political subdivision
thereof (including any subdivision or ongoing business of any such entity or
substantially all of the assets of any such entity, subdivision or business).

        "Principal Business" means (a) the business of the exploration for, and
development, acquisition, production, processing, marketing, refining, storage
and transportation of, hydrocarbons, (b) any related energy and natural resource
business, (c) any business currently engaged in by the Company or its
Subsidiaries, (d) convenience stores, retail service stations, truck stops and
other public accommodations in connection therewith and (e) any activity or
business that is a reasonable extension, development or expansion of any of the
foregoing.

        "Private Placement Legend" means the legend set forth in Section
2.06(g)(i) to be placed on all Notes issued under this Indenture except where
otherwise permitted by the provisions of this Indenture.

        "Purchase Money Indebtedness" means Indebtedness incurred for the
purpose of (a) financing all or any part of the purchase price of any real or
personal property or assets incurred prior to, at the time of, or within 120
days after, the acquisition of such property or (ii) financing all or any part
of the cost of construction of any such property or assets, provided that the
amount of any such financing shall not exceed the amount expended in the
acquisition of, or the construction of, such property or assets.

        "QIB" means a "qualified institutional buyer" as defined in Rule 144A
under the Securities Act.

        "Registration Rights Agreement" means the Registration Rights Agreement,
dated as of April 17, 2003, by and among Frontier Oil Corporation, Parent and
the Initial Purchasers named therein, as such agreement may be amended, modified
or supplemented from time to time, or one or more registration rights agreements
among the Company, the Guarantors and the other parties thereto, as such
agreement(s) may be amended, modified or supplemented from time to time,
relating to rights given by the Company to the purchasers of Series A Notes sold
in reliance on Rule 144A or another exemption from the registration requirements
of the Securities Act to register such Notes under the Securities Act.

        "Regulation S" means Regulation S under the Securities Act.

        "Regulation S Global Note" means a Regulation S Temporary Global Note or
Regulation S Permanent Global Note, as appropriate.

        "Regulation S Permanent Global Note" means a permanent senior Global
Note that contains the paragraph referred to in footnote 1 and the additional
schedule referred to in footnote 4 to the form of the Note attached hereto as
Exhibit A-1, and that is deposited with the Note Custodian and registered in the
name of the Depository, representing a series of Notes sold in reliance on
Regulation S.

        "Regulation S Temporary Global Note" means a single temporary senior
Global Note in the form of the Note attached hereto as Exhibit A-2 that is
deposited with the Note Custodian and registered in the name of the Depository,
representing a series of Notes sold in reliance on Regulation S.

        "Responsible Officer," when used with respect to the Trustee, means any
officer within the Corporate Trust Department of the Trustee (or any successor
department of the Trustee) or any other 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 to whom such matter is referred because of his knowledge of
and familiarity with the particular subject.

                                       14

<PAGE>

        "Restricted Beneficial Interest" means any beneficial interest of a
Participant or Indirect Participant in a Restricted Global Note.

        "Restricted Definitive Notes" means the Definitive Notes that are
required to bear the legend set forth in Section 2.06(g) hereof.

        "Restricted Global Notes" means the 144A Global Note and the Regulation
S Global Note, each of which is required to bear the legend set forth in Section
2.06(g) hereof.

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

        "Restricted Period" means the 40-day distribution compliance period as
defined in Regulation S.

        "Restricted Subsidiary" of a Person means any Subsidiary of such Person
that is not an Unrestricted Subsidiary.

        "Rule 144A" means Rule 144A promulgated under the Securities Act.

        "S&P" means Standard & Poor's Ratings Group.

        "SEC" or "Commission" means the Securities and Exchange Commission.

        "Securities Act" means the Securities Act of 1933, as amended.

        "Shelf Registration Statement" means the Shelf Registration Statement as
defined in the Registration Rights Agreement.

        "Significant Subsidiary" means any Subsidiary that would be a
"significant subsidiary" as defined in Article 1, Rule 1-02 of Regulation S-X,
promulgated pursuant to the Securities Act, as such Regulation is in effect on
the date hereof.

        "Stated Maturity" means, with respect to any installment of interest or
principal on any series of Indebtedness, the date on which such payment of
interest or principal was scheduled to be paid in the original documentation
governing such Indebtedness, and shall not include any contingent obligations to
repay, redeem or repurchase any such interest or principal prior to the date
originally scheduled for the payment thereof.

        "Subsidiary" means, with respect to any Person, (a) any corporation,
association or other business entity of which more than 50% of the total voting
power of shares of Capital Stock entitled (without regard to the occurrence of
any contingency) to vote in the election of directors, managers or trustees
thereof is at the time owned or controlled, directly or indirectly, by such
Person or one or more of the other Subsidiaries of that Person (or a combination
thereof) and (b) any partnership (i) the sole general partner or the managing
general partner of which is such Person or a Subsidiary of such Person or (ii)
the only general partners of which are such Person or of one or more
Subsidiaries of such Person (or any combination thereof).

        "Subsidiary Guarantee" means a joint and several Guarantee by a
Subsidiary Guarantor pursuant to Article 10 hereof of the Company's obligations
under the Notes, such Guarantee to be issued upon or after consummation of the
Merger.

                                       15

<PAGE>

        "Subsidiary Guarantor" means any Subsidiary of the Company that executes
a supplemental indenture and a Guarantee in accordance with the provisions of
this Indenture, until such time as any such Subsidiary shall be released and
relieved of its obligations pursuant to Section 10.04 or 10.05 hereof.

        "TIA" means the Trust Indenture Act of 1939 (15 U.S.C. Sections
77aaa-77bbbb) as in effect on the date on which this Indenture is qualified
under the TIA.

        "Transfer Restricted Securities" means securities (other than the
Offered Notes) that bear or are required to bear the legend set forth in Section
2.06(g) hereof.

        "Trustee" means the party named as such in the first paragraph of this
Indenture until a successor replaces it in accordance with the applicable
provisions of this Indenture and thereafter means the successor serving
hereunder.

        "Unrestricted Definitive Note" means one or more Definitive Notes that
do not bear and are not required to bear the Private Placement Legend.

        "Unrestricted Global Notes" means one or more Global Notes that do not
and are not required to bear the legend set forth in Section 2.06(g) hereof.

        "Unrestricted Subsidiary" means any Subsidiary that is designated by the
Board of Directors as an Unrestricted Subsidiary pursuant to a resolution of the
Board of Directors, but only to the extent that such Subsidiary at the time of
such designation (a) has no Indebtedness other than Non-Recourse Debt, (b) is
not party to any agreement, contract, arrangement or understanding with the
Company or any Restricted Subsidiary of the Company unless such agreement,
contract, arrangement or understanding does not violate the terms of this
Indenture described in Section 4.11 hereof, and (c) is a Person with respect to
which neither the Company nor any of its Restricted Subsidiaries has any direct
or indirect obligation (i) to subscribe for additional Equity Interests or (ii)
to maintain or preserve such Person's financial condition or to cause such
Person to achieve any specified levels of operating results, in each case,
except to the extent otherwise permitted by this Indenture. Any such designation
by the Board of Directors shall be evidenced to the Trustee by filing with the
Trustee a certified copy of the resolution of the Board of Directors giving
effect to such designation and an Officers' Certificate certifying that such
designation complied with the foregoing conditions and was permitted by Section
4.07 hereof. If, at any time, any Unrestricted Subsidiary would fail to meet the
foregoing requirements as an Unrestricted Subsidiary, it shall thereafter cease
to be an Unrestricted Subsidiary for purposes of this Indenture and any
Indebtedness of such Subsidiary shall be deemed to be incurred by a Restricted
Subsidiary of the Company as of such date (and, if such Indebtedness is not
permitted to be incurred as of such date pursuant to Section 4.09 hereof, the
Company shall be in default of such covenant). The Board of Directors may at any
time designate any Unrestricted Subsidiary to be a Restricted Subsidiary,
provided that such designation shall be deemed to be an incurrence of
Indebtedness by a Restricted Subsidiary of the Company of any outstanding
Indebtedness of such Unrestricted Subsidiary and such designation shall only be
permitted if (A) such Indebtedness is permitted by Section 4.09 hereof,
calculated on a pro forma basis as if such designation had occurred at the
beginning of the four-quarter reference period, and (B) no Default or Event of
Default would be in existence following such designation.

        "U.S. Person" means a U.S. Person as defined in Rule 902(o) under the
Securities Act.

        "Weighted Average Life to Maturity" means, when applied to any
Indebtedness at any date, the number of years obtained by dividing (a) the sum
of the products obtained by multiplying (i) the amount of each then remaining
installment, sinking fund, serial maturity or other required payments of
principal, including payment at final maturity, in respect thereof, by (ii) the
number of years (calculated to the

                                       16

<PAGE>

nearest one-twelfth) that will elapse between such date and the making of such
payment, by (b) the then outstanding principal amount of such Indebtedness.

        "Working Capital Facility" means any working capital facilities entered
into by the Company or any of its Restricted Subsidiaries, including any related
notes, guarantees, collateral documents, instruments and agreements executed in
connection therewith, in each case as amended, restated, modified, supplemented,
extended, renewed, replaced, refinanced or restructured from time to time,
whether by the same or any other agent or agents, lender or group of lenders,
whether represented by one or more agreements and whether one or more
Subsidiaries are borrowers, or guarantors thereunder or parties thereto.

Section 1.02    Other Definitions.

                                                                      Defined in
Term                                                                    Section
-----                                                                 ----------
"Affiliate Transaction"................................................  4.11
"Asset Sale Offer".....................................................  3.09
"Change of Control Offer"..............................................  4.15
"Authentication Order".................................................  2.02
"Change of Control Payment"............................................  4.15
"Change of Control Payment Date".......................................  4.15
"Covenant Defeasance"..................................................  8.03
"DTC" .................................................................  2.03
"Escrow Corp. Merger".................................................. Preamble
"Event of Default".....................................................  6.01
"Excess Proceeds"......................................................  4.10
"Frontier Merger"...................................................... Preamble
"Holly Merger"......................................................... Preamble
"incur" or "incurrence"................................................  4.09
"Legal Defeasance".....................................................  8.02
"Merger"............................................................... Preamble
"Offer Amount" ........................................................  3.09
"Offer Period" ........................................................  3.09
"Parent"............................................................... Preamble
"Paying Agent".........................................................  2.03
"Payment Default" .....................................................  6.01
"Purchase Date" .......................................................  3.09
"Registrar" ...........................................................  2.03
"Restricted Payments"..................................................  4.07
"Special Mandatory Redemption Date"....................................  3.08

Section 1.03    Incorporation by Reference of Trust Indenture Act.

        Whenever this Indenture refers to a provision of the TIA, the provision
is incorporated by reference in and made a part of this Indenture. Any terms
incorporated in this Indenture that are defined by the TIA, defined by TIA
reference to another statute or defined by SEC rule under the TIA have the
meanings so assigned to them.

                                       17

<PAGE>

Section 1.04    Rules of Construction.

        Unless the context otherwise requires:

                (1)     a term has the meaning assigned to it;

                (2)     an accounting term not otherwise defined has the meaning
        assigned to it in accordance with GAAP;

                (3)     "or" is not exclusive;

                (4)     words in the singular include the plural, and in the
        plural include the singular;

                (5)     provisions apply to successive events and transactions;
        and

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

                                   ARTICLE 2.
                                    THE NOTES

Section 2.01    Form and Dating.

        The Notes and the Trustee's certificate of authentication shall be
substantially in the form of Exhibit A-1 or Exhibit A-2 hereto, as applicable.
The Notes may have notations, legends or endorsements required by law, stock
exchange rule or usage. Each Note shall be dated the date of its authentication.
The Notes shall be issued in denominations of $1,000 and integral multiples
thereof.

        Regardless of their respective dates of original issue, all of the
Series A Notes and the Series B Notes shall be considered collectively to be a
single class for all purposes of this Indenture, including, without limitation,
waivers, amendments, redemptions and offers to purchase.

        The terms and provisions contained in the Notes shall constitute, and
are hereby expressly made, a part of this Indenture, and the Company and the
Trustee, by their execution and delivery of this Indenture or any supplemental
indenture, and the Guarantors by their execution and delivery of the Guarantees
and any supplemental indenture, expressly agree to such terms and provisions and
to be bound thereby. However, to the extent any provision of any Note conflicts
with the express provisions of this Indenture, the provisions of this Indenture
shall govern and be controlling.

        (a)     Global Notes. Offered Notes shall be issued initially in the
form of one or more Unrestricted Global Notes, which shall be deposited on
behalf of the purchasers of the Offered Notes represented thereby with the Note
Custodian and registered in the name of the Depository or a nominee of the
Depository, duly executed by the Company and authenticated by the Trustee as
hereinafter provided. The aggregate principal amount of the Unrestricted Global
Notes may from time to time be increased or decreased by adjustments made on the
records of the Trustee and the Depository or its nominee, as the case may be, in
connection with transfers of interests as hereinafter provided.

        Except as provided in Section 2.01(c), Series A Notes offered and sold
to QIBs in reliance on Rule 144A shall be issued initially in the form of one or
more 144A Global Notes, which shall be

                                       18

<PAGE>

deposited on behalf of the purchasers of the Series A Notes represented thereby
with the Note Custodian and registered in the name of the Depository or a
nominee of the Depository, duly executed by the Company and authenticated by the
Trustee as hereinafter provided. The aggregate principal amount of the 144A
Global Notes may from time to time be increased or decreased by adjustments made
on the records of the Trustee and the Depository or its nominee, as the case may
be, in connection with transfers of interests as hereinafter provided.

        Series A Notes offered and sold in reliance on Regulation S, if any,
shall be issued initially in the form of the Regulation S Temporary Global Note,
which shall be deposited on behalf of the purchasers of the Series A Notes
represented thereby with the Note Custodian and registered in the name of the
Depository or the nominee of the Depository for the accounts of designated
agents holding on behalf of Euroclear or Clearstream Banking, duly executed by
the Company and authenticated by the Trustee as hereinafter provided. The
Restricted Period shall be terminated upon the receipt by the Trustee of (i) a
written certificate from the Depository, together with copies of certificates
from Euroclear and Clearstream Banking certifying that they have received
certification of non-United States beneficial ownership of 100% of the aggregate
principal amount of the Regulation S Temporary Global Note (except to the extent
of any beneficial owners thereof who acquired an interest therein pursuant to
another exemption from registration under the Securities Act and who will take
delivery of a beneficial ownership interest in a 144A Global Note, all as
contemplated by Section 2.06(b) hereof), and (ii) an Officers' Certificate from
the Company. Following the termination of the 40-day restricted period,
beneficial interests in the Regulation S Temporary Global Note shall be
exchanged for beneficial interests in one or more Regulation S Permanent Global
Notes pursuant to the Applicable Procedures. Simultaneously with the
authentication of Regulation S Permanent Global Notes, the Trustee shall cancel
the Regulation S Temporary Global Note. The aggregate principal amount of the
Regulation S Temporary Global Note and the Regulation S Permanent Global Notes
may from time to time be increased or decreased by adjustments made on the
records of the Trustee and the Depository or its nominee, as the case may be, in
connection with transfers of interests as hereinafter provided.

        Each Global Note shall represent such of the outstanding Notes as shall
be specified therein and each shall provide that it shall represent the
aggregate amount of outstanding Notes from time to time endorsed thereon and
that the aggregate amount of outstanding Notes represented thereby may from time
to time be reduced or increased, as appropriate, to reflect exchanges,
redemptions and transfers of interests. Any endorsement of a Global Note to
reflect the amount of any increase or decrease in the amount of outstanding
Notes represented thereby shall be made by the Trustee or the Note Custodian, at
the direction of the Trustee, in accordance with instructions given by the
Holder thereof as required by Section 2.06 hereof.

        The provisions of the "Operating Procedures of the Euroclear System" and
"Terms and Conditions Governing Use of Euroclear" and the "General Terms and
Conditions of Clearstream Banking" and "Customer Handbook" of Clearstream
Banking shall be applicable to interests in the Regulation S Temporary Global
Note and the Regulation S Permanent Global Notes, if any, that are held by
Participants through Euroclear or Clearstream Banking. The Trustee shall have no
obligation to notify Holders of any such procedures or to monitor or enforce
compliance with the same.

        (b)     Book-Entry Provisions. Participants shall have no rights either
under this Indenture with respect to any Global Note held on their behalf by the
Depository or by the Note Custodian as custodian for the Depository or under
such Global Note, and the Depository may be treated by the Company, the Trustee
and any Agent of the Company or the Trustee as the absolute owner of such Global
Note for all purposes whatsoever. Notwithstanding the foregoing, nothing herein
shall prevent the Company, the Trustee or any Agent of the Company or the
Trustee from giving effect to any written certification, proxy or other
authorization furnished by the Depository or impair, as between the Depository
and its

                                       19

<PAGE>

Participants, the operation of customary practices of such Depository governing
the exercise of the rights of an owner of a beneficial interest in any Global
Note.

        (c)     Definitive Notes. Series A Notes offered and sold to
Institutional Accredited Investors who are not QIBs otherwise than in reliance
on Regulation S, if any, or to QIBs who elect to take their Series A Notes in
definitive form shall be issued initially in the form of Definitive Notes, duly
executed by the Company and authenticated by the Trustee as hereinafter
provided.

Section 2.02    Execution and Authentication.

        One Officer shall sign the Notes for the Company by manual or facsimile
signature.

        If an Officer whose signature is on a Note no longer holds that office
at the time a Note is authenticated, the Note shall nevertheless be valid.

        A Note shall not be valid until authenticated by the manual signature of
an authorized signatory of the Trustee. Such signature shall be conclusive
evidence that the Note has been authenticated under this Indenture. The form of
Trustee's certificate of authentication to be borne by the Notes shall be
substantially as set forth in Exhibit A-1 or Exhibit A-2 hereto, as applicable.

        Each Note shall be dated the date of its authentication.

        The Trustee shall authenticate (i) the Series A Notes for original issue
on the Issue Date in the aggregate principal amount of $220,000,000 (the
"Offered Notes"), (ii) additional Series A Notes for original issue from time to
time after the consummation of the Escrow Corp. Merger in such additional
principal amounts as may be set forth in an Authentication Order (as defined
below) and (iii) the Series B Notes from time to time for issue only in exchange
for a like principal amount of Series A Notes originally issued as Transfer
Restricted Securities, in each case upon a written order of the Company signed
by one Officer, which written order shall specify (a) the amount of Notes to be
authenticated and the date of original issue thereof, (b) whether the Notes are
Series A Notes or Series B Notes, (c) whether or not the Notes are Transfer
Restricted Securities and (d) the amount of Notes to be issued in global form or
definitive form (the "Authentication Order").

        The Trustee may appoint an authenticating agent acceptable to the
Company to authenticate Notes. An authenticating agent may authenticate Notes
whenever the Trustee may do so. Each reference in this Indenture to
authentication by the Trustee includes authentication by such agent. An
authenticating agent has the same rights as an Agent to deal with Holders, the
Company, any Guarantor or any Affiliate of the Company.

Section 2.03    Registrar and Paying Agent.

        The Company shall maintain an office or agency where Notes may be
presented for registration of transfer or for exchange ("Registrar") and an
office or agency in the Borough of Manhattan, the City and State of New York
where Notes may be presented for payment ("Paying Agent"). The Registrar shall
keep a register of the Notes and of their transfer and exchange. The Company may
appoint one or more co-registrars and one or more additional paying agents in
the Borough of Manhattan, the City and State of New York. The term "Registrar"
includes any co-registrar and the term "Paying Agent" includes any additional
paying agent. The Company may change any Paying Agent or Registrar without
notice to any Holder. The Company shall notify the Trustee in writing of the
name and address of any Agent not a party to this Indenture. If the Company
fails to appoint or maintain another entity as Registrar or Paying Agent, the
Trustee, acting through its office in the Borough of Manhattan, the City and
State of New

                                       20

<PAGE>

York, shall act as such. The Company shall enter into an appropriate agency
agreement with any Agent not a party to this Indenture, and such agreement shall
incorporate the TIA's provisions of this Indenture that relate to such Agent.
None of the Company, any of its Subsidiaries or Parent may act as Paying Agent
or Registrar.

        The Company initially appoints The Depository Trust Company ("DTC") to
act as Depository with respect to the Global Notes.

        The Company initially appoints the Trustee to act as the Registrar and
Paying Agent and to act as Note Custodian with respect to the Global Notes.

Section 2.04    Paying Agent to Hold Money in Trust.

        The Company shall require each Paying Agent other than the Trustee to
agree in writing that the Paying Agent will hold in trust for the benefit of
Holders or the Trustee all money held by the Paying Agent for the payment of
principal of or premium, interest or Liquidated Damages, if any, on the Notes,
and will notify the Trustee of any default by the Company in making any such
payment. While any such default continues, the Trustee may require a Paying
Agent to pay all money held by it to the Trustee. The Company at any time may
require a Paying Agent to pay all money held by it to the Trustee. Upon payment
over to the Trustee, the Paying Agent shall have no further liability for the
money. Upon any bankruptcy or reorganization proceedings relating to the
Company, the Trustee shall serve as Paying Agent for the Notes.

Section 2.05    Holder Lists.

        The Trustee shall preserve in as current a form as is reasonably
practicable the most recent list available to it of the names and addresses of
all Holders and shall otherwise comply with TIA Section 312(a). If the Trustee
is not the Registrar, the Company shall furnish to the Trustee at least seven
Business Days before each interest payment date and at such other times as the
Trustee may request in writing, a list in such form and as of such date as the
Trustee may reasonably require of the names and addresses of the Holders of
Notes, and the Company shall otherwise comply with TIA Section 312(a).

Section 2.06    Transfer and Exchange.

        (a)     Transfer and Exchange of Global Notes. A Global Note may not be
transferred as a whole except by the Depositary to a nominee of the Depositary,
by a nominee of the Depositary to the Depositary or to another nominee of the
Depositary, or by the Depositary or any such nominee to a successor Depositary
or a nominee of such successor Depositary. All Global Notes will be exchanged by
the Company for Definitive Notes if (i) the Company delivers to the Trustee
notice from the Depositary that the Depositary is unwilling or unable to
continue to act as Depositary or that the Depositary is no longer a clearing
agency registered under the Exchange Act and, in either case, a successor
Depositary is not appointed by the Company within 120 days after the date of
such notice from the Depositary, (ii) the Company in its sole discretion
determines that the Global Notes (in whole but not in part) should be exchanged
for Definitive Notes and delivers a written notice to such effect to the Trustee
or (iii) there has occurred and is occurring a Default or an Event of Default
with respect to the Notes; provided that in no event shall the Regulation S
Temporary Global Note be exchanged by the Company for Definitive Notes prior to
(x) the expiration of the Restricted Period and (y) the receipt by the Registrar
of any certificates required pursuant to Rule 903(b)(3)(ii)(B) under the
Securities Act. Upon the occurrence of either of the preceding events in (i) or
(ii) above, Definitive Notes shall be issued in such names as the Depositary
shall instruct the Trustee. Global Notes also may be exchanged or replaced, in
whole or in part, as provided in Sections 2.07 and 2.10 hereof. Every Note
authenticated and delivered in exchange for, or in

                                       21

<PAGE>

lieu of, a Global Note or any portion thereof, pursuant to this Section 2.06 or
Section 2.07 or 2.10 hereof, shall be authenticated and delivered in the form
of, and shall be, a Global Note. A Global Note may not be exchanged for another
Note other than as provided in this Section 2.06(a); however, beneficial
interests in a Global Note may be transferred and exchanged as provided in
Section 2.06(b), (c) or (f) hereof.

        (b)     Transfer and Exchange of Beneficial Interests in the Global
Notes. The transfer and exchange of beneficial interests in the Global Notes
shall be effected through the Depositary, in accordance with the provisions of
this Indenture and the Applicable Procedures. Beneficial interests in the
Restricted Global Notes shall be subject to restrictions on transfer comparable
to those set forth herein to the extent required by the Securities Act.
Transfers of beneficial interests in the Global Notes also shall require
compliance with either subparagraph (i) or (ii) below, as applicable, as well as
one or more of the other following subparagraphs, as applicable:

                (i)     Transfer of Beneficial Interests in the Same Global
        Note. Beneficial interests in any Restricted Global Note may be
        transferred to Persons who take delivery thereof in the form of a
        beneficial interest in the same Restricted Global Note in accordance
        with the transfer restrictions set forth in the Private Placement
        Legend; provided, however, that prior to the expiration of the
        Restricted Period, transfers of beneficial interests in the Temporary
        Regulation S Global Note may not be made to a U.S. Person or for the
        account or benefit of a U.S. Person (other than the Initial Purchasers).
        Beneficial interests in any Unrestricted Global Note may be transferred
        to Persons who take delivery thereof in the form of a beneficial
        interest in an Unrestricted Global Note. No written orders or
        instructions shall be required to be delivered to the Registrar to
        effect the transfers described in this Section 2.06(b)(i).

                (ii)    All Other Transfers and Exchanges of Beneficial
        Interests in Global Notes. In connection with all transfers and
        exchanges of beneficial interests that are not subject to Section
        2.06(b)(i) above, the transferor of such beneficial interest must
        deliver to the Registrar either (A) (1) a written order from a
        Participant or an Indirect Participant given to the Depositary in
        accordance with the Applicable Procedures directing the Depositary to
        credit or cause to be credited a beneficial interest in another Global
        Note in an amount equal to the beneficial interest to be transferred or
        exchanged and (2) instructions given in accordance with the Applicable
        Procedures containing information regarding the Participant account to
        be credited with such increase or (B) (1) a written order from a
        Participant or an Indirect Participant given to the Depositary in
        accordance with the Applicable Procedures directing the Depositary to
        cause to be issued a Definitive Note in an amount equal to the
        beneficial interest to be transferred or exchanged and (2) instructions
        given by the Depositary to the Registrar containing information
        regarding the Person in whose name such Definitive Note shall be
        registered to effect the transfer or exchange referred to in (1) above;
        provided that in no event shall Definitive Notes be issued upon the
        transfer or exchange of beneficial interests in the Regulation S
        Temporary Global Note prior to (x) the expiration of the Restricted
        Period and (y) the receipt by the Registrar of any certificates required
        pursuant to Rule 903. Upon consummation of an Exchange Offer by the
        Company in accordance with Section 2.06(f) hereof, the requirements of
        this Section 2.06(b)(ii) shall be deemed to have been satisfied upon
        receipt by the Registrar of the instructions contained in the Letter of
        Transmittal delivered by the Holder of such beneficial interests in the
        Restricted Global Notes. Upon satisfaction of all of the requirements
        for transfer or exchange of beneficial interests in Global Notes
        contained in this Indenture and the Notes or otherwise applicable under
        the Securities Act, the Trustee shall adjust the principal amount of the
        relevant Global Note(s) pursuant to Section 2.06(h) hereof.

                                       22

<PAGE>

                (iii)   Transfer of Beneficial Interests to Another Restricted
        Global Note. A beneficial interest in any Restricted Global Note may be
        transferred to a Person who takes delivery thereof in the form of a
        beneficial interest in another Restricted Global Note if the transfer
        complies with the requirements of Section 2.06(b)(ii) above and the
        Registrar receives the following:

                        (A)     if the transferee will take delivery in the form
                of a beneficial interest in the 144A Global Note, then the
                transferor must deliver a certificate in the form of Exhibit B
                hereto, including the certifications in item (1) thereof;

                        (B)     if the transferee will take delivery in the form
                of a beneficial interest in the Regulation S Temporary Global
                Note or the Regulation S Global Note, then the transferor must
                deliver a certificate in the form of Exhibit B hereto, including
                the certifications in item (2) thereof; and

                        (C)     if the transferee is an Institutional Accredited
                Investor who will take delivery in the form of a beneficial
                interest in the 144A Global Note, then the transferor must
                deliver a certificate in the form of Exhibit B hereto, including
                the certifications and certificates and Opinion of Counsel
                required by item (3) thereof, if applicable.

                (iv)    Transfer and Exchange of Beneficial Interests in a
        Restricted Global Note for Beneficial Interests in the Unrestricted
        Global Note. A beneficial interest in any Restricted Global Note may be
        exchanged by any holder thereof for a beneficial interest in an
        Unrestricted Global Note or transferred to a Person who takes delivery
        thereof in the form of a beneficial interest in an Unrestricted Global
        Note if the exchange or transfer complies with the requirements of
        Section 2.06(b)(ii) above and:

                        (A)     such exchange or transfer is effected pursuant
                to the Exchange Offer in accordance with the Registration Rights
                Agreement and the holder of the beneficial interest to be
                transferred, in the case of an exchange, or the transferee, in
                the case of a transfer, certifies in the applicable Letter of
                Transmittal that it is not (1) a broker-dealer, (2) a Person
                participating in the distribution of the Exchange Notes or (3) a
                Person who is an Affiliate of the Company;

                        (B)     such transfer is effected pursuant to the Shelf
                Registration Statement in accordance with the Registration
                Rights Agreement;

                        (C)     such transfer is effected by a Broker-Dealer
                pursuant to the Exchange Offer Registration Statement in
                accordance with the Registration Rights Agreement; or

                        (D)     the Registrar receives the following:

                                (1)     if the holder of such beneficial
                        interest in a Restricted Global Note proposes to
                        exchange such beneficial interest for a beneficial
                        interest in an Unrestricted Global Note, a certificate
                        from such holder in the form of Exhibit C hereto,
                        including the certifications in item (1)(a) thereof; or

                                (2)     if the holder of such beneficial
                        interest in a Restricted Global Note proposes to
                        transfer such beneficial interest to a Person who shall
                        take delivery thereof in the form of a beneficial
                        interest in an Unrestricted Global Note, a certificate
                        from such holder in the form of Exhibit B hereto,
                        including the certifications in item (4) thereof;

                                       23

<PAGE>

                        and, in each such case set forth in this subparagraph
                        (D), if the Registrar so requests or if the Applicable
                        Procedures so require, an Opinion of Counsel in form
                        reasonably acceptable to the Registrar to the effect
                        that such exchange or transfer is in compliance with the
                        Securities Act and that the restrictions on transfer
                        contained herein and in the Private Placement Legend are
                        no longer required in order to maintain compliance with
                        the Securities Act.

        If any such transfer is effected pursuant to subparagraph (B) or (D)
above at a time when an Unrestricted Global Note has not yet been issued, the
Company shall issue and, upon receipt of an Authentication Order in accordance
with Section 2.02 hereof, the Trustee shall authenticate one or more
Unrestricted Global Notes in an aggregate principal amount equal to the
aggregate principal amount of beneficial interests transferred pursuant to
subparagraph (B) or (D) above.

        Beneficial interests in an Unrestricted Global Note cannot be exchanged
for, or transferred to Persons who take delivery thereof in the form of, a
beneficial interest in a Restricted Global Note.

        (c)     Transfer or Exchange of Beneficial Interests for Definitive
Notes.

                (i)     Beneficial Interests in Restricted Global Notes to
        Restricted Definitive Notes. If any holder of a beneficial interest in a
        Restricted Global Note proposes to exchange such beneficial interest for
        a Restricted Definitive Note or to transfer such beneficial interest to
        a Person who takes delivery thereof in the form of a Restricted
        Definitive Note, then, upon receipt by the Registrar of the following
        documentation:

                        (A)     if the holder of such beneficial interest in a
                Restricted Global Note proposes to exchange such beneficial
                interest for a Restricted Definitive Note, a certificate from
                such holder in the form of Exhibit C hereto, including the
                certifications in item (2)(a) thereof;

                        (B)     if such beneficial interest is being transferred
                to a QIB in accordance with Rule 144A, a certificate to the
                effect set forth in Exhibit B hereto, including the
                certifications in item (1) thereof;

                        (C)     if such beneficial interest is being transferred
                to a Non-U.S. Person in an offshore transaction in accordance
                with Rule 903 or Rule 904, a certificate to the effect set forth
                in Exhibit B hereto, including the certifications in item (2)
                thereof;

                        (D)     if such beneficial interest is being transferred
                pursuant to an exemption from the registration requirements of
                the Securities Act in accordance with Rule 144, a certificate to
                the effect set forth in Exhibit B hereto, including the
                certifications in item (3)(a) thereof;

                        (E)     if such beneficial interest is being transferred
                to an Institutional Accredited Investor in reliance on an
                exemption from the registration requirements of the Securities
                Act other than those listed in subparagraphs (B) through (D)
                above, a certificate to the effect set forth in Exhibit B
                hereto, including the certifications, certificates and Opinion
                of Counsel required by item (3) thereof, if applicable;

                        (F)     if such beneficial interest is being transferred
                to the Company or any of its Subsidiaries, a certificate to the
                effect set forth in Exhibit B hereto, including the
                certifications in item (3)(b) thereof; or

                                       24

<PAGE>

                        (G)     if such beneficial interest is being transferred
                pursuant to an effective registration statement under the
                Securities Act, a certificate to the effect set forth in Exhibit
                B hereto, including the certifications in item (3)(c) thereof,

        the Trustee shall cause the aggregate principal amount of the applicable
        Global Note to be reduced accordingly pursuant to Section 2.06(h)
        hereof, and the Company shall execute and the Trustee shall authenticate
        and deliver to the Person designated in the instructions a Definitive
        Note in the appropriate principal amount. Any Definitive Note issued in
        exchange for a beneficial interest in a Restricted Global Note pursuant
        to this Section 2.06(c) shall be registered in such name or names and in
        such authorized denomination or denominations as the holder of such
        beneficial interest shall instruct the Registrar through instructions
        from the Depositary and the Participant or Indirect Participant. The
        Trustee shall deliver such Definitive Notes to the Persons in whose
        names such Notes are so registered. Any Definitive Note issued in
        exchange for a beneficial interest in a Restricted Global Note pursuant
        to this Section 2.06(c)(i) shall bear the Private Placement Legend and
        shall be subject to all restrictions on transfer contained therein.

                (ii)    Beneficial Interests in Regulation S Temporary Global
        Note to Definitive Notes. Notwithstanding Sections 2.06(c)(i)(A) and (C)
        hereof, a beneficial interest in the Regulation S Temporary Global Note
        may not be exchanged for a Definitive Note or transferred to a Person
        who takes delivery thereof in the form of a Definitive Note prior to (x)
        the expiration of the Restricted Period and (y) the receipt by the
        Registrar of any certificates required pursuant to Rule 903(b)(3)(ii)(B)
        under the Securities Act, except in the case of a transfer pursuant to
        an exemption from the registration requirements of the Securities Act
        other than Rule 903 or Rule 904.

                (iii)   Beneficial Interests in Restricted Global Notes to
        Unrestricted Definitive Notes. A holder of a beneficial interest in a
        Restricted Global Note may exchange such beneficial interest for an
        Unrestricted Definitive Note or may transfer such beneficial interest to
        a Person who takes delivery thereof in the form of an Unrestricted
        Definitive Note only if:

                        (A)     such exchange or transfer is effected pursuant
                to the Exchange Offer in accordance with the Registration Rights
                Agreement and the holder of such beneficial interest, in the
                case of an exchange, or the transferee, in the case of a
                transfer, certifies in the applicable Letter of Transmittal that
                it is not (1) a broker-dealer, (2) a Person participating in the
                distribution of the Exchange Notes or (3) a Person who is an
                Affiliate of the Company;

                        (B)     such transfer is effected pursuant to the Shelf
                Registration Statement in accordance with the Registration
                Rights Agreement;

                        (C)     such transfer is effected by a Broker-Dealer
                pursuant to the Exchange Offer Registration Statement in
                accordance with the Registration Rights Agreement; or

                        (D)     the Registrar receives the following:

                                (1)     if the holder of such beneficial
                        interest in a Restricted Global Note proposes to
                        exchange such beneficial interest for a Definitive Note
                        that does not bear the Private Placement Legend, a
                        certificate from such holder in the form of Exhibit C
                        hereto, including the certifications in item (1)(b)
                        thereof; or

                                       25

<PAGE>

                                (2)     if the holder of such beneficial
                        interest in a Restricted Global Note proposes to
                        transfer such beneficial interest to a Person who shall
                        take delivery thereof in the form of a Definitive Note
                        that does not bear the Private Placement Legend, a
                        certificate from such holder in the form of Exhibit B
                        hereto, including the certifications in item (4)
                        thereof;

        and, in each such case set forth in this subparagraph (D), if the
        Registrar so requests or if the Applicable Procedures so require, an
        Opinion of Counsel in form reasonably acceptable to the Registrar to the
        effect that such exchange or transfer is in compliance with the
        Securities Act and that the restrictions on transfer contained herein
        and in the Private Placement Legend are no longer required in order to
        maintain compliance with the Securities Act.

                (iv)    Beneficial Interests in Unrestricted Global Notes to
        Unrestricted Definitive Notes. If any holder of a beneficial interest in
        an Unrestricted Global Note proposes to exchange such beneficial
        interest for a Definitive Note or to transfer such beneficial interest
        to a Person who takes delivery thereof in the form of a Definitive Note,
        then, upon satisfaction of the conditions set forth in Section
        2.06(b)(iii) hereof, the Trustee shall cause the aggregate principal
        amount of the applicable Global Note to be reduced accordingly pursuant
        to Section 2.06(h) hereof, and the Company shall execute and the Trustee
        shall authenticate and deliver to the Person designated in the
        instructions a Definitive Note in the appropriate principal amount. Any
        Definitive Note issued in exchange for a beneficial interest pursuant to
        this Section 2.06(c)(iv) shall be registered in such name or names and
        in such authorized denomination or denominations as the holder of such
        beneficial interest shall instruct the Registrar through instructions
        from the Depositary and the Participant or Indirect Participant. The
        Trustee shall deliver such Definitive Notes to the Persons in whose
        names such Notes are so registered. Any Definitive Note issued in
        exchange for a beneficial interest pursuant to this Section 2.06(c)(iv)
        shall not bear the Private Placement Legend.

        (d)     Transfer and Exchange of Definitive Notes for Beneficial
Interests.

                (i)     Restricted Definitive Notes to Beneficial Interests in
        Restricted Global Notes. If any Holder of a Restricted Definitive Note
        proposes to exchange such Note for a beneficial interest in a Restricted
        Global Note or to transfer such Restricted Definitive Notes to a Person
        who takes delivery thereof in the form of a beneficial interest in a
        Restricted Global Note, then, upon receipt by the Registrar of the
        following documentation:

                        (A)     if the Holder of such Restricted Definitive Note
                proposes to exchange such Note for a beneficial interest in a
                Restricted Global Note, a certificate from such Holder in the
                form of Exhibit C hereto, including the certifications in item
                (2)(b) thereof;

                        (B)     if such Restricted Definitive Note is being
                transferred to a QIB in accordance with Rule 144A, a certificate
                to the effect set forth in Exhibit B hereto, including the
                certifications in item (1) thereof;

                        (C)     if such Restricted Definitive Note is being
                transferred to a Non-U.S. Person in an offshore transaction in
                accordance with Rule 903 or Rule 904, a certificate to the
                effect set forth in Exhibit B hereto, including the
                certifications in item (2) thereof;

                        (D)     if such Restricted Definitive Note is being
                transferred pursuant to an exemption from the registration
                requirements of the Securities Act in accordance with

                                       26

<PAGE>

                Rule 144, a certificate to the effect set forth in Exhibit B
                hereto, including the certifications in item (3)(a) thereof;

                        (E)     if such Restricted Definitive Note is being
                transferred to an Institutional Accredited Investor in reliance
                on an exemption from the registration requirements of the
                Securities Act other than those listed in subparagraphs (B)
                through (D) above, a certificate to the effect set forth in
                Exhibit B hereto, including the certifications, certificates and
                Opinion of Counsel required by item (3) thereof, if applicable;

                        (F)     if such Restricted Definitive Note is being
                transferred to the Company or any of its Subsidiaries, a
                certificate to the effect set forth in Exhibit B hereto,
                including the certifications in item (3)(b) thereof; or

                        (G)     if such Restricted Definitive Note is being
                transferred pursuant to an effective registration statement
                under the Securities Act, a certificate to the effect set forth
                in Exhibit B hereto, including the certifications in item (3)(c)
                thereof,

        the Trustee shall cancel the Restricted Definitive Note, increase or
        cause to be increased the aggregate principal amount of, in the case of
        clause (A) above, the appropriate Restricted Global Note, in the case of
        clause (C) above, the Regulation S Global Note, and in all other cases,
        the 144A Global Note.

                (ii)    Restricted Definitive Notes to Beneficial Interests in
        Unrestricted Global Notes. A Holder of a Restricted Definitive Note may
        exchange such Note for a beneficial interest in an Unrestricted Global
        Note or transfer such Restricted Definitive Note to a Person who takes
        delivery thereof in the form of a beneficial interest in an Unrestricted
        Global Note only if:

                        (A)     such exchange or transfer is effected pursuant
                to the Exchange Offer in accordance with the Registration Rights
                Agreement and the Holder, in the case of an exchange, or the
                transferee, in the case of a transfer, certifies in the
                applicable Letter of Transmittal that it is not (1) a
                Broker-Dealer, (2) a Person participating in the distribution
                of the Exchange Notes or (3) a Person who is an Affiliate of the
                Company;

                        (B)     such transfer is effected pursuant to the Shelf
                Registration Statement in accordance with the Registration
                Rights Agreement;

                        (C)     such transfer is effected by a Broker-Dealer
                pursuant to the Exchange Offer Registration Statement in
                accordance with the Registration Rights Agreement; or

                        (D)     the Registrar receives the following:

                                (1)     if the Holder of such Definitive Note
                        proposes to exchange such Note for a beneficial interest
                        in the Unrestricted Global Note, a certificate from such
                        Holder in the form of Exhibit C hereto, including the
                        certifications in item (1)(c) thereof; or

                                (2)     if the Holder of such Definitive Note
                        proposes to transfer such Note to a Person who shall
                        take delivery thereof in the form of a beneficial
                        interest in the Unrestricted Global Note, a certificate
                        from such Holder in the form of Exhibit B hereto,
                        including the certifications in item (4) thereof;

                                       27

<PAGE>

                and, in each such case set forth in this subparagraph (D), if
                the Registrar so requests or if the Applicable Procedures so
                require, an Opinion of Counsel in form reasonably acceptable to
                the Registrar to the effect that such exchange or transfer is in
                compliance with the Securities Act and that the restrictions on
                transfer contained herein and in the Private Placement Legend
                are no longer required in order to maintain compliance with the
                Securities Act.

                Upon satisfaction of the conditions of any of the subparagraphs
        in this Section 2.06(d)(ii), the Trustee shall cancel the Definitive
        Notes and increase or cause to be increased the aggregate principal
        amount of the Unrestricted Global Note.

                (iii)   Unrestricted Definitive Notes to Beneficial Interests in
        Unrestricted Global Notes. A Holder of an Unrestricted Definitive Note
        may exchange such Note for a beneficial interest in an Unrestricted
        Global Note or transfer such Definitive Note to a Person who takes
        delivery thereof in the form of a beneficial interest in an Unrestricted
        Global Note at any time. Upon receipt of a request for such an exchange
        or transfer, the Trustee shall cancel the applicable Unrestricted
        Definitive Note and increase or cause to be increased the aggregate
        principal amount of one of the Unrestricted Global Notes.

                If any such exchange or transfer from a Definitive Note to a
        beneficial interest is effected pursuant to subparagraphs (ii)(B),
        (ii)(D) or (iii) above at a time when an Unrestricted Global Note has
        not yet been issued, the Company shall issue and, upon receipt of an
        Authentication Order in accordance with Section 2.02 hereof, the Trustee
        shall authenticate one or more Unrestricted Global Notes in an aggregate
        principal amount equal to the principal amount of Definitive Notes so
        transferred.

        (e)     Transfer and Exchange of Definitive Notes for Definitive Notes.
Upon request by a Holder of Definitive Notes and such Holder's compliance with
the provisions of this Section 2.06(e), the Registrar shall register the
transfer or exchange of Definitive Notes. Prior to such registration of transfer
or exchange, the requesting Holder shall present or surrender to the Registrar
the Definitive Notes duly endorsed or accompanied by a written instruction of
transfer in form satisfactory to the Registrar duly executed by such Holder or
by its attorney, duly authorized in writing. In addition, the requesting Holder
shall provide any additional certifications, documents and information, as
applicable, required pursuant to the following provisions of this Section
2.06(e).

                (i)     Restricted Definitive Notes to Restricted Definitive
        Notes. Any Restricted Definitive Note may be transferred to and
        registered in the name of Persons who take delivery thereof in the form
        of a Restricted Definitive Note if the Registrar receives the following:

                        (A)     if the transfer will be made pursuant to Rule
                144A under the Securities Act, then the transferor must deliver
                a certificate in the form of Exhibit B hereto, including the
                certifications in item (1) thereof;

                        (B)     if the transfer will be made pursuant to Rule
                903 or Rule 904, then the transferor must deliver a certificate
                in the form of Exhibit B hereto, including the certifications in
                item (2) thereof; and

                        (C)     if the transfer will be made pursuant to any
                other exemption from the registration requirements of the
                Securities Act, then the transferor must deliver a certificate
                in the form of Exhibit B hereto, including the certifications,
                certificates and Opinion of Counsel required by item (3)
                thereof, if applicable.

                                       28

<PAGE>

                (ii)    Restricted Definitive Notes to Unrestricted Definitive
        Notes. Any Restricted Definitive Note may be exchanged by the Holder
        thereof for an Unrestricted Definitive Note or transferred to a Person
        or Persons who take delivery thereof in the form of an Unrestricted
        Definitive Note if:

                        (A)     such exchange or transfer is effected pursuant
                to the Exchange Offer in accordance with the Registration Rights
                Agreement and the Holder, in the case of an exchange, or the
                transferee, in the case of a transfer, certifies in the
                applicable Letter of Transmittal that it is not (1) a
                Broker-Dealer, (2) a Person participating in the distribution of
                the Exchange Notes or (3) a Person who is an Affiliate of the
                Company;

                        (B)     any such transfer is effected pursuant to the
                Shelf Registration Statement in accordance with the Registration
                Rights Agreement;

                        (C)     any such transfer is effected by a Broker-Dealer
                pursuant to the Exchange Offer Registration Statement in
                accordance with the Registration Rights Agreement; or

                        (D)     the Registrar receives the following:

                                (1)     if the Holder of such Restricted
                        Definitive Notes proposes to exchange such Notes for an
                        Unrestricted Definitive Note, a certificate from such
                        Holder in the form of Exhibit C hereto, including the
                        certifications in item (1)(d) thereof; or

                                (2)     if the Holder of such Restricted
                        Definitive Notes proposes to transfer such Notes to a
                        Person who shall take delivery thereof in the form of an
                        Unrestricted Definitive Note, a certificate from such
                        Holder in the form of Exhibit B hereto, including the
                        certifications in item (4) thereof;

                and, in each such case set forth in this subparagraph (D), if
                the Registrar so requests, an Opinion of Counsel in form
                reasonably acceptable to the Company to the effect that such
                exchange or transfer is in compliance with the Securities Act
                and that the restrictions on transfer contained herein and in
                the Private Placement Legend are no longer required in order to
                maintain compliance with the Securities Act.

                (iii)   Unrestricted Definitive Notes to Unrestricted Definitive
        Notes. A Holder of Unrestricted Definitive Notes may transfer such Notes
        to a Person who takes delivery thereof in the form of an Unrestricted
        Definitive Note. Upon receipt of a request to register such a transfer,
        the Registrar shall register the Unrestricted Definitive Notes pursuant
        to the instructions from the Holder thereof.

        (f)     Exchange Offer. Upon the occurrence of the Exchange Offer in
accordance with the Registration Rights Agreement, the Company shall issue and,
upon receipt of an Authentication Order in accordance with Section 2.02, the
Trustee shall authenticate (i) one or more Unrestricted Global Notes in an
aggregate principal amount equal to the principal amount of the beneficial
interests in the Restricted Global Notes tendered for acceptance by Persons that
certify in the applicable Letters of Transmittal that (x) they are not
Broker-Dealers, (y) they are not participating in a distribution of the
Exchange Notes and (z) they are not Affiliates of the Company, and accepted for
exchange in the Exchange Offer and (ii) Definitive Notes in an aggregate
principal amount equal to the principal amount of the Restricted Definitive
Notes accepted for exchange in the Exchange Offer. Concurrently with the
issuance of such

                                       29

<PAGE>

Notes, the Trustee shall cause the aggregate principal amount of the applicable
Restricted Global Notes to be reduced accordingly, and the Company shall
execute, and the Trustee shall authenticate and deliver to the Persons
designated by the Holders of Definitive Notes so accepted, Definitive Notes in
the appropriate principal amount.

        (g)     Legends. The following legends shall appear on the face of all
Global Notes and Definitive Notes issued under this Indenture unless
specifically stated otherwise in the applicable provisions of this Indenture.

                (i)     Private Placement Legend.

                        (A)     Except as permitted by subparagraph (B) below,
                each Global Note and each Definitive Note (and all Notes issued
                in exchange therefor or substitution thereof) shall bear the
                legend in substantially the following form:

"THE SECURITY (OR ITS PREDECESSOR) EVIDENCED HEREBY WAS ORIGINALLY ISSUED IN A
TRANSACTION EXEMPT FROM REGISTRATION UNDER SECTION 5 OF THE UNITED STATES
SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), AND THE SECURITY
EVIDENCED HEREBY MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED IN THE
ABSENCE OF SUCH REGISTRATION OR AN APPLICABLE EXEMPTION THEREFROM. EACH
PURCHASER OF THE SECURITY EVIDENCED HEREBY IS HEREBY NOTIFIED THAT THE SELLER
MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE
SECURITIES ACT PROVIDED BY RULE 144A THEREUNDER. THE HOLDER OF THE SECURITY
EVIDENCED HEREBY AGREES FOR THE BENEFIT OF THE ISSUER THAT (A) SUCH SECURITY MAY
BE RESOLD, PLEDGED OR OTHERWISE TRANSFERRED ONLY (1) (a) IN THE UNITED STATES TO
A PERSON WHO THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER
(AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT) IN A TRANSACTION MEETING THE
REQUIREMENTS OF RULE 144A, (b) OUTSIDE THE UNITED STATES IN AN OFFSHORE
TRANSACTION IN ACCORDANCE WITH RULE 904 UNDER THE SECURITIES ACT, (c) IN A
TRANSACTION MEETING THE REQUIREMENTS OF RULE 144 UNDER THE SECURITIES ACT, (d)
TO AN INSTITUTIONAL "ACCREDITED INVESTOR" (AS DEFINED IN RULE 501 (a) (1), (2),
(3) OR (7) OF THE SECURITIES ACT (AN "INSTITUTIONAL ACCREDITED INVESTOR")) THAT,
PRIOR TO SUCH TRANSFER, FURNISHES THE TRUSTEE A SIGNED LETTER CONTAINING CERTAIN
REPRESENTATIONS AND AGREEMENTS (THE FORM OF WHICH CAN BE OBTAINED FROM THE
TRUSTEE) AND, IF SUCH TRANSFER IS IN RESPECT OF AN AGGREGATE PRINCIPAL AMOUNT OF
NOTES LESS THAN $250,000, AN OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY THAT
SUCH TRANSFER IS IN COMPLIANCE WITH THE SECURITIES ACT OR (e) IN ACCORDANCE WITH
ANOTHER EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT (AND
BASED UPON AN OPINION OF COUNSEL IF THE COMPANY SO REQUESTS), (2) TO THE COMPANY
OR (3) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT AND, IN EACH CASE, IN
ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES
OR ANY OTHER APPLICABLE JURISDICTION AND (B) THE HOLDER WILL, AND EACH
SUBSEQUENT HOLDER IS REQUIRED TO, NOTIFY ANY PURCHASER FROM IT OF THE SECURITY
EVIDENCED HEREBY OF THE RESALE RESTRICTIONS SET FORTH IN (A) ABOVE."

                        (B)     Notwithstanding the foregoing, any Global Note
                or Definitive Note issued pursuant to subparagraphs (b)(iv),
                (c)(iii), (c)(iv), (d)(ii), (d)(iii), (e)(ii), (e)(iii) or

                                       30

<PAGE>

                (f) of this Section 2.06 (and all Notes issued in exchange
                therefor or substitution thereof) shall not bear the Private
                Placement Legend.

                (ii)    Global Note Legend. Each Global Note shall bear a legend
        in substantially the following form:

"THIS GLOBAL NOTE IS HELD BY THE DEPOSITARY (AS DEFINED IN THE INDENTURE
GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE BENEFICIAL
OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY CIRCUMSTANCES
EXCEPT THAT (I) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS MAY BE REQUIRED
PURSUANT TO SECTION 2.06 OF THE INDENTURE, (II) THIS GLOBAL NOTE MAY BE
EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 2.06 OF THE INDENTURE,
(III) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE FOR CANCELLATION PURSUANT
TO SECTION 2.11 OF THE INDENTURE AND (IV) THIS GLOBAL NOTE MAY BE TRANSFERRED TO
A SUCCESSOR DEPOSITARY WITH THE PRIOR WRITTEN CONSENT OF THE COMPANY."

                (iii)   Regulation S Temporary Global Note Legend. The
        Regulation S Temporary Global Note shall bear a legend in substantially
        the following form:

"THE RIGHTS ATTACHING TO THIS REGULATION S TEMPORARY GLOBAL NOTE, AND THE
CONDITIONS AND PROCEDURES GOVERNING ITS EXCHANGE FOR CERTIFICATED NOTES, ARE AS
SPECIFIED IN THE INDENTURE (AS DEFINED HEREIN). NEITHER THE HOLDER NOR THE
BENEFICIAL OWNERS OF THIS REGULATION S TEMPORARY GLOBAL NOTE SHALL BE ENTITLED
TO RECEIVE PAYMENT OF INTEREST HEREON OR LIQUIDATED DAMAGES PRIOR TO THE
EXCHANGE OF THIS NOTE FOR A REGULATION S PERMANENT GLOBAL NOTE AS CONTEMPLATED
BY THE INDENTURE."

        (h)     Cancellation and/or Adjustment of Global Notes. At such time as
all beneficial interests in a particular Global Note have been exchanged for
Definitive Notes or a particular Global Note has been redeemed, repurchased or
canceled in whole and not in part, each such Global Note shall be returned to or
retained and canceled by the Trustee in accordance with Section 2.11 hereof. At
any time prior to such cancellation, if any beneficial interest in a Global Note
is exchanged for or transferred to a Person who will take delivery thereof in
the form of a beneficial interest in another Global Note or for Definitive
Notes, the principal amount of Notes represented by such Global Note shall be
reduced accordingly and an endorsement shall be made on such Global Note by the
Trustee or by the Depositary at the direction of the Trustee to reflect such
reduction; and if the beneficial interest is being exchanged for or transferred
to a Person who will take delivery thereof in the form of a beneficial interest
in another Global Note, such other Global Note shall be increased accordingly
and an endorsement shall be made on such Global Note by the Trustee or by the
Depository at the direction of the Trustee to reflect such increase.

        (i)     General Provisions Relating to Transfers and Exchanges.

                (i)     To permit registrations of transfers and exchanges, the
        Company shall execute, and the Trustee shall authenticate, Global Notes
        and Definitive Notes upon the Company's order or at the Registrar's
        request.

                (ii)    No service charge shall be made to a holder of a
        beneficial interest in a Global Note or to a Holder of a Definitive Note
        for any registration of transfer or exchange, but the Company may
        require payment of a sum sufficient to cover any transfer tax or similar
        governmental charge payable in connection therewith (other than any such
        transfer taxes or

                                       31

<PAGE>

        similar governmental charge payable upon exchange or transfer pursuant
        to Sections 2.10, 3.06, 3.09, 4.10, 4.15, and 9.05 hereof).

                (iii)   The Registrar shall not be required to register the
        transfer of or exchange any Note selected for redemption in whole or in
        part, except the unredeemed portion of any Note being redeemed in part.

                (iv)    All Global Notes and Definitive Notes issued upon any
        registration of transfer or exchange of Global Notes or Definitive Notes
        shall be the valid obligations of the Company, evidencing the same debt,
        and entitled to the same benefits under this Indenture, as the Global
        Notes or Definitive Notes surrendered upon such registration of transfer
        or exchange.

                (v)     The Company shall not be required (A) to issue, to
        register the transfer of or to exchange any Notes during a period
        beginning at the opening of business 15 days before the day of any
        selection of Notes for redemption under Section 3.02 hereof and ending
        at the close of business on the day of selection, (B) to register the
        transfer of or to exchange any Note so selected for redemption in whole
        or in part, except the unredeemed portion of any Note being redeemed in
        part or (C) to register the transfer of or to exchange a Note between a
        record date and the next succeeding interest payment date.

                (vi)    Prior to due presentment for the registration of a
        transfer of any Note, the Trustee, any Agent and the Company may deem
        and treat the Person in whose name any Note is registered as the
        absolute owner of such Note for the purpose of receiving payment of
        principal of and interest on such Notes and for all other purposes, and
        none of the Trustee, any Agent or the Company shall be affected by
        notice to the contrary.

                (vii)   The Trustee shall authenticate Global Notes and
        Definitive Notes in accordance with the provisions of Section 2.02
        hereof.

                (viii)  All certifications, certificates and Opinions of Counsel
        required to be submitted to the Registrar pursuant to this Section 2.06
        to effect a registration of transfer or exchange may be submitted by
        facsimile.

Section 2.07    Replacement Notes.

        If any mutilated Note is surrendered to the Trustee or the Company, or
the Trustee receives evidence to its satisfaction of the destruction, loss or
theft of any Note, the Company shall issue and the Trustee, upon receipt of an
Authentication Order, shall authenticate a replacement Note if the Trustee's
requirements are met. If required by the Trustee or the Company, an indemnity
bond must be supplied by the Holder that is sufficient in the judgment of the
Trustee and the Company to protect the Company, the Trustee, any Agent and any
authenticating agent from any loss that any of them may suffer if a Note is
replaced. The Company may charge for its expenses in replacing a Note. If, after
the delivery of such replacement Note, a bona fide purchaser of the original
Note in lieu of which such replacement Note was issued presents for payment or
registration such original Note, the Trustee shall be entitled to recover such
replacement Note from the Person to whom it was delivered or any Person taking
therefrom, except a bona fide purchaser, and shall be entitled to recover upon
the security or indemnity provided therefor to the extent of any loss, damage,
cost or expense incurred by the Company, the Trustee, any Agent and any
authenticating agent in connection therewith.

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<PAGE>

        Subject to the provisions of the final sentence of the preceding
paragraph of this Section 2.07, every replacement Note is an additional
obligation of the Company and shall be entitled to all of the benefits of this
Indenture equally and proportionately with all other Notes duly issued
hereunder.

Section 2.08    Outstanding Notes.

        The Notes outstanding at any time are all the Notes authenticated by the
Trustee except for those canceled by it, those delivered to it for cancellation,
those reductions in the interest in a Global Note effected by the Trustee in
accordance with the provisions hereof, and those described in this Section as
not outstanding. Except as set forth in Section 2.09 hereof, a Note does not
cease to be outstanding because the Company, any Subsidiary of the Company or an
Affiliate of the Company holds the Note; however, Notes held by the Company or
any Affiliate of the Company shall not be deemed to be outstanding for purposes
of Section 3.07(b) hereof.

        If a Note is replaced pursuant to Section 2.07 hereof, it ceases to be
outstanding unless the Trustee receives proof satisfactory to it that the
replaced Note is held by a bona fide purchaser.

        If the entire principal of and premium, interest and Liquidated Damages,
if any, on any Note are considered paid under Section 4.01 hereof, it ceases to
be outstanding and interest and Liquidated Damages, if any, on it cease to
accrue.

        If the Paying Agent (other than the Company, a Subsidiary of the Company
or an Affiliate of the Company) holds, on a redemption date or maturity date,
money sufficient to pay Notes payable on that date, then on and after that date
such Notes shall be deemed to be no longer outstanding and shall cease to accrue
interest and Liquidated Damages, if any.

Section 2.09    Treasury Notes.

        In determining whether the Holders of the required principal amount of
Notes have concurred in any direction, waiver or consent, Notes owned by the
Company, Parent, a Subsidiary of the Company or an Affiliate of the Company
shall be considered as though not outstanding, except that for the purposes of
determining whether the Trustee shall be protected in relying on any such
direction, waiver or consent, only Notes that the Trustee knows are so owned
shall be so disregarded. Notwithstanding the foregoing, Notes that the Company,
Parent, a Subsidiary of the Company or an Affiliate of the Company offers to
purchase or acquires pursuant to an offer, exchange offer, tender offer or
otherwise shall not be deemed to be owned by the Company, Parent, a Subsidiary
of the Company or an Affiliate of the Company until legal title to such Notes
passes to the Company, Parent, such Subsidiary or such Affiliate as the case may
be.

Section 2.10    Temporary Notes.

        Until definitive Notes are ready for delivery, the Company may prepare
and the Trustee shall authenticate temporary Notes upon receipt on an
Authentication Order. Temporary Notes shall be substantially in the form of
definitive Notes but may have variations that the Company considers appropriate
for temporary Notes and as shall be reasonably acceptable to the Trustee.
Without unreasonable delay, the Company shall prepare and the Trustee shall
authenticate definitive Notes in exchange for temporary Notes. Until such
exchange, Holders of temporary Notes shall be entitled to all of the benefits of
this Indenture.

                                       33

<PAGE>

Section 2.11    Cancellation.

        The Company at any time may deliver Notes to the Trustee for
cancellation. The Registrar and Paying Agent shall forward to the Trustee any
Notes surrendered to them for registration of transfer, exchange or payment. The
Trustee and no one else shall cancel all Notes surrendered for registration of
transfer, exchange, payment, replacement or cancellation and, at the request of
the Company, shall destroy canceled Notes (subject to the record retention
requirement of the Exchange Act). Certification of the destruction of all
canceled Notes shall be delivered to the Company. The Company may not issue new
Notes to replace Notes that it has paid or that have been delivered to the
Trustee for cancellation, other than as contemplated by the Exchange Offer.

Section 2.12    Defaulted Interest.

        If the Company defaults in a payment of interest on the Notes, it shall
pay the defaulted interest in any lawful manner plus, to the extent lawful,
interest payable on the defaulted interest, to the Persons who are Holders on a
subsequent special record date, in each case at the rate provided in the Notes
and in Section 4.01 hereof. The Company shall notify the Trustee in writing of
the amount of defaulted interest proposed to be paid on each Note and the date
of the proposed payment. The Company shall fix or cause to be fixed each such
special record date and payment date, provided, however, that no such special
record date shall be less than 10 days prior to the related payment date for
such defaulted interest. At least 15 days before the special record date, the
Company (or, upon the written request of the Company, the Trustee in the name
and at the expense of the Company) shall mail or cause to be mailed to Holders a
notice that states the special record date, the related payment date and the
amount of such interest to be paid.

                                   ARTICLE 3.
                            REDEMPTION AND PREPAYMENT

Section 3.01    Notices to Trustee.

        If the Company elects to redeem Notes pursuant to the redemption
provisions of Section 3.07 or 3.08 hereof, it shall furnish to the Trustee, in
the case of a redemption pursuant to Section 3.07, at least 45 days but not more
than 60 days before such redemption date, and in the case of a redemption
pursuant to Section 3.08, at least 10 days but not more than 60 days before such
redemption date, an Officers' Certificate setting forth (i) the clause of this
Indenture pursuant to which the redemption shall occur, (ii) the redemption
date, (iii) the principal amount of Notes to be redeemed and (iv) the redemption
price.

Section 3.02    Selection of Notes to Be Redeemed or Purchased.

        If less than all of the Notes are to be redeemed or purchased in an
offer to purchase at any time, the Trustee shall select the Notes for redemption
or purchase as follows:

        (i)     if the Notes are listed on any national securities exchange, in
compliance with the requirements of the principal national securities exchange
on which the Notes are listed, or

        (ii)    if the Notes are not listed on any national securities exchange,
on a pro rata basis, by lot or in accordance with any other method the Trustee
considers fair and appropriate. In the event of partial redemption or purchase
by lot, the particular Notes to be redeemed or purchased shall be selected,
unless otherwise provided herein, not less than 30 days nor more than 60 days
prior to the redemption or purchase date by the Trustee from the outstanding
Notes not previously called for redemption or purchase.

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<PAGE>

        The Trustee shall promptly notify the Company in writing of the Notes
selected for redemption or purchase and, in the case of any Note selected for
partial redemption or purchase, the principal amount thereof to be redeemed or
purchased. Notes and portions of Notes selected shall be in amounts of $1,000 or
whole multiples of $1,000; except that if all of the Notes of a Holder are to be
redeemed or purchased, the entire outstanding about of Notes held by such
Holder, even if not a multiple of $1,000, shall be redeemed or purchased. Except
as provided in the preceding sentence, provisions of this Indenture that apply
to Notes called for redemption or purchase also apply to portions of Notes
called for redemption or purchase.

        The provisions of the two preceding paragraphs of this Section 3.02
shall not apply with respect to any redemption affecting only a Global Note,
whether such Global Note is to be redeemed in whole or in part. In case of any
such redemption in part, the unredeemed portion of the principal amount of the
Global Note shall be in an authorized denomination.

Section 3.03    Notice of Redemption.

        Subject to the provisions of Section 3.09 hereof, at least 30 days (or
such shorter period as may be acceptable to DTC in the case of a mandatory
redemption) but not more than 60 days before a redemption date, the Company
shall mail or cause to be mailed, by first class mail, a notice of redemption to
each Holder whose Notes are to be redeemed at its registered address; except
that redemption notices may be mailed more than 60 days prior to a redemption
date if the notice is issued in connection with a defeasance of the Notes or a
satisfaction and discharge of this Indenture pursuant to Article 8 or Article 11
of this Indenture.

        The notice shall identify the Notes to be redeemed and shall state:

        (a)     the redemption date;

        (b)     the redemption price;

        (c)     if any Note is being redeemed in part, the portion of the
principal amount of such Note to be redeemed and that, after the redemption date
upon surrender of such Note, a new Note or Notes in a principal amount equal to
the unredeemed portion shall be issued upon cancellation of the original Note;

        (d)     the name and address of the Paying Agent;

        (e)     that Notes called for redemption must be surrendered to the
Paying Agent to collect the redemption price;

        (f)     that, unless the Company defaults in making such redemption
payment, interest and Liquidated Damages, if any, on Notes called for redemption
cease to accrue on and after the redemption date;

        (g)     the paragraph of the Notes and/or Section of this Indenture
pursuant to which the Notes called for redemption are being redeemed; and

        (h)     that no representation is made as to the correctness or accuracy
of the CUSIP number, if any, listed in such notice or printed on the Notes.

                                       35

<PAGE>

        If any of the Notes to be redeemed is in the form of a Global Note, then
the Company shall modify such notice to the extent necessary to accord with the
procedures of the Depository applicable to redemption.

        At the Company's request, the Trustee shall give the notice of
redemption in the Company's name and at its expense; provided, however, that the
Company shall have delivered to the Trustee, at least 45 days (unless the
Company and the Trustee agree to a shorter period) prior to the redemption date,
an Officers' Certificate requesting that the Trustee give such notice and
setting forth the information to be stated in such notice as provided in the
preceding paragraph.

Section 3.04    Effect of Notice of Redemption.

        Once notice of redemption is mailed in accordance with Section 3.03
hereof, Notes called for redemption become irrevocably due and payable on the
redemption date at the redemption price. A notice of redemption may not be
conditional.

Section 3.05    Deposit of Redemption or Purchase Price.

        At least one Business Day prior to any optional redemption or purchase
date, the Company shall deposit with the Trustee or Paying Agent money
sufficient to pay the redemption or purchase price of and accrued interest and
Liquidated Damages, if any, on all Notes to be redeemed or purchased on that
date. Frontier Escrow Corporation shall deposit 101% of the aggregate principal
amount of the Notes, plus accrued interest on the Notes to, but not including,
October 31, 2003 with the Escrow Agent on the Issue Date in accordance with the
Escrow Agreement. The Trustee or Paying Agent shall promptly pay to the Company
any money deposited with the Trustee or Paying Agent in excess of the amounts
necessary to pay the redemption or purchase price of and accrued interest and
Liquidated Damages, if any, on all Notes to be redeemed or purchased.

        If the Company complies with the provisions of the preceding paragraph,
on and after the redemption or purchase date, interest and Liquidated Damages,
if any, shall cease to accrue on the Notes or the portions of Notes called for
redemption. If a Note is redeemed or purchased on or after an interest record
date but on or prior to the related interest payment date, then any accrued and
unpaid interest and Liquidated Damages, if any, shall be paid to the Person in
whose name such Note was registered at the close of business on such record
date. If any Note called for redemption or purchase shall not be so paid upon
surrender for redemption or purchase because of the failure of the Company to
comply with the preceding paragraph, interest shall be paid on the unpaid
principal, from the redemption or purchase date until such principal is paid,
and to the extent lawful on any interest and Liquidated Damages, if any, not
paid on such unpaid principal, in each case at the rate provided in the Notes
and in Section 4.01 hereof.

Section 3.06    Notes Redeemed or Purchased in Part.

        Upon surrender of a Note that is redeemed or purchased in part, the
Company shall issue, and upon receipt of an Authentication Order, the Trustee
shall authenticate for the Holder at the expense of the Company, a new Note
equal in principal amount to the unredeemed or unpurchased portion of the Note
surrendered.

Section 3.07    Optional Redemption.

        (a)     Except as set forth in clause (b) of this Section 3.07, the
Company shall not have the option to redeem the Notes pursuant to this Section
3.07 prior to April 15, 2008. Thereafter, the Company shall have the option to
redeem the Notes, in whole or in part, at the redemption prices

                                       36

<PAGE>

(expressed as percentages of principal amount) set forth below plus accrued and
unpaid interest and Liquidated Damages, if any, thereon, to the applicable
redemption date, if redeemed during the twelve-month period beginning on April
15 of the years indicated below:

           YEAR                             PERCENTAGE

           2008                              104.000%
           2009                              102.667%
           2010                              101.333%
           2011 and thereafter               100.000%

        (b)     Notwithstanding the provisions of clause (a) of this Section
3.07, (x) following the consummation of the Escrow Corp. Merger, the Company may
at any time prior to April 15, 2008, at its option, redeem the Notes, in whole
or in part, at the Make-Whole Price, plus accrued and unpaid interest and
Liquidated Damages, if any, thereon to the redemption date and (y) at any time
prior to April 15, 2006 and following the consummation of the Escrow Corp.
Merger, the Company may on any one or more occasions redeem up to 35% of the
aggregate principal amount of Notes issued under this Indenture at a redemption
price of 108.000% of the principal amount thereof, plus accrued and unpaid
interest and Liquidated Damages, if any, thereon to the redemption date, with
the net cash proceeds of one or more Equity Offerings (provided that, if the
Equity Offering is an offering by Parent, a portion of the Net Cash Proceeds
thereof equal to the amount required to redeem any such Notes is contributed to
the equity capital of the Company or used to acquire Capital Stock of the
Company (other than Disqualified Stock) from the Company); provided that (i) at
least 65% of the aggregate principal amount of Notes issued under this Indenture
remains outstanding immediately after the occurrence of each such redemption
pursuant to this clause (y) and (ii) each such redemption shall occur within 120
days of the date of the closing of each such Equity Offering.

        (c)     Any redemption pursuant to this Section 3.07 or Section 3.08(b)
shall be made pursuant to the provisions of Section 3.01 through Section 3.06
hereof.

Section 3.08    Special Mandatory Redemption.

        (a)     Except as set forth in clause (b) of this Section 3.08 or under
Sections 4.10 and 4.15 hereof, the Company shall not be required to make
mandatory redemption or sinking fund payments with respect to the Notes.

        (b)     In accordance with the terms and conditions of the Escrow
Agreement, and using the Deposit, the Company shall redeem all and not less than
all of the Offered Notes on October 31, 2003, or such earlier date as the
Company shall elect (the "Special Mandatory Redemption Date"), if the Escrow
Corp. Merger has not occurred on or prior to the Special Mandatory Redemption
Date, at a redemption price equal to 101% of the aggregate principal amount of
the Notes, plus accrued and unpaid interest thereon to, but not including,
October 31, 2003. Upon the closing of the Escrow Corp. Merger on or before the
Special Mandatory Redemption Date, the foregoing provisions of this Section
3.08(b) shall be null and void.

Section 3.09    Offer to Purchase by Application of Excess Proceeds.

        In the event that, pursuant to Section 4.10 hereof, the Company shall be
required to commence an offer to all Holders to purchase Notes (an "Asset Sale
Offer"), it shall follow the procedures specified below.

                                       37

<PAGE>

        The Asset Sale Offer shall remain open for a period of 20 Business Days
following its commencement and no longer, except to the extent that a longer
period is required by applicable law (the "Offer Period"). No later than five
Business Days after the termination of the Offer Period (the "Purchase Date"),
the Company shall purchase the principal amount of Notes required to be
purchased pursuant to Section 4.10 hereof (the "Offer Amount") or, if less than
the Offer Amount has been tendered, all Notes validly tendered in response to
the Asset Sale Offer. Payment for any Notes so purchased shall be made in the
same manner as interest payments are made.

        If the Purchase Date is on or after an interest record date and on or
before the related interest payment date, any accrued and unpaid interest and
Liquidated Damages, if any, shall be paid to the Person in whose name a Note is
registered at the close of business on such record date, and no additional
interest or Liquidated Damages, if any, shall be payable to Holders who tender
Notes pursuant to the Asset Sale Offer.

        Upon the commencement of an Asset Sale Offer, the Company shall send, by
first class mail, a notice to each of the Holders, with a copy to the Trustee.
The notice shall contain all instructions and materials necessary to enable such
Holders to tender Notes pursuant to the Asset Sale Offer. The Asset Sale Offer
shall be made to all Holders. The notice, which shall govern the terms of the
Asset Sale Offer, shall state:

        (a)     that the Asset Sale Offer is being made pursuant to this Section
3.09 and Section 4.10 hereof and the length of time the Asset Sale Offer shall
remain open;

        (b)     the Offer Amount, the purchase price and the Purchase Date;

        (c)     that any Note not tendered or accepted for payment shall
continue to accrue interest and Liquidated Damages, if any;

        (d)     that, unless the Company defaults in making such payment, any
Note accepted for payment pursuant to the Asset Sale Offer shall cease to accrue
interest and Liquidated Damages, if any, after the Purchase Date;

        (e)     that Holders electing to have a Note purchased pursuant to an
Asset Sale Offer may elect to have Notes purchased in integral multiples of
$1,000 only;

        (f)     that Holders electing to have a Note purchased pursuant to any
Asset Sale Offer shall be required to surrender the Note, with the form entitled
"Option of Holder to Elect Purchase" on the reverse of the Note completed, or
transfer by book-entry transfer, to the Company, a Depository, if appointed by
the Company, or a Paying Agent at the address specified in the notice at least
three days before the Purchase Date;

        (g)     that Holders shall be entitled to withdraw their election if the
Company, the Depository or the Paying Agent, as the case may be, receives, not
later than the expiration of the Offer Period, a telegram, telex, facsimile
transmission or letter setting forth the name of the Holder, the principal
amount of the Note the Holder delivered for purchase and a statement that such
Holder is withdrawing his election to have such Note purchased;

        (h)     that, if the aggregate principal amount of Notes surrendered by
Holders exceeds the Offer Amount, the Trustee shall select the Notes to be
purchased on a pro rata basis (with such adjustments as may be deemed
appropriate by the Trustee so that only Notes in denominations of $1,000, or
integral multiples thereof, shall be purchased); and

                                       38

<PAGE>

        (i)     that Holders whose Notes were purchased only in part shall be
issued new Notes equal in principal amount to the unpurchased portion of the
Notes surrendered (or transferred by book-entry transfer).

        If any of the Notes subject to an Asset Sale Offer is in the form of a
Global Note, then the Company shall modify such notice to the extent necessary
to accord with the procedures of the Depository applicable to repurchases.

        On or before the Purchase Date, the Company shall, to the extent lawful,
accept for payment, on a pro rata basis to the extent necessary, the Offer
Amount of Notes or portions thereof tendered pursuant to the Asset Sale Offer,
or if less than the Offer Amount has been tendered, all Notes tendered, and
shall deliver to the Trustee an Officers' Certificate stating that such Notes or
portions thereof were accepted for payment by the Company in accordance with the
terms of this Section 3.09. The Company or the Paying Agent, as the case may be,
shall promptly (but in any case not later than five days after the Purchase
Date) mail or deliver to each tendering Holder an amount equal to the purchase
price of the Notes tendered by such Holder and accepted by the Company for
purchase, and the Company shall promptly issue a new Note, and the Trustee shall
authenticate and mail or deliver such new Note to such Holder, in a principal
amount equal to any unpurchased portion of the Note surrendered. Any Note not so
accepted shall be promptly mailed or delivered by the Company to the Holder
thereof. The Company shall publicly announce the results of the Asset Sale Offer
on the Purchase Date.

        The Company shall comply with the requirements of Rule 14e-1 under the
Exchange Act and any other securities laws and regulations thereunder to the
extent such laws and regulations are applicable in connection with the
repurchase of Notes pursuant to an Asset Sale Offer. To the extent that the
provision of any securities laws or regulations conflict with this Section 3.09
and/or Section 4.10 hereof, the Company shall comply with the applicable
securities laws and regulations and shall not be deemed to have breached its
obligations under this Section 3.09 and/or Section 4.10 hereof by virtue of such
conflict.

        Other than as specifically provided in this Section 3.09, any purchase
pursuant to this Section 3.09 shall be made pursuant to the provisions of
Section 3.01 through Section 3.06 hereof.

                                   ARTICLE 4.
                                    COVENANTS

Section 4.01    Payment of Notes.

        The Company shall pay or cause to be paid the principal of and premium,
interest and Liquidated Damages, if any, on the Notes on the dates and in the
manner provided in the Notes. Principal, premium, interest and Liquidated
Damages, if any, shall be considered paid on the date due if the Paying Agent,
if other than the Company or a Subsidiary thereof, holds as of 10:00 a.m. New
York time on the due date money deposited by the Company in immediately
available funds and designated for and sufficient to pay all principal, premium,
and interest then due. The Company shall pay all Liquidated Damages, if any, in
the same manner on the dates and in the amounts set forth in the Registration
Rights Agreement.

        The Company shall, to the extent lawful, pay interest (including
post-petition interest in any proceeding under any Bankruptcy Law) on overdue
principal at the rate equal to the interest rate on the Notes; it shall, to the
extent lawful, pay interest (including post-petition interest in any proceeding
under any Bankruptcy Law) on overdue installments of interest and Liquidated
Damages, if any (without regard to any applicable grace period), at the same
rate.

                                       39

<PAGE>

Section 4.02    Maintenance of Office or Agency.

        The Company shall, in accordance with Section 2.03, maintain an office
or agency (which may be an office of the Trustee or an affiliate of the Trustee,
Registrar or co-registrar) in the Borough of Manhattan, the City and State of
New York, where Notes may be presented or surrendered for payment, where Notes
may be surrendered for registration of transfer or for exchange and where
notices and demands to or upon the Company in respect of the Notes and this
Indenture may be served. The Company shall give prompt written notice to the
Trustee of the location, and any change in the location, in accordance with
Section 2.03, of such office or agency. If at any time the Company shall fail to
maintain any such required office or agency or shall fail to furnish the Trustee
with the address thereof, such presentations, surrenders, notices and demands
may be made or served at the Corporate Trust Office of the Trustee.

        The Company may also from time to time designate one or more other
offices or agencies in the Borough of Manhattan, the City and State of New York,
where the Notes may be presented or surrendered for any or all such purposes and
may from time to time rescind such designations. Further, if at any time there
shall be no such office or agency in the Borough of Manhattan, the City and
State of New York, where the Notes may be presented or surrendered for payment,
the Company shall forthwith designate and maintain such an office or agency in
the Borough of Manhattan, the City and State of New York, in order that the
Notes shall at all times be payable in the Borough of Manhattan, the City and
State of New York. The Company shall give prompt written notice to the Trustee
of any such designation or rescission and of any change in the location of any
such other office or agency.

        The Company hereby designates the Corporate Trust Office of the Trustee
in the Borough of Manhattan, the City and State of New York, as one such office
or agency of the Company in accordance with Section 2.03.

Section 4.03    Reports.

        (a)     Whether or not required by the SEC's rules and regulations, so
long as any Notes are outstanding, the Company will furnish to the Holders of
Notes, within the time periods specified in the SEC's rules and regulations, (i)
all quarterly and annual reports that would be required to be filed with the SEC
on Forms 10-Q and 10-K if the Company were required to file such reports, and
(ii) all current reports that would be required to be filed with the SEC on Form
8-K if the Company were required to file such reports. All such reports shall be
prepared in all material respects in accordance with all of the SEC's rules and
regulations applicable to such reports. Each annual report on Form 10-K shall
include a report on the Company's consolidated financial statements by the
Company's certified independent accountants.

        In addition, the Company shall file a copy of each of the reports
referred to in clauses (i) and (ii) above with the SEC for public availability
within the time periods specified in the SEC's rules and regulations applicable
to such reports (unless the SEC will not accept such a filing) and shall make
such information available to securities analysts and prospective investors upon
request. The Company shall at all times comply with TIA Section 314(a).

        If, at any time, the Company is no longer subject to the periodic
reporting requirements of the Exchange Act for any reason, the Company shall
nevertheless continue filing the reports specified in the preceding paragraphs
on its website within the time periods that would apply if the Company were
required to file those reports with the SEC.

                                       40

<PAGE>

        (b)     In the case of any Notes that are originally issued as Transfer
Restricted Securities, the Company and the Guarantors shall furnish to the
holders of the Notes, prospective purchasers of the Notes and securities
analysts, upon their request, the information, if any, required to be delivered
pursuant to Rule 144A(d)(4) under the Securities Act.

Section 4.04    Compliance Certificate.

        (a)     The Company and each Guarantor (to the extent that such
Guarantor is so required under the TIA) shall deliver to the Trustee, within 90
days after the end of each fiscal year, an Officers' Certificate stating that a
review of the activities of the Company and its Restricted Subsidiaries during
the preceding fiscal year has been made under the supervision of the signing
Officers with a view to determining whether the Company has kept, observed,
performed and fulfilled its obligations under this Indenture, and further
stating, as to each such Officer signing such certificate, that to the best of
his or her knowledge the Company has kept, observed, performed and fulfilled
each and every covenant contained in this Indenture and is not in default in the
performance or observance of any of the terms, provisions and conditions of this
Indenture (or, if a Default or Event of Default shall have occurred, describing
all such Defaults or Events of Default of which he or she may have knowledge and
what action the Company is taking or proposes to take with respect thereto) and
that to the best of his or her knowledge no event has occurred and remains in
existence by reason of which payments on account of the principal of or
interest, if any, on the Notes is prohibited or if such event has occurred, a
description of the event and what action the Company is taking or proposes to
take with respect thereto.

        (b)     So long as not contrary to the then current recommendations of
the American Institute of Certified Public Accountants, the year-end financial
statements delivered pursuant to Section 4.03(a) above shall be accompanied by a
written statement of the Company's independent public accountants (who shall be
a firm of established national reputation) that in making the examination
necessary for certification of such financial statements, nothing has come to
their attention that would lead them to believe that the Company has violated
any provisions of Article 4 or Article 5 hereof or, if any such violation has
occurred, specifying the nature and period of existence thereof, it being
understood that such accountants shall not be liable directly or indirectly to
any Person for any failure to obtain knowledge of any such violation.

        (c)     The Company shall, so long as any of the Notes are outstanding,
deliver to the Trustee, forthwith upon any Officer becoming aware of any Default
or Event of Default, an Officers' Certificate specifying such Default or Event
of Default and what action the Company is taking or proposes to take with
respect thereto.

Section 4.05    Taxes.

        The Company shall pay, and shall cause each of its Subsidiaries to pay,
prior to delinquency, all material taxes, assessments, and governmental levies
except such as are contested in good faith and by appropriate proceedings or
where the failure to effect such payment is not adverse in any material respect
to the Holders of the Notes.

Section 4.06    Stay, Extension and Usury Laws.

        The Company and each of the Guarantors covenants (to the extent that it
may lawfully do so) that it shall not at any time insist upon, plead, or in any
manner whatsoever claim or take the benefit or advantage of, any stay, extension
or usury law wherever enacted, now or at any time hereafter in force, that may
affect the covenants or the performance of this Indenture; and the Company and
each of the Guarantors (to the extent that it may lawfully do so) hereby
expressly waives all benefit or advantage of

                                       41

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any such law, and covenants that it shall not, by resort to any such law,
hinder, delay or impede the execution of any power herein granted to the
Trustee, but shall suffer and permit the execution of every such power as though
no such law has been enacted.

Section 4.07    Restricted Payments.

        The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, directly or indirectly, (i) declare or pay any dividend or make
any other payment or distribution on account of the Company's or any of its
Restricted Subsidiaries' Equity Interests (including, without limitation, any
such payment in connection with any merger or consolidation involving the
Company) or to the direct or indirect holders of the Company's Equity Interests
in their capacity as such (other than dividends or distributions payable in
Equity Interests (other than Disqualified Stock) of the Company); (ii) purchase,
redeem or otherwise acquire or retire for value (including without limitation,
in connection with any merger or consolidation involving the Company) any Equity
Interests of the Company (other than any such Equity Interests owned by the
Company or any Restricted Subsidiary of the Company); (iii) make any payment on
or with respect to, or purchase, redeem, defease or otherwise acquire or retire
for value, any Indebtedness (other than intercompany Indebtedness between or
among the Company and its Restricted Subsidiaries) that is subordinated to the
Notes or the Subsidiary Guarantees, except a payment of interest or principal at
Stated Maturity (or within one year thereof); or (iv) make any Restricted
Investment (all such payments and other actions set forth in clauses (i) through
(iv) above being collectively referred to as "Restricted Payments"), unless, at
the time of and after giving effect to such Restricted Payment:

        (a)     no Default or Event of Default shall have occurred and be
continuing or would occur as a consequence thereof;

        (b)     the Company would, at the time of such Restricted Payment and
after giving pro forma effect thereto as if such Restricted Payment had been
made at the beginning of the applicable four-quarter period, have been permitted
to incur at least $1.00 of additional Indebtedness pursuant to the Consolidated
Interest Coverage Ratio test set forth in Section 4.09 hereof; and

        (c)     such Restricted Payment, together with the aggregate amount of
all other Restricted Payments made by the Company and its Restricted
Subsidiaries after the Issue Date (the amount expended for such purposes, if
other than cash, being the fair market value on the date of transfer or issue),
is less than the sum of the following amounts, without duplication: (A) 50% of
the Consolidated Net Income of the Company for the period (taken as one
accounting period) from January 1, 1998 to the end of the Company's most
recently ended fiscal quarter for which internal financial statements are
available at the time of such Restricted Payment (or, if such Consolidated Net
Income for such period is a deficit, less 100% of such deficit), plus (B) 100%
of the aggregate net cash proceeds and the fair market value of any non-cash
proceeds received by the Company from the issue or sale since November 12, 1999
of Equity Interests of the Company (other than Disqualified Stock and proceeds
received from the Issuance of Equity Interests in connection with the Merger) or
of Disqualified Stock or debt securities of the Company that have been converted
into such Equity Interests (other than any such Equity Interests, Disqualified
Stock or convertible debt securities sold to a Restricted Subsidiary of the
Company and other than Disqualified Stock or convertible debt securities that
have been converted into Disqualified Stock), plus (C) to the extent that any
Restricted Investment that was made after the Issue Date is or was sold for cash
or otherwise liquidated or repaid for cash, the cash return of capital with
respect to such Restricted Investment (less the cost of disposition, if any),
plus (D) in the event that any Unrestricted Subsidiary is redesignated as a
Restricted Subsidiary, the lesser of (1) an amount equal to the fair value of
the Company's Investments in such Restricted Subsidiary and (2) the amount of
Restricted Investments

                                       42

<PAGE>

previously made by the Company and its Restricted Subsidiaries in such
Unrestricted Subsidiary, plus (E) $10.0 million.

        So long as no Default shall have occurred and be continuing or would be
caused thereby, the foregoing provisions will not prohibit any of the following:
(a) the payment of any dividend within 60 days after the date of declaration
thereof, if at said date of declaration such payment would have complied with
the provisions of this Indenture; (b) the redemption, repurchase, retirement,
defeasance or other acquisition of any subordinated Indebtedness of the Company
or any Subsidiary Guarantor or Equity Interests of the Company in exchange for,
or out of the net cash proceeds of the substantially concurrent sale (other than
to a Subsidiary of the Company) of, other Equity Interests of the Company (other
than any Disqualified Stock), provided that the amount of any such net cash
proceeds that are utilized for any such redemption, repurchase, retirement,
defeasance or other acquisition shall be excluded from clause (iii)(B) of the
preceding paragraph; (c) the defeasance, redemption, repurchase, retirement or
other acquisition of subordinated Indebtedness of the Company or any Subsidiary
Guarantor with the net cash proceeds from an incurrence of, or in exchange for,
Permitted Refinancing Indebtedness; (d) the payment of any dividend or
distribution by a Restricted Subsidiary of the Company to the holders of its
common Equity Interests on a pro rata basis; (e) so long as no Default or Event
of Default shall have occurred and be continuing, the repurchase, redemption or
other acquisition or retirement for value of any Equity Interests of the Company
held by any employee of the Company or any of its Restricted Subsidiaries,
provided that the aggregate price paid for all such repurchased, redeemed,
acquired or retired Equity Interests shall not exceed $2.5 million in any
calendar year; (f) dividends to Parent to be used by Parent solely to pay its
fees required to maintain its corporate existence and to pay for general
corporate and overhead expenses incurred by Parent in the ordinary course of its
business; provided, however, that such dividends shall not exceed $500,000
million in any calendar year; provided further, however, that such dividends
shall be excluded in the calculation of the amount of Restricted Payments; (g)
dividends, distributions or advances to Parent to be used by Parent to pay
Federal, state and local taxes payable by Parent and directly attributable to
(or arising as a result of) the operations of the Company and the Restricted
Subsidiaries; provided, however, that (A) the amount of such dividends shall not
exceed the amount that the Company and its Restricted Subsidiaries would be
required to pay in respect of such Federal, state or local taxes were the
Company to pay such taxes as a stand-alone taxpayer and (B) such dividends
pursuant to this clause are used by Parent for such purposes within 10 days of
the receipt of such dividends; and (h) the acquisition of Equity Interests of
the Company in connection with the exercise of stock options or stock
appreciation rights by way of cashless exercise or in connection with the
satisfaction of withholding tax obligations. In determining the aggregate amount
of Restricted Payments made subsequent to the Issue Date in accordance with
clause (c) of the immediately preceding paragraph, amounts expended pursuant to
clauses (b), (c), (d), (f), (g) and (h) of this paragraph shall be excluded from
the calculation and amounts expended pursuant to clauses (a) and (e) of this
paragraph shall be included in the calculation.

        The Board of Directors may designate any Restricted Subsidiary to be an
Unrestricted Subsidiary if such designation would not cause a Default. For
purposes of making such determination, all outstanding Investments by the
Company and its Restricted Subsidiaries (except to the extent repaid in cash) in
the Subsidiary so designated shall be deemed to be Restricted Payments at the
time of such designation. All such outstanding Investments will be deemed to
constitute Investments in an amount equal to the greater of (a) the net book
value of such Investments at the time of such designation and (b) the fair
market value of such Investments at the time of such designation. Such
designation shall only be permitted if such Restricted Payment would be
permitted at such time and if such Restricted Subsidiary otherwise meets the
definition of an Unrestricted Subsidiary.

         The Board of Directors of the Company may at any time designate any
Unrestricted Subsidiary to be a Restricted Subsidiary, provided that such
designation shall be deemed to be an incurrence of

                                       43

<PAGE>

Indebtedness by a Restricted Subsidiary of the Company of any outstanding
Indebtedness of such Unrestricted Subsidiary and such designation shall only be
permitted if (a) such Indebtedness is permitted under Section 4.09 hereof,
calculated on a pro forma basis as if such designation had occurred at the
beginning of the four-quarter reference period, and (b) no Default or Event of
Default would be in existence following such designation.

        Any designation of a Subsidiary as an Unrestricted Subsidiary shall be
evidenced to the Trustee by filing with the Trustee a certified copy of a
resolution of the Board of Directors giving effect to such designation and an
Officers' Certificate certifying that such designation complied with the terms
of the definition of Unrestricted Subsidiary set forth in this Indenture and
with this Section 4.07.

        The amount of all Restricted Payments (other than cash) shall be the
fair market value on the date of the Restricted Payment of the asset(s) or
securities proposed to be transferred or issued by the Company or such
Restricted Subsidiary, as the case may be, pursuant to the Restricted Payment.

        The fair market value of any non-cash Restricted Payment shall be
determined in the manner contemplated by the definition of the term "fair market
value," and the results of such determination shall be evidenced by an Officers'
Certificate delivered to the Trustee. Not later than the date of making any
Restricted Payment, the Company shall deliver to the Trustee an Officers'
Certificate stating that such Restricted Payment is permitted and setting forth
the basis upon which the calculations required by this Section 4.07 were
computed; provided, however, with respect to any planned purchase or redemption
by the Company of its Equity Interests, the Company may, in advance of any such
purchase or redemption, deliver to the Trustee a single Officers' Certificate
that otherwise complies with requirements set forth above stating (i) the
maximum aggregate amount of Equity Interests to be purchased or redeemed and
(ii) the period over which such purchases or redemptions will occur.

Section 4.08    Dividend and Other Payment Restrictions Affecting Subsidiaries.

        The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, directly or indirectly, create or otherwise cause or suffer to
exist or become effective any encumbrance or restriction on the ability of any
Restricted Subsidiary to (a) pay dividends or make any other distributions to
the Company or any of its Restricted Subsidiaries on its Capital Stock or with
respect to any other interest or participation in, or measured by, its profits,
(b) pay any Indebtedness owed to the Company or any of its Restricted
Subsidiaries, (c) make loans or advances to the Company or any of its Restricted
Subsidiaries or (d) transfer any of its properties or assets to the Company or
any of its Restricted Subsidiaries, except for such encumbrances or restrictions
existing under or by reason of (1) Existing Indebtedness, as in effect on the
Issue Date, (2) this Indenture, the Notes and the Subsidiary Guarantees, (3)
applicable law, (4) any instrument governing Indebtedness or Capital Stock of a
Person acquired by the Company or any of its Restricted Subsidiaries as in
effect at the time of such acquisition (except to the extent such Indebtedness
was incurred in connection with or in contemplation of such acquisition), which
encumbrance or restriction is not applicable to any Person, or the properties or
assets of any Person, other than the Person, or the property or assets of the
Person, so acquired, provided that, in the case of Indebtedness, such
Indebtedness was permitted by the terms of this Indenture to be incurred, (5) by
reason of customary non-assignment provisions in leases entered into in the
ordinary course of business and consistent with past practices, (6) purchase
money obligations for property acquired in the ordinary course of business that
impose restrictions of the nature described in clause (c) above on the property
so acquired, (7) customary provisions in bona fide contracts for the sale of
property or assets (8) any agreement for the sale or other disposition of a
Subsidiary that restricts distributions by that Subsidiary pending its sale or
other disposition, (9) restrictions on cash or other deposits or net worth
imposed by customers under contracts entered into in the ordinary course of
business, (10) any encumbrance or restriction contained in the terms of any
Indebtedness, or any agreement pursuant to which such

                                       44

<PAGE>

Indebtedness was issued, if such encumbrance or restriction will not materially
affect the Company's ability to make principal or interest payments on the
Notes, as determined in good faith by the Company's Board of Directors, whose
determinations shall be conclusive, or (11) Permitted Refinancing Indebtedness
with respect to any Indebtedness referred to in clauses (1), (2) and (10) above,
provided that the restrictions contained in the agreements governing such
Permitted Refinancing Indebtedness are not materially more restrictive, taken as
a whole, than those contained in the agreements governing the Indebtedness being
refinanced.

Section 4.09    Incurrence of Indebtedness and Issuance of Disqualified Stock.

        The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, directly or indirectly, create, incur, issue, assume, guarantee
or otherwise become directly or indirectly liable, contingently or otherwise,
with respect to (collectively, "incur" or an "incurrence") any Indebtedness
other than Permitted Indebtedness and the Company will not issue any
Disqualified Stock and will not permit any of its Restricted Subsidiaries to
issue any shares of Disqualified Stock; provided, however, that the Company or
any Subsidiary Guarantor may incur Indebtedness, and the Company may issue
Disqualified Stock, if the Consolidated Interest Coverage Ratio for the
Company's most recently ended four full fiscal quarters for which internal
financial statements are available immediately preceding the date on which such
additional Indebtedness is incurred or such Disqualified Stock is issued would
have been at least 2.0 to 1.0, determined on a pro forma basis (including a pro
forma application of the net proceeds therefrom), as if the additional
Indebtedness or Disqualified Stock had been issued or incurred at the beginning
of such four-quarter period.

        The Company shall not incur any Indebtedness (including Permitted
Indebtedness) if that Indebtedness is contractually subordinated in right of
payment to any other Indebtedness of the Company, unless such Indebtedness is
also contractually subordinated in right of payment to the Notes on
substantially identical terms; provided, however, that no Indebtedness of the
Company will be deemed to be contractually subordinated in right of payment to
any other Indebtedness of the Company solely by virtue of being unsecured.

        For purposes of determining compliance with this Section 4.09, in the
event that an item of proposed Indebtedness meets the criteria of more than one
of the categories contained in clauses (a) through (m) of the definition of
"Permitted Indebtedness," or is entitled to be incurred pursuant to the first
paragraph of this Section 4.09, the Company shall be permitted to classify such
item of Indebtedness on the date of its incurrence, or later reclassify all or a
portion of such item of Indebtedness, in any manner that complies with this
Section 4.09.

Section 4.10    Asset Sales.

        The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, consummate an Asset Sale unless (a) the Company or such
Restricted Subsidiary, as the case may be, receives consideration at the time of
such Asset Sale at least equal to the fair market value (as determined in
accordance with the definition of such term, the results of which determination
shall be set forth in an Officers' Certificate delivered to the Trustee) of the
assets or Equity Interests issued or sold or otherwise disposed of and (b) at
least 75% of the consideration therefor received by the Company or such
Restricted Subsidiary, as the case may be, is in the form of cash or Cash
Equivalents; provided, however, that the amount of (i) any liabilities (as shown
on the Company's or such Restricted Subsidiary's most recent balance sheet) of
the Company or such Restricted Subsidiary (other than contingent liabilities and
liabilities that are by their terms subordinated to the Notes or any guarantee
thereof) that are assumed by the transferee of any such assets pursuant to a
customary novation agreement that releases the Company or such Restricted
Subsidiary from further liability and (ii) any securities, notes or other
obligations

                                       45

<PAGE>

received by the Company or such Restricted Subsidiary from such transferee that
are converted by the Company or such Restricted Subsidiary into cash within 90
days of the receipt thereof (to the extent of the cash received) shall be deemed
to be cash for purposes of this Section 4.10.

        Within 365 days after the receipt of any Net Proceeds from an Asset
Sale, the Company or any such Restricted Subsidiary may apply such Net Proceeds
to (a) permanently repay the principal of any secured Indebtedness (to the
extent of the fair value of the assets securing such Indebtedness, as determined
by the Board of Directors), (b) make a capital expenditure, or (c) acquire
(including by way of a purchase of assets or stock, merger, consolidation or
otherwise) assets used in the Principal Business. (Any such Net Proceeds that
are applied to the acquisition of assets used in the Principal Business pursuant
to any binding agreement shall be deemed to have been applied for such purpose
within such 365-day period so long as they are so applied within two years after
the date of receipt of such Net Proceeds.) Pending the final application of any
such Net Proceeds, the Company or any such Restricted Subsidiary may temporarily
reduce outstanding revolving credit borrowings, or otherwise invest such Net
Proceeds in any manner that is not prohibited by this Indenture. Any Net
Proceeds from Asset Sales that are not applied or invested as provided in the
first sentence of this paragraph shall be deemed to constitute "Excess
Proceeds." Within 30 days of each date on which the aggregate amount of Excess
Proceeds exceeds $20.0 million, the Company shall commence an Asset Sale Offer
pursuant to Section 3.09 hereof to purchase the maximum principal amount of
Notes that may be purchased out of Excess Proceeds. The offer price in any Asset
Sale Offer will be equal to 100% of the principal amount thereof, plus accrued
and unpaid interest and Liquidated Damages, if any, thereon, to the date of
purchase and payable in cash, in accordance with the procedures set forth in
Section 3.09 hereof; provided, however, that, if the Company is required to
apply such Excess Proceeds to repurchase, or to offer to repurchase, any Pari
Passu Indebtedness, the Company shall only be required to offer to repurchase
the maximum principal amount of Notes that may be purchased out of the amount of
such Excess Proceeds multiplied by a fraction, the numerator of which is the
aggregate principal amount of Notes outstanding and the denominator of which is
the aggregate principal amount of Notes outstanding plus the aggregate principal
amount of Pari Passu Indebtedness outstanding. To the extent that the aggregate
principal amount of Notes tendered pursuant to an Asset Sale Offer is less than
the amount that the Company is required to repurchase, the Company may use any
remaining Excess Proceeds for purposes not otherwise prohibited by this
Indenture. If the aggregate principal amount of Notes surrendered by holders
thereof exceeds the amount that the Company is required to repurchase, the
Trustee shall select the Notes to be purchased on a pro rata basis (with such
adjustments as may be deemed appropriate by the Trustee so that only Notes in
denominations of $1,000, or integral multiples thereof, shall be purchased).
Upon completion of such offer to purchase, the amount of Excess Proceeds shall
be reset at zero.

Section 4.11    Transactions with Affiliates.

        The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, make any payment to, or sell, lease, transfer or otherwise
dispose of any of its properties or assets to, or purchase any property or
assets from, or enter into or make or amend any transaction, contract,
agreement, understanding, loan, advance or guarantee with, or for the benefit
of, any Affiliate (each of the foregoing, an "Affiliate Transaction"), unless
(a) such Affiliate Transaction is on terms that are no less favorable to the
Company or the relevant Restricted Subsidiary than those that would have been
obtained in a comparable transaction by the Company or such Restricted
Subsidiary with an unrelated Person or, if there is no such comparable
transaction, on terms that are fair and reasonable to the Company or such
Restricted Subsidiary, and (b) the Company delivers to the Trustee (i) with
respect to any Affiliate Transaction or series of related Affiliate Transactions
involving aggregate consideration in excess of $10.0 million, a resolution of
the Board of Directors set forth in an Officers' Certificate certifying that
such Affiliate Transaction complies with clause (a) above and that such
Affiliate Transaction has been approved by a majority of the disinterested
members of the Board of Directors and (ii) with respect to any

                                       46

<PAGE>

Affiliate Transaction or series of related Affiliate Transactions involving
aggregate consideration in excess of $25.0 million, an opinion as to the
fairness to the Company or the relevant Subsidiary of such Affiliate Transaction
from a financial point of view issued by an accounting, appraisal or investment
banking firm that is, in the judgment of the Board of Directors, qualified to
render such opinion and is independent with respect to the Company; provided,
however, that the following shall be deemed not to be Affiliate Transactions:
(A) any employment agreement or other employee compensation plan or arrangement
entered into by the Company or any of its Restricted Subsidiaries in the
ordinary course of business of the Company or such Restricted Subsidiary; (B)
transactions between or among the Company and its Restricted Subsidiaries; (C)
Permitted Investments and Restricted Payments that are permitted by the
provisions of this Indenture; (D) advances to officers, directors and employees
of the Company or any Restricted Subsidiary made in the ordinary course of
business in an aggregate amount not to exceed $1.0 million outstanding at any
one time; (E) indemnities of officers, directors and employees of the Company or
any Restricted Subsidiary permitted by by-law or statutory provisions; (F) the
consummation of the Escrow Corp. Merger, the Merger and related transactions;
and (G) the payment of reasonable and customary regular fees to directors of the
Company or any of its Restricted Subsidiaries.

Section 4.12    Liens.

        The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, directly or indirectly, create, incur, assume or suffer to
exist any Lien on any asset owned on the Issue Date or acquired after the Issue
Date, or any income or profits therefrom, or assign or convey any right to
receive income therefrom, except Permitted Liens, to secure (a) any Indebtedness
of the Company or such Restricted Subsidiary (if it is not also a Subsidiary
Guarantor), unless prior to, or contemporaneously therewith, the Notes are
equally and ratably secured, or (b) any Indebtedness of any Guarantor, unless
prior to, or contemporaneously therewith, the Subsidiary Guarantees are equally
and ratably secured; provided, however, that if such Indebtedness is expressly
subordinated to the Notes or the Subsidiary Guarantees, the Lien securing such
Indebtedness will be subordinated and junior to the Lien securing the Notes or
the Subsidiary Guarantees, as the case may be, with the same relative priority
as such Indebtedness has with respect to the Notes or the Subsidiary Guarantees.

Section 4.13    Guarantees.

        Upon consummation of the Mergers, the Company shall cause each of its
Domestic Subsidiaries (including after giving effect to the Mergers) to become a
Guarantor and execute a supplemental indenture and a Subsidiary Guarantee and an
Opinion of Counsel and an Officers' Certificate in accordance with the terms of
Section 12.04 of this Indenture satisfactory to the Trustee. Thereafter, if the
Company or any of its Restricted Subsidiaries acquires or creates another
Domestic Subsidiary, then that newly-acquired or created Domestic Subsidiary
shall become a Guarantor and execute a supplemental indenture and a Subsidiary
Guarantee and an Opinion of Counsel and an Officers' Certificate in accordance
with the terms of Section 12.04 of this Indenture satisfactory to the Trustee
within ten Business Days of the date on which it was acquired or created.

Section 4.14    Corporate Existence.

        Subject to Article 5 hereof, the Company shall do or cause to be done
all things necessary to preserve and keep in full force and effect (i) its
corporate existence, and, subject to Article 10 hereof, the corporate,
partnership or other existence of each of its Restricted Subsidiaries, in
accordance with the respective organizational documents (as the same may be
amended from time to time) of the Company or any such Restricted Subsidiary and
(ii) the rights (charter and statutory), licenses and franchises of the Company
and its Restricted Subsidiaries; provided, however, that the Company shall not
be required to preserve any such right, license or franchise, or the corporate,
partnership or other existence of any of its

                                       47

<PAGE>

Restricted Subsidiaries, if the Board of Directors shall determine that the
preservation thereof is no longer desirable in the conduct of the business of
the Company and its Restricted Subsidiaries, taken as a whole, and that the loss
thereof is not adverse in any material respect to the Holders of the Notes.

Section 4.15    Offer to Repurchase Upon Change of Control.

        (a)     Upon the occurrence of a Change of Control, the Company shall
make an offer (a "Change of Control Offer") to repurchase all or any part (equal
to $1,000 or an integral multiple thereof) of each Holder's Notes at an offer
price in cash equal to 101% of the aggregate principal amount thereof, plus
accrued and unpaid interest and Liquidated Damages, if any, thereon to the date
of repurchase (the "Change of Control Payment"). Within 30 days following a
Change of Control, the Company shall mail a notice to each Holder with a copy to
the Trustee stating: (1) that the Change of Control Offer is being made pursuant
to this Section 4.15 and that all Notes validly tendered and not withdrawn will
be accepted for payment; (2) the purchase price and the purchase date, which
shall be no earlier than 30 days but no later than 60 days from the date such
notice is mailed (the "Change of Control Payment Date"); (3) that any Note not
tendered will continue to accrue interest and Liquidated Damages, if any; (4)
that, unless the Company defaults in the payment of the Change of Control
Payment, all Notes accepted for payment pursuant to the Change of Control Offer
shall cease to accrue interest and Liquidated Damages, if any, after the Change
of Control Payment Date; (5) that Holders electing to have any Notes purchased
pursuant to a Change of Control Offer will be required to surrender the Notes,
properly endorsed for transfer, together with the form entitled "Option of
Holder to Elect Purchase" on the reverse of the Notes completed and such
customary documents as the Company may reasonably request, to the Paying Agent
at the address specified in the notice prior to the close of business on the
third Business Day preceding the Change of Control Payment Date; (6) that
Holders will be entitled to withdraw their election if the Paying Agent
receives, not later than the close of business on the second Business Day
preceding the Change of Control Payment Date, a telegram, telex, facsimile
transmission or letter setting forth the name of the Holder, the principal
amount of Notes delivered for purchase, and a statement that such Holder is
withdrawing his election to have the Notes purchased; and (7) that Holders whose
Notes are being purchased only in part will be issued new Notes equal in
principal amount to the unpurchased portion of the Notes surrendered, which
unpurchased portion must be equal to $1,000 in principal amount or an integral
multiple thereof. If any of the Notes subject to a Change of Control Offer is in
the form of a Global Note, then the Company shall modify such notice to the
extent necessary to accord with the procedures of the Depository applicable to
repurchases. Further, the Company shall comply with the requirements of Rule
14e-1 under the Exchange Act and any other securities laws and regulations
thereunder to the extent such laws and regulations are applicable in connection
with the repurchase of Notes as a result of a Change of Control. To the extent
that the provision of any securities laws or regulations conflict with this
Section 4.15, the Company shall comply with the applicable securities laws and
regulations and shall not be deemed to have breached its obligations under this
Section 4.15 by virtue of such conflict.

        (b)     On or before 10:00 a.m. New York time on the Change of Control
Payment Date, the Company shall, to the extent lawful, (a) accept for payment
all Notes or portions thereof properly tendered pursuant to the Change of
Control Offer, (b) deposit with the Paying Agent an amount equal to the Change
of Control Payment in respect of all Notes or portions of Notes properly
tendered and (c) deliver or cause to be delivered to the Trustee the Notes so
accepted together with an Officers' Certificate stating the aggregate principal
amount of Notes or portions thereof being purchased by the Company. The Paying
Agent shall promptly mail to each holder of Notes properly tendered the Change
of Control Payment for such Notes, and the Trustee shall promptly authenticate
and mail (or cause to be transferred by book entry) to each Holder a new Note
equal in principal amount to any unpurchased portion of the Notes surrendered,
if any; provided, however, that each such new Note will be in a principal amount
of

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<PAGE>

$1,000 or an integral multiple thereof. The Company shall publicly announce the
results of the Change of Control Offer on or as soon as practicable after the
Change of Control Payment Date.

        (c)     The Change of Control provisions described above shall be
applicable whether or nor any other provisions of this Indenture are applicable.

        (d)     The Company shall not be required to make a Change of Control
Offer following a Change of Control if a third party makes the Change of Control
Offer in the manner, at the time and otherwise in compliance with the
requirements set forth in this Section 4.15 and Section 3.09 hereof and
purchases all Notes validly tendered and not withdrawn under such Change of
Control Offer.

Section 4.16    Sale-and-Leaseback Transactions.

        The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, enter into any sale-and-leaseback transaction; provided,
however, that the Company or any Restricted Subsidiary, as applicable, may enter
into a sale-and-leaseback transaction if (i) the Company or such Restricted
Subsidiary could have (a) incurred Indebtedness in an amount equal to the
Attributable Indebtedness relating to such sale-and-leaseback transaction
pursuant to the Consolidated Interest Coverage Ratio test set forth in Section
4.09 hereof and (b) incurred a Lien to secure such Indebtedness pursuant to
Section 4.12 hereof, (ii) the gross cash proceeds of such sale-and-leaseback
transaction are at least equal to the fair market value (as determined in
accordance with the definition of such term, the results of which determination
shall be set forth in an Officers' Certificate delivered to the Trustee) of the
property that is the subject of such sale-and-leaseback transaction and (iii)
the transfer of assets in such sale-and-leaseback transaction is permitted by,
and the Company applies the proceeds of such transaction in compliance with,
Section 4.10 hereof.

Section 4.17    No Inducements.

        Each of the Company and Parent shall not, and the Company shall not
permit any of its Subsidiaries, either directly or indirectly, to pay (or cause
to be paid) any consideration, whether by way of interest, fee or otherwise, to
any Holder for or as an inducement to any consent, waiver, amendment or
supplement of any terms or provisions of this Indenture, the Notes or the
Guarantees, unless such consideration is offered to be paid (or agreed to be
paid) to all Holders which so consent, waive or agree to amend or supplement in
the time frame set forth on solicitation documents relating to such consent,
waiver or agreement.

Section 4.18    Line of Business.

        The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, engage in any business or activity other than the Principal
Business.

Section 4.19    Limitations on Frontier Escrow Corporation.

        From the date of this Indenture until the consummation of the Escrow
Corp. Merger, Frontier Escrow Corporation shall take no actions other than those
specifically permitted pursuant to the terms of the Escrow Agreement related to
making the Deposit into the Escrow Account (as defined in the Escrow Agreement)
and the release of the funds in connection with to the consummation of the
Escrow Corp. Merger. Frontier Escrow Corporation shall not hold any assets other
than the Escrow Account and the proceeds thereof and shall not become liable for
any obligations other than the Notes and this Indenture and those incidental to
its organization and pursuant to the Escrow Agreement. In connection with the
Escrow Corp. Merger, Frontier Escrow Corporation shall cause the entity known,
on the date of this

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Indenture, as Frontier Oil Corporation to execute an Assumption Agreement
substantially in the form attached as Exhibit G hereto.

Section 4.20    Changes in Covenants when Notes Rated Investment Grade.

        If on any date following the date of this Indenture (i) the Notes are
rated Baa3 or better by Moody's and BBB- or better by S&P (or, if either such
entity ceases to rate the Notes for reasons outside of the control of the
Company, the equivalent investment grade credit rating from any other
"nationally recognized statistical rating organization" within the meaning of
Rule 15c3-1(c)(2)(vi)(F) under the Exchange Act selected by the Company as a
replacement agency), and (ii) no Default or Event of Default shall have occurred
and be continuing, then, beginning on that day and continuing at all times
thereafter regardless of any subsequent changes in the rating of the Notes, the
covenants contained in Sections 3.09, 4.07, 4.08, 4.09, 4.10, 4.11, 4.16 and
clause (d) of Section 5.01 shall no longer be applicable to the Notes, such that
the Company may omit to comply with and shall have no liability in respect of
any term, condition or limitation set forth in any such covenant, whether
directly or indirectly, by reason of any reference elsewhere herein to any such
covenant or by reason of any reference in any such covenant to any other
provision herein or in any other document and such omission to comply shall not
constitute a Default or an Event of Default under Section 6.01 hereof.

                                   ARTICLE 5.
                                   SUCCESSORS

Section 5.01    Merger, Consolidation, or Sale of Assets.

        The Company shall not consolidate or merge with or into (whether or not
the Company is the surviving corporation), or sell, assign, transfer, convey or
otherwise dispose of all or substantially all of its properties or assets in one
or more related transactions, to another Person unless (a) either: (i) the
Company is the surviving corporation or (ii) the Person formed by or surviving
any such consolidation or merger (if other than the Company) or to which such
sale, assignment, transfer, conveyance or other disposition shall have been made
is a corporation organized or existing under the laws of the United States, any
state thereof or the District of Columbia, (b) the Person formed by or surviving
any such consolidation or merger (if other than the Company) or the Person to
which such sale, assignment, transfer, conveyance or other disposition shall
have been made assumes all of the obligations of the Company under the Notes,
this Indenture and the Registration Rights Agreement pursuant to agreements
reasonably satisfactory to the Trustee, (c) immediately after such transaction
no Default or Event of Default exists and (d) except in the case of a merger of
the Company with or into a Restricted Subsidiary of the Company, the Company or
the Person formed by or surviving any such consolidation or merger (if other
than the Company), or the Person to which such sale, assignment, transfer,
conveyance or other disposition shall have been made will, at the time of such
transaction and after giving pro forma effect thereto as if such transaction had
occurred at the beginning of the applicable four-quarter period, be permitted to
incur at least $1.00 of additional Indebtedness pursuant to the Consolidated
Interest Coverage Ratio test set forth in Section 4.09 hereof.

        In addition, the Company may not, directly or indirectly, lease all or
substantially all of its properties or assets, in one or more related
transactions, to any other Person.

        In connection with any consolidation, merger or disposition contemplated
by this provision, the Company shall deliver, or cause to be delivered, to the
Trustee, in form and substance reasonably satisfactory to the Trustee, (i) an
Officers' Certificate stating that such consolidation, merger or disposition and
agreements in respect thereto comply with this provision and that all conditions
precedent

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<PAGE>

in this Indenture provided for relating to such transaction or transactions have
been complied with and (ii) an Opinion of Counsel stating that the requirements
of Section 5.01(a) and (b) have been satisfied.

        Notwithstanding the foregoing, each of Frontier Oil Corporation and
Frontier Escrow Corporation may consummate the Escrow Corp. Merger, the Merger
and related transactions without compliance with this Article 5.

Section 5.02    Successor Corporation Substituted.

        Upon any consolidation or merger, or any sale, assignment, transfer,
conveyance or other disposition of all or substantially all of the properties or
assets of the Company in a transaction that is subject to, and that complies
with the provisions of, Section 5.01 hereof, the successor corporation formed by
such consolidation or into or with which the Company is merged or to which such
sale, assignment, transfer, conveyance or other disposition is made shall
succeed to, and be substituted for (so that from and after the date of such
consolidation, merger, sale, assignment, transfer, conveyance or other
disposition, the provisions of this Indenture referring to the "Company" shall
refer instead to the successor corporation and not to the Company), and may
exercise every right and power of the Company under this Indenture with the same
effect as if such successor Person had been named as the Company herein;
provided, however, that the predecessor Company shall not be relieved from its
obligations under this Indenture or the Notes except in the case of a sale of
all or the Company's assets in a transaction that is subject to, and that
complies with the provisions of, Section 5.01 hereof.

                                   ARTICLE 6.
                              DEFAULTS AND REMEDIES

Section 6.01    Events of Default.

        An "Event of Default" occurs if:

        (a)     the Company defaults in the payment when due of interest on, or
Liquidated Damages, if any, with respect to, the Notes, and such default
continues for a period of 30 days;

        (b)     the Company defaults in the payment when due of principal of or
premium, if any, on the Notes;

        (c)     the Company or any of its Subsidiaries or Parent fails to comply
with any of the provisions of Section 4.15 or 5.01 hereof; (d) Frontier Escrow
Corporation fails to comply with the provisions of Section 4.19 hereof;

        (e)     the Company or any of its Subsidiaries fails to observe or
perform any other covenant or other agreement in this Indenture, the Notes or
the Escrow Agreement for 60 days after notice of such failure to the Company by
the Trustee or the Holders of at least 25% in principal amount of the Notes then
outstanding, voting as a single class;

        (f)     a default occurs under any mortgage, indenture or instrument
under which there may be issued or by which there may be secured or evidenced
any Indebtedness for money borrowed by the Company or any of its Restricted
Subsidiaries or Parent (or the payment of which is guaranteed by the Company or
any of its Restricted Subsidiaries or Parent), whether such Indebtedness or
guarantee now exists, or is created after the Issue Date, which default (i) is
caused by a failure to pay principal of or premium or interest on such
Indebtedness prior to the expiration of any grace period provided in such

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Indebtedness (a "Payment Default") or (ii) results in the acceleration of such
Indebtedness prior to its express maturity and, in each case, the principal
amount of any such Indebtedness, together with the principal amount of any other
such Indebtedness under which there has been a Payment Default or the maturity
of which has been so accelerated, aggregates $10.0 million or more; and
provided, further, that if such default is cured or waived or any such
acceleration rescinded, or such Indebtedness is repaid, within a period of ten
days from the continuation of such default beyond the applicable grace period or
the occurrence of such acceleration, as the case may be, an Event of Default and
any consequential acceleration of the Notes shall be automatically rescinded, so
long as such rescission does not conflict with any judgment or decree;

        (g)     a final judgment or final judgments for the payment of money are
entered by a court or courts of competent jurisdiction against the Company or
any of its Restricted Subsidiaries or Parent and such judgment or judgments are
not paid or discharged for a period (during which execution shall not be
effectively stayed) of 60 days, provided that the aggregate of all such
undischarged judgments exceeds $10.0 million (net of applicable insurance
coverage which is acknowledged in writing by the insurer);

        (h)     the failure of Parent to execute a supplemental indenture and a
Guarantee upon consummation of the Mergers;

        (i)     the failure of any Guarantor to perform any covenant set forth
in its Guarantee or the repudiation by any Guarantor of its obligations under
its Guarantee or the unenforceability of any Guarantee against a Guarantor for
any reason;

        (j)     the failure of the Escrow Agreement, at any time, to be in full
force and effect (unless the Deposit is released by the Escrow Agent in
accordance with the terms of the Escrow Agreement) or any contest by the Company
or any of its Subsidiaries of the validity or enforceability of the Escrow
Agreement;

        (k)     the Company, Parent, any Restricted Subsidiary that is also a
Significant Subsidiary or any group of Subsidiaries that, taken as a whole,
would constitute a Significant Subsidiary, pursuant to or within the meaning of
Bankruptcy Law:

                (i)     commences a voluntary case,

                (ii)    consents to the entry of an order for relief against it
        in an involuntary case,

                (iii)   consents to the appointment of a Custodian of it or for
        all or substantially all of its property,

                (iv)    makes a general assignment for the benefit of its
        creditors, or

                (v)     generally is not paying its debts as they become due; or

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

                (i)     is for relief against the Company, Parent, any
        Restricted Subsidiary that is also a Significant Subsidiary or any group
        of Subsidiaries that, taken as a whole, would constitute a Significant
        Subsidiary in an involuntary case,

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<PAGE>

                (ii)    appoints a Custodian of the Company, Parent, any
        Restricted Subsidiary that is also a Significant Subsidiary or any group
        of Subsidiaries that, taken as a whole, would constitute a Significant
        Subsidiary for all or substantially all of the property of the Company,
        Parent, any Restricted Subsidiary that is also a Significant Subsidiary
        or any group of Subsidiaries that, taken as a whole, would constitute a
        Significant Subsidiary, or

                (iii)   orders the liquidation of the Company, Parent, any
        Restricted Subsidiary that is also a Significant Subsidiary or any group
        of Subsidiaries that, taken as a whole, would constitute a Significant
        Subsidiary, and the order or decree remains unstayed and in effect for
        60 consecutive days.

Section 6.02    Acceleration.

        If any Event of Default occurs and is continuing, the Trustee or the
Holders of at least 25% in principal amount of the then outstanding Notes may
declare all of the Notes to be due and payable immediately. Upon any such
declaration, the Notes shall become due and payable immediately. Notwithstanding
the foregoing, if an Event of Default specified in clause (k) or (l) of Section
6.01 hereof occurs with respect to the Company, Parent, any Restricted
Subsidiary that is also a Significant Subsidiary or any group of Subsidiaries
that, taken as a whole, would constitute a Significant Subsidiary, all
outstanding Notes shall be due and payable immediately without further action or
notice. The Holders of a majority in aggregate principal amount of the then
outstanding Notes by written notice to the Trustee may on behalf of all of the
Holders rescind an acceleration and its consequences if the rescission would not
conflict with any judgment or decree and if all existing Events of Default
(except nonpayment of principal, interest, premium or Liquidated Damages, if
any, that have become due solely because of the acceleration) have been cured or
waived.

        If an Event of Default occurs by reason of any willful action (or
inaction) taken (or not taken) by or on behalf of the Company with the intention
of avoiding payment of the premium that the Company would have had to pay if the
Company then had elected to redeem the Notes pursuant to Section 3.07 hereof,
then, upon acceleration of the Notes, an equivalent premium shall also become
and be immediately due and payable, to the extent permitted by law, anything in
this Indenture or in the Notes to the contrary notwithstanding.

        If an Event of Default occurs prior to April 15, 2008, by reason of any
willful action (or inaction) taken (or not taken) by or on behalf of the Company
with the intention of avoiding the prohibition on redemption of the Notes prior
to such date, then, upon acceleration of the Notes, an additional premium shall
also become and be immediately due and payable in an amount, for each of the
years beginning on April 15 of the years set forth below, as set forth below
(expressed as percentages of the principal amount of the Notes on the date of
payment that would otherwise be due but for the provisions of this sentence):

                   YEAR                      PERCENTAGE
                   ----                      ----------
                   2003                        8.000%
                   2004                        7.200%
                   2005                        6.400%
                   2006                        5.600%
                   2007                        4.800%

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Section 6.03    Other Remedies.

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

        The Trustee may maintain a proceeding even if it does not possess any of
the Notes or does not produce any of them in the proceeding. A delay or omission
by the Trustee or any Holder of a Note in exercising any right or remedy
accruing upon an Event of Default shall not impair the right or remedy or
constitute a waiver of or acquiescence in the Event of Default. All remedies are
cumulative to the extent permitted by law.

Section 6.04    Waiver of Past Defaults.

        Holders of not less than a majority in aggregate principal amount of the
then outstanding Notes by notice to the Trustee may on behalf of the Holders of
all of the Notes waive any existing Default or Event of Default and its
consequences hereunder, except a continuing Default or Event of Default in the
payment of the principal of or premium, interest or Liquidated Damages, if any,
on the Notes (including in connection with an offer to purchase); provided,
however, that the Holders of a majority in aggregate principal amount of the
then outstanding Notes may rescind an acceleration and its consequences,
including any related payment default that resulted from such acceleration. Upon
any such waiver, such Default shall cease to exist, and any Event of Default
arising therefrom shall be deemed to have been cured for every purpose of this
Indenture; but no such waiver shall extend to any subsequent or other Default or
impair any right consequent thereon.

Section 6.05    Control by Majority.

        Holders of a majority in principal amount of the then outstanding Notes
may direct the time, method and place of conducting any proceeding for
exercising any remedy available to the Trustee or exercising any trust or power
conferred on it. However, the Trustee may refuse to follow any direction that
conflicts with law or this Indenture or that the Trustee determines may be
unduly prejudicial to the rights of other Holders of Notes or that may involve
the Trustee in personal liability.

Section 6.06    Limitation on Suits.

        A Holder of a Note may pursue a remedy with respect to this Indenture or
the Notes only if:

        (a)     the Holder of a Note gives to the Trustee written notice of a
continuing Event of Default;

        (b)     the Holders of at least 25% in principal amount of the then
outstanding Notes make a written request to the Trustee to pursue the remedy;

        (c)     such Holder of a Note or Holders of Notes offer and, if
requested, provide to the Trustee indemnity satisfactory to the Trustee against
any loss, liability or expense;

        (d)     the Trustee does not comply with the request within 60 days
after receipt of the request and the offer and, if requested, the provision of
indemnity; and

        (e)     during such 60-day period the Holders of a majority in principal
amount of the then outstanding Notes do not give the Trustee a direction
inconsistent with the request.

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<PAGE>

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

Section 6.07    Rights of Holders of Notes to Receive Payment.

        Notwithstanding any other provision of this Indenture, the right of any
Holder of a Note to receive payment of principal of and premium, interest and
Liquidated Damages, if any, on the Note, on or after the respective due dates
expressed in the Note (including in connection with an offer to purchase), or to
bring suit for the enforcement of any such payment on or after such respective
dates, shall not be impaired or affected without the consent of such Holder.

Section 6.08    Collection Suit by Trustee.

        If an Event of Default specified in Section 6.01(a) or (b) occurs and is
continuing, the Trustee is authorized to recover judgment in its own name and as
trustee of an express trust against the Company for the whole amount of
principal of, premium, interest and Liquidated Damages, if any, remaining unpaid
on the Notes and interest on overdue principal and, to the extent lawful,
interest and Liquidated Damages, if any, and such further amount as shall be
sufficient to cover the costs and expenses of collection, including the
reasonable compensation, expenses, disbursements and advances of the Trustee,
its agents and counsel.

Section 6.09    Trustee May File Proofs of Claim.

        The Trustee is authorized 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 (including any claim for the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel) and the
Holders of the Notes allowed in any judicial proceedings relative to the Company
(or any other obligor upon the Notes), its creditors or its property and shall
be entitled and empowered to collect, receive and distribute any money or other
property payable or deliverable on any such claims and any custodian in any such
judicial proceeding is hereby authorized by each Holder 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 to
it for the reasonable compensation, expenses, disbursements and advances of the
Trustee, its agents and counsel, and any other amounts due the Trustee under
Section 7.07 hereof. To the extent that the payment of any such compensation,
expenses, disbursements and advances of the Trustee, its agents and counsel, and
any other amounts due the Trustee under Section 7.07 hereof out of the estate in
any such proceeding, 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, money, securities and other properties that the Holders may be
entitled to receive in such proceeding whether in liquidation or under any plan
of reorganization or arrangement or otherwise. Nothing herein contained shall be
deemed to authorize the Trustee to authorize or consent to or accept or adopt on
behalf of any Holder any plan of reorganization, arrangement, adjustment or
composition affecting the Notes or the rights of any Holder, or to authorize the
Trustee to vote in respect of the claim of any Holder in any such proceeding.

Section 6.10    Priorities.

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

                First: to the Trustee, its agents and attorneys for amounts due
        under Section 7.07 hereof, including payment of all compensation,
        expense and liabilities incurred, and all advances made, by the Trustee
        and the Trustee's costs and expenses of collection;

                                       55

<PAGE>

                Second: to Holders of Notes for amounts due and unpaid on the
        Notes for principal, premium, interest and Liquidated Damages, if any,
        ratably, without preference or priority of any kind, according to the
        amounts due and payable on the Notes for principal, premium, interest
        and Liquidated Damages, if any, respectively; and

                Third: to the Company or to such party as a court of competent
        jurisdiction shall direct.

        The Trustee may fix a record date and payment date for any payment to
Holders of Notes pursuant to this Section 6.10.

Section 6.11    Undertaking for Costs.

        In any suit for the enforcement of any right or remedy under this
Indenture or in any suit against the Trustee for any action taken or omitted by
it as a Trustee, a court in its discretion may require the filing by any party
litigant in the suit of an undertaking to pay the costs of the suit, and the
court in its discretion may assess reasonable costs, including reasonable
attorneys' fees, against any party litigant in the suit, having due regard to
the merits and good faith of the claims or defenses made by the party litigant.
This Section does not apply to a suit by the Trustee, a suit by a Holder of a
Note pursuant to Section 6.07 hereof, or a suit by Holders of more than 10% in
principal amount of the then outstanding Notes.

                                   ARTICLE 7.
                                     TRUSTEE

Section 7.01    Duties of Trustee.

        (a)     If an Event of Default has occurred and is continuing, the
Trustee shall exercise such of the rights and powers vested in it by this
Indenture, and use the same degree of care and skill in its exercise, as a
prudent person would exercise or use under the circumstances in the conduct of
such person's own affairs.

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

                (i)     the duties of the Trustee shall be determined solely by
        the express provisions of this Indenture and the Trustee need perform
        only those duties that are specifically set forth in this Indenture and
        no others, and no implied covenants or obligations shall be read into
        this Indenture against the Trustee; and

                (ii)    in the absence of bad faith on its part, the Trustee may
        conclusively rely, as to the truth of the statements and the correctness
        of the opinions expressed therein, upon certificates or opinions
        furnished to the Trustee and conforming to the requirements of this
        Indenture. However, the Trustee shall examine the certificates and
        opinions to determine whether or not they conform to the requirements of
        this Indenture.

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

                (i)     this paragraph does not limit the effect of paragraph
        (b) of this Section 7.01;

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<PAGE>

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

                (iii)   the Trustee shall not be liable with respect to any
        action it takes or omits to take in good faith in accordance with a
        direction received by it pursuant to Section 6.05 hereof.

        (d)     Whether or not therein expressly so provided, every provision of
this Indenture, the Notes and the Guarantees that in any way relates to the
Trustee is subject to paragraphs (a), (b) and (c) of this Section 7.01.

        (e)     No provision of this Indenture shall require the Trustee to
expend or risk its own funds or incur any liability. The Trustee shall be under
no obligation to exercise any of its rights and powers under this Indenture at
the request of any Holders, unless such Holder shall have offered to the Trustee
security and indemnity satisfactory to it against any loss, liability or
expense.

        (f)     The Trustee shall not be liable for interest on any money
received by it except as the Trustee may agree in writing with the Company.
Money held in trust by the Trustee need not be segregated from other funds
except to the extent required by law.

Section 7.02    Rights of Trustee.

        (a)     The Trustee may conclusively rely upon any document believed by
it to be genuine and to have been signed or presented by the proper Person. The
Trustee need not investigate any fact or matter stated in the document.

        (b)     Before the Trustee acts or refrains from acting, it may require
an Officers' Certificate or an Opinion of Counsel or both. The Trustee shall not
be liable for any action it takes or omits to take in good faith in reliance on
such Officers' Certificate or Opinion of Counsel. The Trustee may consult with
counsel and the written advice of such counsel or any Opinion of Counsel shall
be full and complete authorization and protection from liability in respect of
any action taken, suffered or omitted by it hereunder in good faith and in
reliance thereon.

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

        (d)     The Trustee shall not be liable for any action it takes or omits
to take in good faith that it believes to be authorized or within the rights or
powers conferred upon it by this Indenture.

        (e)     Unless otherwise specifically provided in this Indenture, any
demand, request, direction or notice from the Company shall be sufficient if
signed by an Officer of the Company.

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

        (g)     The Trustee shall have no duty to inquire as to the performance
of the Company's covenants in Article 4 hereof. In addition, the Trustee shall
not be deemed to have knowledge of any Default or Event of Default except: (1)
any Event of Default occurring pursuant to Section 6.01(a) or

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<PAGE>

6.01(b) hereof; or (2) any Default or Event of Default of which is Responsible
Officer shall have received written notification or obtained actual knowledge.

Section 7.03    Individual Rights of Trustee.

        The Trustee in its individual or any other capacity may become the owner
or pledgee of Notes and may otherwise deal with the Company, any Guarantor or
any Affiliate of the Company with the same rights it would have if it were not
Trustee. However, in the event that the Trustee acquires any conflicting
interest it must eliminate such conflict within 90 days, apply to the SEC for
permission to continue as trustee or resign. Any Agent may do the same with like
rights and duties. The Trustee is also subject to Sections 7.10 and 7.11 hereof.

Section 7.04    Trustee's Disclaimer.

        The Trustee shall not be responsible for and makes no representation as
to the validity or adequacy of this Indenture or the Notes, it shall not be
accountable for the Company's use of the proceeds from the Notes or any money
paid to the Company or upon the Company's direction under any provision of this
Indenture, it shall not be responsible for the use or application of any money
received by any Paying Agent other than the Trustee, and it shall not be
responsible for any statement or recital herein or any statement in the Notes or
any other document in connection with the sale of the Notes or pursuant to this
Indenture other than its certificate of authentication.

Section 7.05    Notice of Defaults.

        If a Default or Event of Default occurs and is continuing and if it is
known to the Trustee, the Trustee shall mail to Holders of Notes a notice of the
Default or Event of Default within 90 days after it occurs. Except in the case
of a Default or Event of Default in payment of principal of, premium or
Liquidated Damages, if any, or interest on any Note, the Trustee may withhold
the notice if and so long as a committee of its Responsible Officers in good
faith determines that withholding the notice is in the interests of the Holders
of the Notes.

Section 7.06    Reports by Trustee to Holders of the Notes.

        Within 60 days after each May 15 beginning with the May 15 following the
Issue Date, and for so long as Notes remain outstanding, the Trustee shall mail
to the Holders of the Notes a brief report dated as of such reporting date that
complies with TIA Section 313(a) (but if no event described in TIA Section
313(a) has occurred  within the twelve months  preceding the reporting  date, no
report  need  be   transmitted).   The  Trustee   also  shall  comply  with  TIA
Section 313(b)(2) and  Section 313(b)(1).  The Trustee shall also transmit by
mail all reports as required by TIA Section 313(c).

        A copy of each report at the time of its mailing to the Holders of Notes
shall be mailed by the Trustee to the Company and filed by the Trustee with the
SEC and each stock exchange on which the Notes are listed in accordance with TIA
Section 313(d). The Company shall promptly notify the Trustee when the Notes are
listed on any stock exchange.

Section 7.07    Compensation and Indemnity.

        The Company shall pay to the Trustee from time to time reasonable
compensation for its acceptance of this Indenture and services hereunder. The
Trustee's compensation shall not be limited by any law on compensation of a
trustee of an express trust. The Company shall reimburse the Trustee promptly
upon request for all reasonable disbursements, advances and expenses incurred or
made by it in

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addition to the compensation for its services. Such expenses shall include the
reasonable compensation, disbursements and expenses of the Trustee's agents and
counsel.

        The Company and the Guarantors shall indemnify the Trustee against any
and all losses, liabilities or expenses incurred by it arising out of or in
connection with the acceptance or administration of its duties under this
Indenture, including the costs and expenses of enforcing this Indenture against
the Company and the Guarantors (including this Section 7.07) and defending
itself against any claim (whether asserted by the Company, any Guarantor or any
Holder or any other Person) or liability in connection with the exercise or
performance of any of its powers or duties hereunder, except to the extent any
such loss, liability or expense may be attributable to its negligence, bad faith
or willful misconduct. The Trustee shall notify the Company promptly of any
claim for which it may seek indemnity. Failure by the Trustee to so notify the
Company shall not relieve the Company or the Guarantors of their obligations
hereunder. The Company or such Guarantor shall defend the claim and the Trustee
shall cooperate in the defense. The Trustee may have separate counsel and the
Company shall pay the reasonable fees and expenses of such counsel. The Company
need not pay for any settlement made without its consent, which consent shall
not be unreasonably withheld.

        The obligations of the Company and the Guarantors under this Section
7.07 shall survive the satisfaction and discharge of this Indenture.

        To secure the Company's payment obligations in this Section 7.07, the
Trustee shall have a Lien prior to the Notes on all money or property held or
collected by the Trustee, except that held in trust to pay principal and
interest on particular Notes. Such Lien shall survive the satisfaction and
discharge of this Indenture.

        When the Trustee incurs expenses or renders services after an Event of
Default specified in Section 6.01(k) or (l) hereof occurs, the expenses and the
compensation for the services (including the fees and expenses of its agents and
counsel) are intended to constitute expenses of administration under any
Bankruptcy Law.

        The Trustee shall comply with the provisions of TIA Section 313(b)(2) to
the extent applicable.

Section 7.08    Replacement of Trustee.

        A resignation or removal of the Trustee and appointment of a successor
Trustee shall become effective only upon the successor Trustee's acceptance of
appointment as provided in this Section 7.08.

        The Trustee may resign in writing at any time and be discharged from the
trust hereby created by so notifying the Company. The Holders of Notes of a
majority in principal amount of the then outstanding Notes may remove the
Trustee by so notifying the Trustee and the Company in writing. The Company may
remove the Trustee if:

        (a)     the Trustee fails to comply with Section 7.10 hereof;

        (b)     the Trustee is adjudged a bankrupt or an insolvent or an order
for relief is entered with respect to the Trustee under any Bankruptcy Law;

        (c)     a Custodian or public officer takes charge of the Trustee or its
property; or

        (d)     the Trustee becomes incapable of acting.

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        If the Trustee resigns or is removed or if a vacancy exists in the
office of Trustee for any reason, the Company shall promptly appoint a successor
Trustee. Within one year after the successor Trustee takes office, the Holders
of a majority in principal amount of the then outstanding Notes may appoint a
successor Trustee to replace the successor Trustee appointed by the Company.

         If a successor Trustee does not take office within 60 days after the
retiring Trustee resigns or is removed, the retiring Trustee, the Company, or
the Holders of Notes of at least 10% in principal amount of the then outstanding
Notes may petition any court of competent jurisdiction for the appointment of a
successor Trustee.

        If the Trustee, after written request by any Holder of a Note who has
been a Holder of a Note for at least six months, fails to comply with Section
7.10 hereof, such Holder of a Note may petition any court of competent
jurisdiction for the removal of the Trustee and the appointment of a successor
Trustee.

        A successor Trustee shall deliver a written acceptance of its
appointment to the retiring Trustee and to the Company. Thereupon, the
resignation or removal of the retiring Trustee shall become effective, and the
successor Trustee shall have all the rights, powers and duties of the Trustee
under this Indenture. The successor Trustee shall mail a notice of its
succession to Holders of the Notes. The retiring Trustee shall promptly transfer
all property held by it as Trustee to the successor Trustee, provided all sums
owing to the Trustee hereunder have been paid and subject to the Lien provided
for in Section 7.07 hereof. Notwithstanding replacement of the Trustee pursuant
to this Section 7.08, the Company's obligations under Section 7.07 hereof shall
continue for the benefit of the retiring Trustee.

Section 7.09    Successor Trustee by Merger, etc.

        If the Trustee consolidates, merges or converts into, or transfers all
or substantially all of its corporate trust business to, another corporation,
the successor corporation without any further act shall be the successor
Trustee. As soon as practicable, the successor Trustee shall mail a notice of
its succession to the Company and the Holders of the Notes.

Section 7.10    Eligibility; Disqualification.

        There shall at all times be a Trustee hereunder that is a corporation
organized and doing business under the laws of the United States of America or
of any state thereof that is authorized under such laws to exercise corporate
trustee power, that is subject to supervision or examination by federal or state
authorities and that has a combined capital and surplus of at least $100 million
as set forth in its most recent published annual report of condition.

        This Indenture shall always have a Trustee who satisfies the
requirements of TIA Section 310(a)(1), (2) and (5). The Trustee is subject to
TIA Section 310(b).  For purposes of this Indenture,  each of the Indenture
dated as of February 9, 1998, between Frontier Oil Corporation and JP Morgan
Chase Bank (formerly Chase Bank of Texas, National Association) relating to
Frontier Oil Corporation's 9 1/8% Senior Notes due 2006, and the Indenture dated
as of November 12, 1999, between Frontier Oil Corporation and JP Morgan Chase
Bank (formerly Chase Bank of Texas, National Association) relating to Frontier
Oil Corporation's 11 3/4% Senior Notes due 2009 shall be excluded from the
operation of TIA Section 310(b).

Section 7.11    Preferential Collection of Claims Against Company.

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

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                                   ARTICLE 8.
                    LEGAL DEFEASANCE AND COVENANT DEFEASANCE

Section 8.01    Option to Effect Legal Defeasance or Covenant Defeasance.

        Following the consummation of the Escrow Corp. Merger, the Company may,
at the option of its Board of Directors evidenced by a resolution set forth in
an Officers' Certificate, at any time, exercise its rights under either Section
8.02 or 8.03 hereof with respect to all outstanding Notes upon compliance with
the conditions set forth below in this Article 8.

Section 8.02    Legal Defeasance and Discharge.

        Upon the Company's exercise under Section 8.01 hereof of the option
applicable to this Section 8.02, the Company shall, subject to the satisfaction
of the conditions set forth in Section 8.04 hereof, be deemed to have discharged
its obligations with respect to all outstanding Notes, and each Guarantor shall
be deemed to have discharged its obligations with respect to its Guarantee, on
the date the conditions set forth in Section 8.04 below are satisfied
(hereinafter, "Legal Defeasance"). For this purpose, Legal Defeasance means that
the Company shall be deemed to have paid and discharged the entire Indebtedness
represented by the outstanding Notes, and each Guarantor shall be deemed to have
paid and discharged its Guarantee (which in each case shall thereafter be deemed
to be "outstanding" only for the purposes of Section 8.05 hereof and the other
Sections of this Indenture referred to in (a) and (b) below) and to have
satisfied all its other obligations under such Notes or Guarantee and this
Indenture (and the Trustee, on demand of and at the expense of the Company,
shall execute proper instruments acknowledging the same), except for the
following provisions which shall survive until otherwise terminated or
discharged hereunder: (a) the rights of Holders of outstanding Notes to receive
solely from the trust fund described in Section 8.04 hereof, and as more fully
set forth in such Section, payments in respect of the principal of and premium,
if any, interest and Liquidated Damages, if any, on such Notes when such
payments are due, (b) the Company's obligations with respect to such Notes under
Article 2 and Section 4.02 hereof, (c) the rights, powers, trusts, duties and
immunities of the Trustee hereunder and the Company's obligations in connection
therewith and (d) this Article 8. Subject to compliance with this Article 8, the
Company may exercise its option under this Section 8.02 notwithstanding the
prior exercise of its option under Section 8.03 hereof.

Section 8.03    Covenant Defeasance.

        Upon the Company's exercise under Section 8.01 hereof of the option
applicable to this Section 8.03, the Company and each Guarantor shall, subject
to the satisfaction of the conditions set forth in Section 8.04 hereof, be
released from its obligations contained in Sections 4.07, 4.08, 4.09, 4.10,
4.11, 4.12, 4.13, 4.15, 4.16, 4.17, 4.18, 4.19, 4.20 and 5.01 hereof on and
after the date the conditions set forth below are satisfied (hereinafter,
"Covenant Defeasance"), and the Notes shall thereafter be deemed not
"outstanding" for the purposes of any direction, waiver, consent or declaration
or act of Holders (and the consequences of any thereof) in connection with such
covenants, but shall continue to be deemed "outstanding" for all other purposes
hereunder (it being understood that such Notes shall not be deemed outstanding
for accounting purposes). For this purpose, Covenant Defeasance means that, with
respect to the outstanding Notes and Guarantees, the Company and any Guarantor
may omit to comply with and shall have no liability in respect of any term,
condition or limitation set forth in any such covenant, whether directly or
indirectly, by reason of any reference elsewhere herein to any such covenant or
by reason of any reference in any such covenant to any other provision herein or
in any other document and such omission to comply shall not constitute a Default
or an Event of Default under Section 6.01 hereof, but, except as specified
above, the remainder of this Indenture and such Notes shall be unaffected
thereby. In addition, upon the Company's exercise under Section 8.01 hereof of
the option applicable to this

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Section 8.03 hereof, subject to the satisfaction of the conditions set forth in
Section 8.04 hereof, Sections 6.01(f) through 6.01(h) hereof shall not
constitute Events of Default.

Section 8.04    Conditions to Legal or Covenant Defeasance.

        In order to exercise either Legal Defeasance or Covenant Defeasance:

        (a)     the Escrow Corp. Merger must have been consummated;

        (b)     the Company must irrevocably deposit with the Trustee, in trust,
for the benefit of the Holders, cash in United States dollars, non-callable
Government Securities, or a combination thereof, in such amounts as will be
sufficient, in the opinion of a nationally recognized firm of independent public
accountants, to pay the principal of and premium, if any, interest and
Liquidated Damages, if any, on the outstanding Notes on the stated date for
payment thereof or on the applicable redemption date, as the case may be, and
the Company must specify whether the Notes are being defeased to maturity or to
a particular redemption date;

        (c)     in the case of an election under Section 8.02 hereof, the
Company shall have delivered to the Trustee an Opinion of Counsel in the United
States reasonably acceptable to the Trustee confirming that (A) the Company has
received from, or there has been published by, the Internal Revenue Service a
ruling or (B) since the Issue Date, there has been a change in the applicable
federal income tax law, in either case to the effect that, and based thereon
such Opinion of Counsel shall confirm that, the Holders of the outstanding Notes
will not recognize income, gain or loss for federal income tax purposes as a
result of such Legal Defeasance and will be subject to federal income tax on the
same amounts, in the same manner and at the same times as would have been the
case if such Legal Defeasance had not occurred;

        (d)     in the case of an election under Section 8.03 hereof, the
Company shall have delivered to the Trustee an Opinion of Counsel in the United
States reasonably acceptable to the Trustee confirming that the Holders of the
outstanding Notes will not recognize income, gain or loss for federal income tax
purposes as a result of such Covenant Defeasance and will be subject to federal
income tax on the same amounts, in the same manner and at the same times as
would have been the case if such Covenant Defeasance had not occurred;

        (e)     no Default or Event of Default shall have occurred and be
continuing on the date of such deposit (other than a Default or Event of Default
resulting from the borrowing of funds to be applied to such deposit);

        (f)     such Legal Defeasance or Covenant Defeasance shall not result in
a breach or violation of, or constitute a default under, any material agreement
or instrument (other than this Indenture) to which the Company or any of its
Restricted Subsidiaries or Parent is a party or by which the Company or any of
its Restricted Subsidiaries or Parent is bound;

        (g)     the Company shall have delivered to the Trustee an Opinion of
Counsel (which may be based on such solvency certificates or solvency opinions
as counsel deems necessary or appropriate) to the effect that the trust funds
will not be subject to the effect of any applicable bankruptcy, insolvency,
reorganization or similar laws affecting creditors' rights generally;

        (h)     the Company shall have delivered to the Trustee an Officers'
Certificate stating that the deposit was not made by the Company with the intent
of preferring the Holders of Notes over any other creditors of the Company or
with the intent of defeating, hindering, delaying or defrauding creditors of the
Company or others; and

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        (i)     the Company shall have delivered to the Trustee an Officers'
Certificate and an Opinion of Counsel, each stating that all conditions
precedent provided for or relating to the Legal Defeasance or the Covenant
Defeasance have been complied with.

Section 8.05    Deposited Money and Government Securities to be Held in Trust;
Other Miscellaneous Provisions.

        Subject to Section 8.06 hereof, all money and non-callable Government
Securities (including the proceeds thereof) deposited with the Trustee (or any
other qualifying trustee, collectively for purposes of this Section 8.05, the
"Trustee") pursuant to Section 8.04 hereof in respect of the outstanding Notes
shall be held in trust and applied by the Trustee, in accordance with the
provisions of such Notes and this Indenture, to the payment, either directly or
through any Paying Agent (including the Company acting as Paying Agent) as the
Trustee may determine, to the Holders of such Notes of all sums due and to
become due thereon in respect of principal, premium and Liquidated Damages, if
any, and interest, but such money need not be segregated from other funds except
to the extent required by law.

        The Company shall pay and indemnify the Trustee against any tax, fee or
other charge imposed on or assessed against the cash or non-callable Government
Securities deposited pursuant to Section 8.04 hereof or the principal and
interest received in respect thereof other than any such tax, fee or other
charge which by law is for the account of the Holders of the outstanding Notes.

        Anything in this Article 8 to the contrary notwithstanding, the Trustee
shall deliver or pay to the Company from time to time upon the request of the
Company any money or non-callable Government Securities held by it as provided
in Section 8.04 hereof which, in the opinion of a nationally recognized firm of
independent public accountants expressed in a written certification thereof
delivered to the Trustee (which may be the opinion delivered under Section
8.04(a) hereof), are in excess of the amount thereof that would then be required
to be deposited to effect an equivalent Legal Defeasance or Covenant Defeasance.

Section 8.06    Repayment to Company.

        Subject to applicable escheat and abandoned property laws, 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, premium or Liquidated Damages, if
any, or interest on any Note and remaining unclaimed for two years after such
principal, and premium or Liquidated Damages, if any, or interest has become due
and payable shall be paid to the Company on its request or (if then held by the
Company) shall be discharged from such trust; and the Holder of such Note shall
thereafter, as a secured 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 the New York Times and The Wall Street Journal (national
edition), 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
notification or publication, any unclaimed balance of such money then remaining
will be repaid to the Company.

Section 8.07    Reinstatement.

        If the Trustee or Paying Agent is unable to apply any United States
dollars or non-callable Government Securities in accordance with Section 8.05
hereof, by reason of any order or judgment of any court or governmental
authority enjoining, restraining or otherwise prohibiting such application, then
the Company's obligations under this Indenture and the Notes and each
Guarantor's obligations under this

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Indenture and its Guarantee shall be revived and reinstated as though no deposit
had occurred pursuant to Section 8.02 or 8.03 hereof until such time as the
Trustee or Paying Agent is permitted to apply all such money in accordance with
Section 8.05 hereof; provided, however, that, if the Company makes any payment
of principal of, premium or Liquidated Damages, if any, or interest on any Note
following the reinstatement of its obligations, the Company shall be subrogated
to the rights of the Holders of such Notes to receive such payment from the
money held by the Trustee or Paying Agent.

                                   ARTICLE 9.
                        AMENDMENT, SUPPLEMENT AND WAIVER

Section 9.01    Without Consent of Holders of Notes.

        Notwithstanding Section 9.02 of this Indenture, the Company, the
Guarantors and the Trustee may amend or supplement this Indenture, the Notes and
the Guarantees without the consent of any Holder of a Note:

        (a)     to cure any ambiguity, defect or inconsistency;

        (b)     to provide for uncertificated Notes in addition to or in place
of certificated Notes or to alter the provisions of Article 2 hereof (including
the related definitions) in a manner that does not materially adversely affect
any Holder;

        (c)     to provide for the assumption of the Company's or a Guarantor's
obligations to the Holders of the Notes pursuant to Article 5 or Article 10
hereof;

        (d)     to secure the Notes pursuant to the requirements of Section 4.12
or otherwise;

        (e)     to make any change that would provide any additional rights or
benefits to the Holders of the Notes or that does not adversely affect the legal
rights hereunder of any Holder of the Note;

        (f)     to comply with Article 10 hereof;

        (g)     to add any Guarantor or to release any Subsidiary Guarantor from
its Subsidiary Guarantee, in each as provided in this Indenture;

        (h)     to conform the text of this Indenture, the Guarantees or the
Notes to any provision found under the heading "Description of the Notes" in the
Company's Offering Memorandum relating to the Notes to the extent that such
provision was intended to be a verbatim recitation of a provision of this
Indenture, the Guarantees or the Notes, as applicable; or

        (i)     to comply with requirements of the SEC in order to effect or
maintain the qualification of this Indenture under the TIA.

        Upon the request of the Company accompanied by a resolution of its Board
of Directors authorizing the execution of any such amended or supplemental
indenture, and upon receipt by the Trustee of the documents described in Section
7.02 hereof, the Trustee shall join with the Company and the Guarantors in the
execution of any amended or supplemental indenture authorized or permitted by
the terms of this Indenture and to make any further appropriate agreements and
stipulations that may be therein contained, but the Trustee shall not be
obligated to enter into such amended or supplemental Indenture that affects its
own rights, duties or immunities under this Indenture or otherwise.

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<PAGE>

Section 9.02    With Consent of Holders of Notes.

        Except as provided below in this Section 9.02, the Company, the
Guarantors and the Trustee may amend or supplement this Indenture and the Notes
and the Guarantees may be amended or supplemented with the consent of the
Holders of at least a majority in principal amount of the Notes then
outstanding, voting as a single class (including, without limitation, consents
obtained in connection with a purchase of, or tender offer or exchange offer
for, the Notes), and, subject to Sections 6.04 and 6.07 hereof, any existing
Default or Event of Default (other than a Default or Event of Default in the
payment of the principal of, premium or Liquidated Damages, if any, or interest
on the Notes, except a payment default resulting from an acceleration that has
been rescinded) or compliance with any provision of this Indenture, the Notes or
the Guarantees may be waived with the consent of the Holders of a majority in
principal amount of the then outstanding Notes voting as a single class
(including consents obtained in connection with a tender offer or exchange offer
for the Notes).

        Upon the request of the Company accompanied by a resolution of its Board
of Directors authorizing the execution of any such amended or supplemental
indenture, and upon the filing with the Trustee of evidence satisfactory to the
Trustee of the consent of the Holders of Notes as aforesaid, and upon receipt by
the Trustee of the documents described in Section 9.06 hereof, the Trustee shall
join with the Company and the Guarantors in the execution of such amended or
supplemental indenture unless such amended or 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 amended or supplemental indenture.

        It shall not be necessary for the consent of the Holders of Notes under
this Section 9.02 to approve the particular form of any proposed amendment,
supplement or waiver, but it shall be sufficient if such consent approves the
substance thereof.

        After an amendment, supplement or waiver under this Section becomes
effective, the Company shall mail to the Holders of Notes affected thereby a
notice briefly describing the amendment, supplement or waiver. Any failure of
the Company to mail such notice, or any defect therein, shall not, however, in
any way impair or affect the validity of any such amended or supplemental
Indenture or waiver. Subject to Sections 6.04 and 6.07 hereof, the Holders of a
majority in aggregate principal amount of the Notes then outstanding, voting as
a single class, may waive compliance in a particular instance by the Company or
any Guarantor with any provision of this Indenture, the Notes or the Guarantees,
as applicable. However, without the consent of each Holder affected, an
amendment, supplement or waiver under this Section 9.02 may not (with respect to
any Notes held by a non-consenting Holder):

        (a)     reduce the principal amount of Notes whose Holders must consent
to an amendment, supplement or waiver;

        (b)     reduce the principal of or change the fixed maturity of any Note
or alter or waive any of the provisions with respect to the redemption of the
Notes (other than the provisions relating to Sections 3.09, 4.10 and 4.15
hereof);

        (c)     reduce the rate of or change the time for payment of interest,
including default interest, on any Note;

        (d)     waive a Default or Event of Default in the payment of principal
of or premium, if any, interest or Liquidated Damages, if any, on the Notes
(except a rescission of acceleration of the Notes by the Holders of at least a
majority in aggregate principal amount of the then outstanding Notes and a
waiver of the payment default that resulted from such acceleration);

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

        (f)     make any change in the provisions of this Indenture relating to
waivers of past Defaults or Events of Default or the rights of Holders of Notes
to receive payments of principal of or premium, if any, interest or Liquidated
Damages, if any, on the Notes (except as permitted in clause (g) below);

        (g)     waive a redemption payment with respect to any Note (other than
a payment required by Sections 4.10 or 4.15 hereof);

        (h)     make any change in the ranking of the Notes or the Guarantees
relative to other Indebtedness of the Company or the Guarantor, as applicable,
in either case in a manner adverse to the Holders of Notes;

        (i)     release any Subsidiary Guarantor from any of its obligations
under its Subsidiary Guarantee or this Indenture, except in accordance with the
terms of this Indenture; or

        (j)     make any change in the foregoing amendment, supplement and
waiver provisions.

Section 9.03    Compliance with Trust Indenture Act.

        Every amendment or supplement to this Indenture or the Notes shall be
set forth in a amended or supplemental Indenture that complies with the TIA as
then in effect.

Section 9.04    Revocation and Effect of Consents.

        Until an amendment, supplement or waiver becomes effective, a consent to
it by a Holder of a Note is a continuing consent by the Holder of a Note and
every subsequent Holder of a Note or portion of a Note that evidences the same
debt as the consenting Holder's Note, even if notation of the consent is not
made on any Note. However, any such Holder of a Note or subsequent Holder of a
Note may revoke the consent as to its Note if the Trustee receives written
notice of revocation before the date the waiver, supplement or amendment becomes
effective. An amendment, supplement or waiver becomes effective in accordance
with its terms and thereafter binds every Holder.

Section 9.05    Notation on or Exchange of Notes.

        The Trustee may place an appropriate notation about an amendment,
supplement or waiver on any Note thereafter authenticated. The Company in
exchange for all Notes may issue, and the Trustee shall, upon receipt of an
Authentication Order, authenticate, new Notes that reflect the amendment,
supplement or waiver.

        Failure to make the appropriate notation or issue a new Note shall not
affect the validity and effect of such amendment, supplement or waiver.

Section 9.06    Trustee to Sign Amendments, etc.

        The Trustee shall sign any amended or supplemental indenture authorized
pursuant to this Article 9 if the amendment or supplement does not adversely
affect the rights, duties, liabilities or immunities of the Trustee. The Company
may not sign an amendment or supplemental indenture until the Board of Directors
approves it. In executing any amended or supplemental indenture, the Trustee
shall be entitled to receive and (subject to Section 7.01 hereof) shall be fully
protected in relying upon, in addition to the documents required by Section
12.04 hereof, an Officers' Certificate and an Opinion of Counsel stating

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that the execution of such amended or supplemental indenture is authorized or
permitted by this Indenture.

                                   ARTICLE 10.
                               GUARANTEES OF NOTES

Section 10.01   Guarantees.

        (a)     Subject to Section 10.06 hereof, each of the Guarantors, jointly
and severally, unconditionally guarantees to each Holder of a Note authenticated
and delivered by the Trustee and to the Trustee and its successors and assigns,
irrespective of the validity and enforceability of this Indenture, the Notes
held thereby and the Obligations of the Company hereunder and thereunder, that:

                (i)     the principal of and premium, interest and Liquidated
        Damages, if any, on the Notes will be promptly paid in full when due,
        subject to any applicable grace period, whether at maturity, by
        acceleration, redemption or otherwise, and interest on the overdue
        principal, premium, (to the extent permitted by law) interest and
        Liquidated Damages, if any, on the Notes, and all other Obligations of
        the Company to the Holders or the Trustee hereunder or thereunder will
        be promptly paid in full and performed, all in accordance with the terms
        hereof and thereof; and

                (ii)    in case of any extension of time of payment or renewal
        of any Notes or any of such other Obligations, the same will be promptly
        paid in full when due or performed in accordance with the terms of the
        extension or renewal, subject to any applicable grace period, whether at
        stated maturity, by acceleration, redemption or otherwise.

        Failing payment when so due of any amount so guaranteed or any
performance so guaranteed for whatever reason the Guarantors will be jointly and
severally obligated to pay the same immediately. An Event of Default under this
Indenture or the Notes shall constitute an event of default under the
Guarantees, and shall entitle the Holders to accelerate the obligations of the
Guarantors hereunder in the same manner and to the same extent as the
Obligations of the Company. Each Guarantor agrees that this is a guarantee of
payment and not a guarantee of collection.

        (b)     The Guarantors agree that their obligations hereunder shall be
unconditional, irrespective of the validity, regularity or enforceability of the
Notes or this Indenture, the absence of any action to enforce the same, any
waiver or consent by any Holder 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 (other than complete performance) which might
otherwise constitute a legal or equitable discharge or defense of a Guarantor.
Each Guarantor further, to the extent permitted by law, waives diligence,
presentment, demand of payment, 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, protest, notice and all demands whatsoever and covenants
that this Guarantee will not be discharged except by complete performance of the
Obligations contained in the Notes and this Indenture.

        (c)     If any Holder or the Trustee is required by any court or
otherwise to return to the Company, the Guarantors, or any custodian, trustee or
other similar official acting in relation to either the Company or the
Guarantors, any amount paid by the Company or any Guarantor to the Trustee or
such Holder, the Guarantees, to the extent theretofore discharged, shall be
reinstated in full force and effect. Each Guarantor agrees that it shall not be
entitled to, and waives, any right of subrogation in relation to the Holders in
respect of any Obligations guaranteed hereby until payment in full of all
Obligations guaranteed hereby. Each Guarantor further agrees that, as between
the Guarantors, on the one hand, and

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the Holders and the Trustee, on the other hand, (a) the maturity of the
Obligations guaranteed hereby may be accelerated as provided in Article 6 hereof
for the purposes of its Guarantee, notwithstanding any stay, injunction or other
prohibition preventing such acceleration in respect of the Obligations
guaranteed thereby, and (b) in the event of any declaration of acceleration of
such Obligations as provided in Article 6 hereof, such Obligations (whether or
not due and payable) shall forthwith become due and payable by the Guarantor for
the purpose of its Guarantee. The Guarantors shall have the right to seek
contribution from any non-paying Guarantor so long as the exercise of such right
does not impair the rights of the Holders under the Guarantees.

Section 10.02   Execution and Delivery of Guarantee.

        To evidence its Guarantee set forth in Section 10.01 hereof, each
Guarantor agrees that a notation of such Guarantee substantially in the form of
Exhibit E hereto shall be endorsed by manual or facsimile signature by an
Officer of such Guarantor on each Note authenticated and delivered by the
Trustee and that this Indenture shall be executed on behalf of such Guarantor by
an Officer of such Guarantor.

        To the extent required by the provisions of Section 4.13 hereof, the
Company shall cause each of its Restricted Subsidiaries to execute a Guarantee
substantially in the form of Exhibit E. Such Guarantee shall be accompanied by a
supplemental indenture substantially in the form of Exhibit E, along with the
Opinion of Counsel and Officers' Certificate required under Section 9.06 of this
Indenture; provided, however, that any Subsidiary that has been properly
designated as an Unrestricted Subsidiary in accordance with this Indenture need
not execute a Subsidiary Guarantee for so long as it continues to constitute an
Unrestricted Subsidiary.

        Each Guarantor agrees that its Guarantee set forth in Section 10.01
hereof shall remain in full force and effect notwithstanding any failure to
endorse on each Note a notation of such Guarantee.

        If an Officer whose signature is on this Indenture or the Guarantee no
longer holds that office at the time the Trustee authenticates the Note on which
a Guarantee is endorsed, the Guarantee shall be valid nevertheless.

        The delivery of any Note by the Trustee, after the authentication
thereof hereunder, shall constitute due delivery of the Guarantees set forth in
this Indenture on behalf of the Guarantors.

Section 10.03   Guarantors May Consolidate, etc., on Certain Terms.

        (a)     Except as set forth in Articles 4 and 5 hereof, nothing
contained in this Indenture or in any of the Notes shall prohibit any
consolidation or merger of a Guarantor with or into the Company or another
Guarantor, or will prevent any sale or conveyance of the property of a Guarantor
as an entirety or substantially as an entirety to the Company or a Restricted
Subsidiary of the Company.

        (b)     Except as otherwise provided in Section 10.04 hereof, no
Subsidiary Guarantor shall sell or otherwise dispose of all or substantially all
of its assets to, consolidate with or merge with or into (whether or not such
Guarantor is the surviving Person), another Person (other than the Company or a
Restricted Subsidiary of the Company), whether or not affiliated with such
Guarantor, unless, (i) immediately after giving effect to such transaction, no
Default or Event of Default exists; and (ii) either: (A) subject to Section
10.04 hereof, the Person acquiring the property in any such sale or disposition,
or the Person formed by or surviving any such consolidation or merger, assumes
all of the obligations of the Guarantor under this Indenture, its Subsidiary
Guarantee and the Registration Rights Agreement on the terms set forth herein or
therein pursuant to a supplemental indenture satisfactory to the Trustee; or (B)

                                       68

<PAGE>

the Net Proceeds of such sale or other disposition are applied in accordance
with the applicable provisions of this Indenture, including without limitation
Section 4.10 hereof.

        (c)     From and after such time as Parent executes a supplemental
indenture and a Guarantee, Parent may not sell or otherwise dispose of all or
substantially all of its assets to, or consolidate with or merge with or into
(whether or not Parent is the surviving Person), another Person (other than the
Company or a Restricted Subsidiary of the Company) unless, (i) immediately after
giving effect to such transaction, no Default or Event of Default exists, and
(ii) subject to Section 10.04 hereof, the Person acquiring the property in any
such sale or disposition, or the Person formed by or surviving any such
consolidation or merger, assumes all of the obligations of Parent under this
Indenture, its Guarantee and, if applicable, the Registration Rights Agreement
on the terms set forth herein or therein pursuant to a supplemental indenture
satisfactory to the Trustee.

Section 10.04   Releases Following Sale of Assets.

        In the event of a sale or other disposition of all or substantially all
of the assets or Capital Stock of any Subsidiary Guarantor, by way of merger,
consolidation or otherwise, then such Subsidiary Guarantor (in the event of a
sale or other disposition, by way of such a merger, consolidation or otherwise,
of all of the Capital Stock of such Subsidiary Guarantor) or the Person
acquiring the assets (in the event of a sale or other disposition of all of the
assets of such Subsidiary Guarantor) shall be released and relieved of any
obligations under its Subsidiary Guarantee; provided, however, that the Net
Proceeds from such sale or other disposition are applied in accordance with the
applicable provisions of this Indenture, including without limitation of Section
4.10 hereof; provided, further, that upon such release, the obligations of such
Subsidiary Guarantor in respect of any and all other guarantees of Indebtedness
of the Company or a Guarantor are similarly released. Upon delivery by the
Company to the Trustee of an Officers' Certificate to the effect of the
foregoing, the Trustee shall execute any documents reasonably required in order
to evidence the release of any Subsidiary Guarantor from its obligations under
its Subsidiary Guarantee.

        Any Subsidiary Guarantor not released from its obligations under its
Subsidiary Guarantee shall remain liable for the full amount of principal of and
premium, interest and Liquidated Damages, if any, on the Notes and for the other
Obligations of such Subsidiary Guarantor under this Indenture as provided in
this Article 10.

Section 10.05   Releases Following Designation as an Unrestricted Subsidiary.

        In the event that the Board of the Directors of Company designates a
Subsidiary Guarantor to be an Unrestricted Subsidiary, then such Subsidiary
Guarantor shall be released and relieved of any obligations under its Subsidiary
Guarantee; provided that such designation is conducted in accordance with this
Indenture.

Section 10.06   Limitation on Guarantor Liability.

        Each Guarantor, and by its acceptance of Notes, each Holder, confirms
that it is the intention of all such parties that the Guarantee of such
Guarantor not constitute a fraudulent transfer or conveyance for purposes of
Bankruptcy Law, the Uniform Fraudulent Conveyance Act, the Uniform Fraudulent
Transfer act or any similar federal or state law to the extent applicable to any
Guarantee. To effectuate the foregoing intention, the Trustee, the Holders and
the Guarantors irrevocably agree that the obligations of such Guarantor will be
limited to the maximum amount that will, after giving effect to such maximum
amount and all other contingent and fixed liabilities of such Guarantor that are
relevant under such laws, and after giving effect to any collections from,
rights to receive contribution from or payments made by or

                                       69

<PAGE>

on behalf of any other Guarantor in respect of the obligations of such other
Guarantor under this Article 10, result in the obligations of such Guarantor
under its Guarantee not constituting a fraudulent transfer or conveyance.

Section 10.07   "Trustee" to Include Paying Agent.

        In case at any time any Paying Agent other than the Trustee shall have
been appointed by the Company and be then acting hereunder, the term "Trustee"
as used in this Article 10 shall in each case (unless the context shall
otherwise require) be construed as extending to and including such Paying Agent
within its meaning as fully and for all intents and purposes as if such Paying
Agent were named in this Article 10 in place of the Trustee.

                                   ARTICLE 11.
                           SATISFACTION AND DISCHARGE

Section 11.01   Satisfaction and Discharge.

        This Indenture will be discharged and will cease to be of further effect
as to all Notes issued hereunder, when:

                (1)     either:

                        (a)     all Notes that have been authenticated (except
        lost, stolen or destroyed Notes that have been replaced or paid and
        Notes for whose payment money has theretofore been deposited in trust
        and thereafter repaid to the Company) have been delivered to the Trustee
        for cancellation; or

                        (b)     all Notes that have not been delivered to the
        Trustee for cancellation have become due and payable by reason of the
        mailing of a notice of redemption or otherwise or will become due and
        payable within one year and the Company or any Guarantor has irrevocably
        deposited or caused to be deposited with the Trustee as trust funds in
        trust solely for the benefit of the Holders, cash in U.S. dollars, non-
        callable Government Securities, or a combination thereof, in such
        amounts as will be sufficient without consideration of any reinvestment
        of interest, to pay and discharge the entire indebtedness on the Notes
        not delivered to the Trustee for cancellation for principal, premium and
        Liquidated Damages, if any, and accrued interest to the date of maturity
        or redemption;

                (2)     no Default or Event of Default has occurred and is
        continuing on the date of such deposit or will occur as a result of such
        deposit and such deposit will not result in a breach or violation of, or
        constitute a default under, any other instrument to which the Company or
        any Guarantor is a party or by which the Company or any Guarantor is
        bound;

                (3)     the Company or any Guarantor has paid or caused to be
        paid all sums payable by it under this Indenture; and

                (4)     the Company has delivered irrevocable instructions to
        the Trustee under this Indenture to apply the deposited money toward the
        payment of the Notes at maturity or the redemption date, as the case may
        be.

In addition, the Company must deliver an Officers' Certificate and an Opinion of
Counsel to the Trustee stating that all conditions precedent to satisfaction and
discharge have been satisfied.

                                       70

<PAGE>

        Notwithstanding the satisfaction and discharge of this Indenture, if
money has been deposited with the Trustee pursuant to subclause (b) of clause
(1) of this Section, the provisions of Section 11.02 and Section 8.06 will
survive. In addition, nothing in this Section 11.01 will be deemed to discharge
those provisions of Section 7.07 hereof, that, by their terms, survive the
satisfaction and discharge of this Indenture.

Section 11.02   Application of Trust Money.

        Subject to the provisions of Section 8.06, all money deposited with the
Trustee pursuant to Section 11.01 shall be held in trust and applied by it, in
accordance with the provisions of the Notes and this Indenture, to the payment,
either directly or through any 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.

        If the Trustee or Paying Agent is unable to apply any money or
Government Securities in accordance with Section 11.01 by reason of any legal
proceeding or by reason of any order or judgment of any court or governmental
authority enjoining, restraining or otherwise prohibiting such application, the
Company's and any Guarantor's obligations under this Indenture and the Notes
shall be revived and reinstated as though no deposit had occurred pursuant to
Section 11.01; provided that if the Company has made any payment of principal
of, premium, if any, or interest on any Notes because of the reinstatement of
its obligations, the Company shall be subrogated to the rights of the Holders of
such Notes to receive such payment from the money or Government Securities held
by the Trustee or Paying Agent.

                                   ARTICLE 12.
                                  MISCELLANEOUS

Section 12.01   Trust Indenture Act Controls.

        If any provision of this Indenture limits, qualifies or conflicts with
the duties imposed by TIA Section 318(c), the imposed duties shall control.

Section 12.02   Notices.

        Any notice or communication by the Company, any Guarantor or the Trustee
to the others is duly given if in writing (in the English language) and
delivered in person or mailed by first class mail (registered or certified,
return receipt requested), telecopier or overnight air courier guaranteeing next
day delivery, to the others' address:

        If to the Company or any Guarantor:

                Frontier Escrow Corporation
                10000 Memorial Drive, Suite 600
                Houston, Texas 77024-3411
                Attention: Julie H. Edwards
                Telecopier No.: (713) 688-0616

                                       71

<PAGE>

        With a copy to:

                Andrews & Kurth L.L.P.
                4200 Chase Tower
                600 Travis Street
                Houston, Texas 77002
                Attention: Robert V. Jewell
                Telecopier No.: (713) 220-4200

        If to the Trustee:

                (1)     For payment, registration, transfer and exchange of the
                        Notes:

                        By Hand:

                        Wells Fargo Bank, N.A.
                        55 Water Street
                        Ground Level - Jeanette Park Entrance
                        New York, NY 10041
                        Attention: Doreen Benson
                        Telephone No.: (212) 855-2460

                        By Mail:

                        Wells Fargo Bank, N.A.
                        55 Water Street
                        Ground Level - Jeanette Park Entrance
                        New York, NY 10041
                        Attention: Doreen Benson
                        Telephone No.: (212) 855-2460

                (2)     For all other communications relating to the Notes:

                        Wells Fargo Bank, N.A.
                        505 Main Street, Suite 301
                        Fort Worth, TX 76102
                        Attention: Melissa A. Scott
                        Telephone No.: (817) 335-7065
                        Telecopier No.: (817) 885-8650

        If to the Paying Agent:

                        Wells Fargo Bank, N.A.
                        55 Water Street
                        Ground Level - Jeanette Park Entrance
                        New York, NY 10041
                        Attention: Doreen Benson
                        Telephone No.: (212) 855-2460

                                       72

<PAGE>

        With a copy to:

                        Wells Fargo Bank, N.A.
                        505 Main Street, Suite 301
                        Fort Worth, TX 76102
                        Attention: Melissa A. Scott
                        Telephone No.: (817) 335-7065
                        Telecopier No.: (817) 885-8650

        The Company, any of the Guarantors or the Trustee, by notice to the
others may designate additional or different addresses for subsequent notices or
communications.

        All notices and communications (other than those sent to Holders) shall
be deemed to have been duly given: at the time delivered by hand, if personally
delivered; five Business Days after being deposited in the mail, postage
prepaid, if mailed; when answered back, if telexed; when receipt acknowledged,
if telecopied; and the next Business Day after timely delivery to the courier,
if sent by overnight air courier guaranteeing next day delivery.

        Any notice or communication to a Holder shall be mailed by first class
mail, certified or registered, return receipt requested, or by overnight air
courier guaranteeing next day delivery to its address shown on the register kept
by the Registrar. Any notice or communication shall also be so mailed to any
Person described in TIA Section 313(c), to the extent required by the TIA.
Failure to mail a notice or communication to a Holder or any defect in it shall
not affect its sufficiency with respect to other Holders.

        If a notice or communication is mailed in the manner provided above
within the time prescribed, it is duly given, whether or not the addressee
receives it.

        If the Company mails a notice or communication to Holders, it shall mail
a copy to the Trustee and each Agent at the same time.

Section 12.03   Communication by Holders of Notes with Other Holders of Notes.

        Holders may communicate pursuant to TIA Section 312(b) with other
Holders with respect to their rights under this Indenture or the Notes. The
Company, the Trustee, the Registrar and anyone else shall have the protection of
TIA Section312(c).

Section 12.04   Certificate and Opinion as to Conditions Precedent.

        Upon any request or application by the Company to the Trustee to take
any action under this Indenture, the Company shall furnish to the Trustee:

        (a)     an Officers' Certificate in form and substance reasonably
satisfactory to the Trustee (which shall include the statements set forth in
Section 12.05 hereof) stating that, in the opinion of the signers, all
conditions precedent and covenants, if any, provided for in this Indenture
relating to the proposed action have been satisfied; and

        (b)     an Opinion of Counsel in form and substance reasonably
satisfactory to the Trustee (which shall include the statements set forth in
Section 12.05 hereof) stating that, in the opinion of such counsel, all such
conditions precedent and covenants have been satisfied.

                                       73

<PAGE>

Section 12.05   Statements Required in Certificate or Opinion.

        Each certificate or opinion with respect to compliance with a condition
or covenant provided for in this Indenture (other than a certificate provided
pursuant to TIA Section 314(a)(4)) shall comply with the provisions of TIA
Section 314(e) and shall include:

        (a)     a statement that the Person making such certificate or opinion
has read such covenant or condition;

        (b)     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;

        (c)     a statement that, in the opinion of such Person, he or she has
made such examination or investigation as is necessary to enable him or her to
express an informed opinion as to whether or not such covenant or condition has
been satisfied; and

        (d)     a statement as to whether or not, in the opinion of such Person,
such condition or covenant has been satisfied.

Section 12.06   Rules by Trustee and Agents.

        The Trustee may make reasonable rules for action by or at a meeting of
Holders. The Registrar or Paying Agent may make reasonable rules and set
reasonable requirements for its functions.

Section 12.07   No Personal Liability of Directors, Officers, Employees and
                Stockholders.

        No past, present or future director, officer, employee, incorporator or
stockholder of the Company or any Guarantor, as such, shall have any liability
for any obligations of the Company or any Guarantor under the Notes, the
Guarantees, this Indenture or for any claim based on, in respect of, or by
reason of, such obligations or their creation. Each Holder by accepting a Note
waives and releases all such liability. The waiver and release are part of the
consideration for issuance of the Notes. The waiver may not be effective to
waive liabilities under the federal securities laws.

Section 12.08   Governing Law.

        THE LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED TO CONSTRUE
AND ENFORCE THIS INDENTURE, THE NOTES AND THE GUARANTEES WITHOUT GIVING EFFECT
TO APPLICABLE PRINCIPLES OR CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION
OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

Section 12.09   No Adverse Interpretation of Other Agreements.

        This Indenture may not be used to interpret any other indenture, loan or
debt agreement of the Company or its Restricted Subsidiaries or of any other
Person. Any such indenture, loan or debt agreement may not be used to interpret
this Indenture.

Section 12.10   Successors.

        All agreements of the Company in this Indenture and the Notes shall bind
its successors. All agreements of the Trustee in this Indenture shall bind its
successors. All agreements of each Guarantor in

                                       74

<PAGE>

its Guarantee and this Indenture shall bind its successors, except as otherwise
provided in Sections 10.04 and 10.05.

Section 12.11   Severability.

        In case any provision in this Indenture or in the Notes 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 12.12   Counterpart Originals.

        The parties may sign any number of copies of this Indenture. Each signed
copy shall be an original, but all of them together represent the same
agreement.

Section 12.13   Table of Contents, Headings, etc.

        The Table of Contents, Cross-Reference Table and Headings of the
Articles and Sections of this Indenture have been inserted for convenience of
reference only, are not to be considered a part of this Indenture and shall in
no way modify or restrict any of the terms or provisions hereof.

                         [Signatures on following page]

                                       75

<PAGE>

                                         SIGNATURES

                                         FRONTIER ESCROW CORPORATION

                                         By: /s/ Julie H. Edwards
                                             -----------------------------------
                                             Name:  Julie H. Edwards
                                             Title: Executive Vice President--
                                                    Finance & Administration and
                                                    Chief Financial Officer

                                         WELLS FARGO BANK, N.A., as Trustee

                                         By: /s/ Frank McDonald
                                             -----------------------------------
                                             Name: Frank McDonald
                                             Title: Vice President

<PAGE>

                                                                     EXHIBIT A-1

                                 (Face of Note)

               8.000% Senior Notes due 2013, [Series A] [Series B]

No. _______________
       CUSIP NO.

                           FRONTIER ESCROW CORPORATION

promises to pay to __________ or registered assigns, the principal sum of
___________ Dollars on April 15, 2013.

                 Interest Payment Dates: April 15 and October 15
                       Record Dates: April 1 and October 1

                                         FRONTIER ESCROW CORPORATION

                                         By:
                                             -----------------------------------
                                             Name:
                                             Title:

Trustee's Certificate of Authentication:

This is one of the Notes referred to in the within-mentioned Indenture.

WELLS FARGO BANK, N.A., as Trustee

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

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

                                      A-1-1

<PAGE>

                                 (Back of Note)

               8.000% SENIOR NOTES DUE 2013, [SERIES A] [SERIES B]

        ["THIS GLOBAL NOTE IS HELD BY THE DEPOSITARY (AS DEFINED IN THE
INDENTURE GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE
BENEFICIAL OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY
CIRCUMSTANCES EXCEPT THAT (I) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS MAY
BE REQUIRED PURSUANT TO SECTION 2.06 OF THE INDENTURE, (II) THIS GLOBAL NOTE MAY
BE EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 2.06 OF THE INDENTURE,
(III) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE FOR CANCELLATION PURSUANT
TO SECTION 2.11 OF THE INDENTURE AND (IV) THIS GLOBAL NOTE MAY BE TRANSFERRED TO
A SUCCESSOR DEPOSITARY WITH THE PRIOR WRITTEN CONSENT OF THE COMPANY."]/1/

        ["THE SECURITY (OR ITS PREDECESSOR) EVIDENCED HEREBY WAS ORIGINALLY
ISSUED IN A TRANSACTION EXEMPT FROM REGISTRATION UNDER SECTION 5 OF THE UNITED
STATES SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), AND THE
SECURITY EVIDENCED HEREBY MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED IN
THE ABSENCE OF SUCH REGISTRATION OR AN APPLICABLE EXEMPTION THEREFROM. EACH
PURCHASER OF THE SECURITY EVIDENCED HEREBY IS HEREBY NOTIFIED THAT THE SELLER
MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE
SECURITIES ACT PROVIDED BY RULE 144A THEREUNDER. THE HOLDER OF THE SECURITY
EVIDENCED HEREBY AGREES FOR THE BENEFIT OF THE ISSUER THAT (A) SUCH SECURITY MAY
BE RESOLD, PLEDGED OR OTHERWISE TRANSFERRED ONLY (1) (a) IN THE UNITED STATES TO
A PERSON WHO THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER
(AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT) IN A TRANSACTION MEETING THE
REQUIREMENTS OF RULE 144A, (b) OUTSIDE THE UNITED STATES IN AN OFFSHORE
TRANSACTION IN ACCORDANCE WITH RULE 904 UNDER THE SECURITIES ACT, (c) IN A
TRANSACTION MEETING THE REQUIREMENTS OF RULE 144 UNDER THE SECURITIES ACT, (d)
TO AN INSTITUTIONAL "ACCREDITED INVESTOR" (AS DEFINED IN RULE 501 (a) (1), (2),
(3) OR (7) OF THE SECURITIES ACT (AN "INSTITUTIONAL ACCREDITED INVESTOR")) THAT,
PRIOR TO SUCH TRANSFER, FURNISHES THE TRUSTEE A SIGNED LETTER CONTAINING CERTAIN
REPRESENTATIONS AND AGREEMENTS (THE FORM OF WHICH CAN BE OBTAINED FROM THE
TRUSTEE) AND, IF SUCH TRANSFER IS IN RESPECT OF AN AGGREGATE PRINCIPAL AMOUNT OF
NOTES LESS THAN $250,000, AN OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY THAT
SUCH TRANSFER IS IN COMPLIANCE WITH THE SECURITIES ACT OR (e) IN ACCORDANCE WITH
ANOTHER EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT (AND
BASED UPON AN OPINION OF COUNSEL IF THE COMPANY SO REQUESTS), (2) TO THE COMPANY
OR (3) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT AND, IN EACH CASE, IN
ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES
OR ANY OTHER APPLICABLE JURISDICTION AND (B) THE HOLDER WILL, AND EACH
SUBSEQUENT HOLDER IS REQUIRED TO, NOTIFY ANY PURCHASER FROM IT OF THE

----------
/1/     This paragraph should be included only if the Note is issued in global
        form

                                      A-1-2

<PAGE>

SECURITY EVIDENCED HEREBY OF THE RESALE RESTRICTIONS SET FORTH IN (A)
ABOVE."]/2/

        1.      Interest. Frontier Escrow Corporation, a Delaware corporation,
together with its successors in accordance with the terms of the Indenture (the
"Company"), promises to pay interest on the principal amount of this Note at
8.000% per annum from _______________, until maturity [and shall pay the
Liquidated Damages payable pursuant to the Registration Rights Agreement
referred to below]/3/. The Company will pay interest and Liquidated Damages, if
any, semi-annually in arrears on April 15 and October 15 of each year,
commencing _______________, or if any such day is not a Business Day, on the
next succeeding Business Day (each an "Interest Payment Date"). Interest on the
Notes will accrue from the most recent date to which interest has been paid or,
if no interest has been paid, from the date of original issuance; provided that
if there is no existing Default or Event of Default in the payment of interest,
and if this Note is authenticated between a record date referred to on the face
hereof and the next succeeding Interest Payment Date, interest shall accrue from
such next succeeding Interest Payment Date, except in the case of the original
issuance of Notes, in which case interest shall accrue from the date of
authentication. The Company shall, to the extent lawful, pay interest (including
post-petition interest in any proceeding under any Bankruptcy Law) on overdue
principal and premium, if any, from time to time on demand at a rate that is the
rate then in effect; it shall, to the extent lawful, pay interest (including
post-petition interest in any proceeding under any Bankruptcy Law) on overdue
installments of interest and any Liquidated Damages (without regard to any
applicable grace periods) from time to time on demand at the same rate. Interest
will be computed on the basis of a 360-day year of twelve 30-day months.

        2.      Method of Payment. The Company will pay interest on the Notes
(except defaulted interest) and Liquidated Damages, if any, to the Persons who
are registered Holders of Notes at the close of business on the April 1 or
October 1 next preceding the Interest Payment Date, even if such Notes are
canceled after such record date and on or before such Interest Payment Date,
except as provided in Section 2.12 of the Indenture with respect to defaulted
interest. The Notes will be payable as to principal, premium, interest and
Liquidated Damages, if any, at the office or agency of the Company maintained
for such purpose within the Borough of Manhattan, the City and State of New
York, or, at the option of the Company, payment of interest and Liquidated
Damages, if any, may be made from such office or agency by check mailed to the
Holders at their addresses set forth in the register of Holders, and provided
that payment by wire transfer of immediately available funds will be required
with respect to principal of and interest, premium and Liquidated Damages, if
any, on all Global Notes and all other Notes the Holders of which shall have
provided wire transfer instructions to the Company or the Paying Agent. Such
payment shall be in such coin or currency of the United States of America as at
the time of payment is legal tender for payment of public and private debts.

        3.      Paying Agent and Registrar. Initially, Wells Fargo Bank, N.A.,
the Trustee under the Indenture, acting through its office in the Borough of
Manhattan, the City and State of New York, will act as Paying Agent and
Registrar. The Company may change any Paying Agent or Registrar without notice
to any Holder. None of the Company, any of its Subsidiaries or Parent may act in
any such capacity.

----------
/2/     This bracketed provision applies only to Series A Notes that are
        Transfer Restricted Securities, and it should be removed upon the
        exchange of such Series A Notes for Series B Notes in an Exchange Offer
        or upon the transfer of such Series A Notes that have been sold pursuant
        to the terms of the Shelf Registration contemplated by the applicable
        Registration Rights Agreement.

/3/     This bracketed provision applies only to Series A Notes that are
        Transfer Restricted Securities, and it should be removed upon the
        exchange of such Series A Notes for Series B Notes in an Exchange Offer
        or upon the transfer of such Series A Notes that have been sold pursuant
        to the terms of the Shelf Registration contemplated by the applicable
        Registration Rights Agreement.

                                      A-1-3

<PAGE>

        4.      Indenture. The Company issued the Notes under an Indenture dated
as of April 17, 2003 ("Indenture") between the Company and the Trustee. The
terms of the Notes include those stated in the Indenture and those made part of
the Indenture by reference to the Trust Indenture Act of 1939, as amended (15
U.S. Code Sections 77aaa-77bbbb). The Notes are subject to all such terms, and
Holders are referred to the Indenture and such Act for a statement of such
terms. The Notes are general unsecured obligations of the Company limited in
aggregate principal amount to $220,000,000 issued on the Issue Date (the
"Offered Notes") and an unlimited aggregate additional principal amount issuable
thereafter under the terms of the Indenture.

        5.      Optional Redemption.

        (a)     Except as set forth in subparagraph (b) of this Paragraph 5, the
Company shall not have the option to redeem the Notes prior to April 15, 2008.
Thereafter, the Company shall have the option to redeem the Notes, in whole or
in part, upon not less than 30 nor more than 60 days' notice, at the redemption
prices (expressed as percentages of principal amount) set forth below plus
accrued and unpaid interest and Liquidated Damages, if any, thereon to the
applicable redemption date, if redeemed during the twelve-month period beginning
on April 15 of the years indicated below:

                YEAR                            PERCENTAGE
                ----                            ----------
                2008                            104.000%
                2009                            102.667%
                2010                            101.333%
                2011 and thereafter             100.000%

        (b)     Notwithstanding the provisions of subparagraph (a) of this
Paragraph 5, (x) following the consummation of the Escrow Corp. Merger, the
Company may at any time prior to April 15, 2008, at its option, redeem the
Notes, in whole or in part, at the Make-Whole Price, plus accrued and unpaid
interest and Liquidated Damages, if any, thereon to the redemption date and (y)
at any time prior to April 15, 2006 and after the consummation of the Escrow
Corp. Merger, the Company may redeem up to 35% of the aggregate principal amount
of Notes issued under the Indenture at a redemption price of 108.000% of the
principal amount thereof, plus accrued and unpaid interest and Liquidated
Damages, if any, thereon to the redemption date, with the net cash proceeds of
one or more Equity Offerings (provided that, if the Equity Offering is an
offering by Parent, a portion of the Net Cash Proceeds thereof equal to the
amount required to redeem any such Notes is contributed to the equity capital of
the Company or used to acquire Capital Stock of the Company (other than
Disqualified Stock) from the Company); provided that (a) at least 65% of the
aggregate principal amount of Notes issued under the Indenture remains
outstanding immediately after the occurrence of each such redemption pursuant to
this clause (y) (excluding Notes held by the Company or its Affiliates) and (b)
each such redemption shall occur within 120 days of the date of the closing of
each such Equity Offering.

        6.      Mandatory Redemption.

        (a)     Except as described in subparagraph (b) of this Paragraph 6 or
in Paragraph 7 below, the Company shall not be required to make mandatory
redemption or sinking fund payments with respect to the Notes.

        (b)     Subject to the terms and conditions of Section 3.08(b) of the
Indenture, the Company shall be required to redeem all of the Offered Notes on
the Special Mandatory Redemption Date at the redemption price specified in such
Section 3.08(b), plus accrued and unpaid interest on the Offered Notes to the
Special Mandatory Redemption Date, if the Merger has not closed on or prior to
the Special Mandatory Redemption Date.

                                      A-1-4

<PAGE>

        7.      Repurchase at Option of Holder.

        (a)     If there is a Change of Control, the Company shall be required
to make an offer (a "Change of Control Offer") to repurchase all or any part
(equal to $1,000 or an integral multiple thereof unless all of the Notes held by
a Holder are to be purchased) of each Holder's Notes at a purchase price equal
to 101% of the aggregate principal amount thereof, plus accrued and unpaid
interest and Liquidated Damages, if any, thereon to the date of purchase (the
"Change of Control Payment"). Within 30 days following any Change of Control,
the Company shall mail a notice to each Holder describing the transaction that
constitutes the Change of Control and setting forth the procedures governing the
Change of Control Offer as required by the Indenture.

        (b)     If the Company or a Restricted Subsidiary consummates any Asset
Sales, within 30 days of each date on which the aggregate amount of Excess
Proceeds exceeds $20.0 million, the Company shall commence an offer to all
Holders of Notes (an "Asset Sale Offer") pursuant to Section 3.09 of the
Indenture to purchase the maximum principal amount of Notes (equal to an
integral multiple of $1,000) that may be purchased out of the Excess Proceeds at
an offer price in cash in an amount equal to 100% of the principal amount
thereof plus accrued and unpaid interest and Liquidated Damages, if any, thereon
to the date of purchase, in accordance with the procedures set forth in the
Indenture; provided, however, that, if the Company is required to apply such
Excess Proceeds to repurchase, or to offer to repurchase, any Pari Passu
Indebtedness, the Company shall only be required to offer to repurchase the
maximum principal amount of Notes that may be purchased out of the amount of
such Excess Proceeds multiplied by a fraction, the numerator of which is the
aggregate principal amount of Notes outstanding and the denominator of which is
the aggregate principal amount of Notes outstanding plus the aggregate principal
amount of Pari Passu Indebtedness outstanding. To the extent that the aggregate
amount of Notes tendered pursuant to an Asset Sale Offer is less than such
Excess Proceeds, the Company may use any remaining Excess Proceeds for purposes
not otherwise prohibited by the Indenture. If the aggregate principal amount of
Notes surrendered by Holders thereof exceeds such amount of Excess Proceeds, the
Trustee shall select the Notes to be purchased on a pro rata basis (with such
adjustments as may be deemed appropriate by the Trustee so that only Notes in
denominations of $1,000, or integral multiples thereof, shall be purchased with
such available amount of Excess Proceeds). Holders of Notes that are the subject
of an offer to purchase will receive an Asset Sale Offer from the Company prior
to any related purchase date and may elect to have such Notes purchased by
completing the form entitled "Option of Holder to Elect Purchase" on the reverse
of the Notes.

        8.      Notice of Redemption. Notice of redemption will be mailed at
least 30 days (or such shorter period as may be acceptable to DTC in the case of
a mandatory redemption) but not more than 60 days before the redemption date to
each Holder whose Notes are to be redeemed at its registered address. Notes in
denominations larger than $1,000 may be redeemed in part but only in whole
multiples of $1,000, unless all of the Notes held by a Holder are to be
redeemed. On and after the redemption date interest ceases to accrue on Notes or
portions thereof called for redemption.

        9.      Denominations, Transfer, Exchange. The Notes are in registered
form without coupons in denominations of $1,000 and integral multiples of
$1,000. The transfer of Notes may be registered and Notes may be exchanged as
provided in the Indenture. The Registrar and the Trustee may require a Holder,
among other things, to furnish appropriate endorsements and transfer documents
and the Company may require a Holder to pay any taxes and fees required by law
or permitted by the Indenture. The Company need not exchange or register the
transfer of any Note or portion of a Note selected for redemption, except for
the unredeemed portion of any Note being redeemed in part. Also, it need not
exchange or register the transfer of any Notes for a period of 15 days before a
selection of Notes to be redeemed or during the period between a record date and
the corresponding Interest Payment Date.

                                      A-1-5

<PAGE>

        10.     Persons Deemed Owners. The registered Holder of a Note may be
treated as its owner for all purposes.

        11.     Amendment, Supplement and Waiver. Subject to certain exceptions,
the Indenture, the Notes and the Guarantees may be amended or supplemented with
the consent of the Holders of at least a majority in principal amount of the
then outstanding Notes, and any existing default or compliance with any
provision of the Indenture, the Notes or the Guarantees may be waived with the
consent of the Holders of a majority in principal amount of the then outstanding
Notes. Without the consent of any Holder of a Note, the Indenture, the Notes or
the Guarantees may be amended or supplemented to cure any ambiguity, defect or
inconsistency, to provide for uncertificated Notes in addition to or in place of
certificated Notes or to alter the provisions of Article 2 of the Indenture
(including the related definitions) in a manner that does not materially
adversely affect any Holder, to provide for the assumption of the Company's or a
Guarantor's obligations to Holders of the Notes in case of a merger or
consolidation, to make any change that would provide any additional rights or
benefits to the Holders of the Notes or that does not adversely affect the legal
rights under the Indenture of any such Holder, to comply with Article 10 of the
Indenture, to secure the Notes pursuant to the requirements of Section 4.12 or
otherwise, to add any Guarantor or to release any Guarantor from its Guarantee,
in each case as provided in the Indenture, to conform the text of the Indenture,
the Guarantees or the Notes to any provision found under the heading
"Description of the Notes" in the Company's Offering Memorandum relating to the
Notes to the extent that such provision was intended to be a verbatim recitation
of a provision of the Indenture, the Guarantees or the Notes, as applicable, or
to comply with the requirements of the Commission in order to effect or maintain
the qualification of the Indenture under the Trust Indenture Act.

        12.     Defaults and Remedies. Events of Default include: (i) default
for 30 days in the payment when due of interest or Liquidated Damages on the
Notes; (ii) default in payment when due of the principal of or premium, if any,
on the Notes; (iii) failure by the Company or any of its Subsidiaries or Parent
to comply with Section 4.15 or 5.01 of the Indenture; (iv) failure by Frontier
Escrow Corporation to comply with the provisions of Section 4.19; (v) failure by
the Company for 60 days after notice to comply with any of its other agreements
in the Indenture, the Notes or the Escrow Agreement; (vi) default under any
mortgage, indenture or instrument under which there may be issued or by which
there may be secured or evidenced any Indebtedness for money borrowed by the
Company, any of its Restricted Subsidiaries or Parent (or the payment of which
is guaranteed by the Company or any of its Restricted Subsidiaries or Parent),
whether such Indebtedness or guarantee now exists, or is created after the Issue
Date, which default (a) is caused by a failure to pay principal of or premium or
interest on such Indebtedness prior to the expiration of any grace period
provided in such Indebtedness (a "Payment Default") or (b) results in the
acceleration of such Indebtedness prior to its express maturity and, in each
case, the principal amount of any such Indebtedness, together with the principal
amount of any other such Indebtedness under which there has been a Payment
Default or the maturity of which has been so accelerated, aggregates $10.0
million or more; and provided, further, that if such default is cured or waived
or any such acceleration rescinded, or such Indebtedness is repaid within a
period of 10 days from the continuation of such default beyond the applicable
grace period or the occurrence of such acceleration, as the case may be, an
Event of Default and any consequential acceleration of the Notes shall be
automatically rescinded, so long as said rescission does not conflict with any
judgment or decree; (vii) failure by the Company, any of its Restricted
Subsidiaries or Parent to pay final judgments aggregating in excess of $10.0
million (net of applicable insurance coverage which is acknowledged in writing
by the insurer), which judgments are not paid, discharged or stayed for a period
of 60 days; (viii) failure by Parent to execute a supplemental indenture and a
Guarantee upon consummation of the Mergers; (ix) failure by any Guarantor to
perform any covenant set forth in its Guarantee, or the repudiation by any
Guarantor of its obligations under its Guarantee or the unenforceability of any
Guarantee against a Guarantor for any reason; (x) failure of the Escrow
Agreement, at any time, to be in full force and effect (except as provided in
the Indenture) or any contest by the Company or any of its

                                      A-1-6

<PAGE>

Subsidiaries or Parent of the validity or enforceability of the Escrow
Agreement; and (xi) certain events of bankruptcy or insolvency with respect to
the Company, Parent, any Restricted Subsidiary that is also a Significant
Subsidiary or any group of Subsidiaries that, taken as a whole, would constitute
a Significant Subsidiary, pursuant to or within the meaning of Bankruptcy Law as
provided in the Indenture. If any Event of Default occurs and is continuing, the
Trustee or the Holders of at least 25% in principal amount of the then
outstanding Notes may declare all the Notes to be due and payable immediately.
Notwithstanding the foregoing, in the case of an Event of Default arising from
certain events of bankruptcy or insolvency, all outstanding Notes will become
due and payable without further action or notice. Holders may not enforce the
Indenture or the Notes except as provided in the Indenture. Subject to certain
limitations, Holders of a majority in principal amount of the then outstanding
Notes may direct the Trustee in its exercise of any trust or power. The Trustee
may withhold from Holders of the Notes notice of any continuing Default or Event
of Default (except a Default or Event of Default relating to the payment of
principal, interest, premium or Liquidated Damages, if any), if it determines
that withholding notice is in their interest. The Holders of a majority in
aggregate principal amount of the Notes then outstanding by notice to the
Trustee may on behalf of the Holders of all of the Notes waive any existing
Default or Event of Default and its consequences under the Indenture, except a
continuing Default or Event of Default in the payment of the principal of or
premium, interest or Liquidated Damages, if any, on the Notes. The Company is
required to deliver to the Trustee annually a statement regarding compliance
with the Indenture, and the Company is required upon becoming aware of any
Default or Event of Default, to deliver to the Trustee a statement specifying
such Default or Event of Default.

        13.     Defeasance. The Notes are subject to defeasance upon the terms
and conditions specified in the Indenture.

        14.     Trustee Dealings with Company. The Trustee, in its individual or
any other capacity, may make loans to, accept deposits from, and perform
services for the Company, any Guarantor or any Affiliate of the Company, and may
otherwise deal with the Company, any Guarantor or any Affiliates of the Company,
as if it were not the Trustee.

        15.     No Recourse Against Others. A director, officer, employee,
incorporator or stockholder, of the Company or any Guarantor, as such, shall not
have any liability for any obligations of the Company or any Guarantor under the
Notes, the Guarantees or the Indenture or for any claim based on, in respect of,
or by reason of, such obligations or their creation. Each Holder by accepting a
Note waives and releases all such liability. The waiver and release are part of
the consideration for the issuance of the Notes.

        16.     Authentication. This Note shall not be valid until authenticated
by the manual signature of an authorized signatory of the Trustee or an
authenticating agent.

        17.     Abbreviations. Customary abbreviations may be used in the name
of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN ENT (=
tenants by the entireties), JT TEN (= joint tenants with right of survivorship
and not as tenants in common), CUST (= Custodian), and U/G/M/A (= Uniform Gifts
to Minors Act).

        18.     [Additional Rights of Holders of Transfer Restricted Securities.
In addition to the rights provided to Holders of Notes under the Indenture,
Holders of Transfer Restricted Securities shall have all

                                      A-1-7

<PAGE>

the rights set forth in the Registration Rights Agreement dated as of
____________, between the Company, Parent and each Initial Purchaser named
therein (the "Registration Rights Agreement").]/4/

        19.     CUSIP Numbers. Pursuant to a recommendation promulgated by the
Committee on Uniform Security Identification Procedures, the Company has caused
CUSIP numbers to be printed on the Notes and the Trustee may use CUSIP numbers
in notices of redemption as a convenience to Holders. No representation is made
as to the accuracy of such numbers either as printed on the Notes or as
contained in any notice of redemption and reliance may be placed only on the
other identification numbers placed thereon.

        The Company will furnish to any Holder upon written request and without
charge a copy of the Indenture and/or the Registration Rights Agreement.
Requests may be made to:

                        Frontier Escrow Corporation
                        10000 Memorial Drive, Suite 600
                        Houston, Texas   77024-3411
                        Attention:  Secretary

----------
/4/     This bracketed provision applies only to Series A Notes that are
        Transfer Restricted Securities, and it should be removed upon the
        exchange of such Series A Notes for Series B Notes in an Exchange Offer
        or upon the transfer of such Series A Notes that have been sold pursuant
        to the terms of the Shelf Registration contemplated by the applicable
        Registration Rights Agreement.

                                      A-1-8

<PAGE>

                                 ASSIGNMENT FORM

        To assign this Note, fill in the form below: (I) or (we) assign and
transfer this Note to

                  (Insert assignee's soc. sec. or tax I.D. no.)
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
              (Print or type assignee's name, address and zip code)

and irrevocably appoint ___________________________________________________ to
transfer this Note on the books of the Company. The agent may substitute another
to act for him.

________________________________________________________________________________

Date: __________________
                                         Your Signature:
                                                        ------------------------
                                         (Sign exactly as your name appears
                                         on the face of this Note)

                                         Signature Guarantee:

                                      A-1-9

<PAGE>

                       OPTION OF HOLDER TO ELECT PURCHASE

        If you want to elect to have this Note purchased by the Company pursuant
to Section 4.10 or 4.15 of the Indenture, check the box below:

                [_] Section 4.10                [_] Section 4.15

        If you want to elect to have only part of the Note purchased by the
Company pursuant to Section 4.10 or Section 4.15 of the Indenture, state the
amount you elect to have purchased: $___________

Date: ______________                     Your Signature:
                                                        ------------------------
                                         (Sign exactly as your name appears on
                                          the Note)
                                         Social Security or
                                         Tax Identification No.:
                                                                ----------------

                                         Signature Guarantee:

                                     A-1-10

<PAGE>

                         SCHEDULE OF EXCHANGES OF NOTES/5/

THE FOLLOWING EXCHANGES OF A PART OF THIS GLOBAL NOTE FOR OTHER NOTES HAVE BEEN
MADE:

<TABLE>
<CAPTION>
                                                                          Principal Amount of
                                                                           this Global Note         Signature of
                           Amount of decrease    Amount of increase in      following such       authorized officer
                           in Principal Amount    Principal Amount of        decrease (or        of Trustee or Note
    Date of Exchange       of this Global Note      this Global Note           increase)              Custodian
---------------------      -------------------   ---------------------    --------------------   ------------------
<S>                        <C>                   <C>                      <C>                      <C>
</TABLE>

----------
/5/     This should be included only if the Note is issued in global form.

                                     A-1-11

<PAGE>

                                                                     EXHIBIT A-2

                  (Face of Regulation S Temporary Global Note)
               8.000% SENIOR NOTES DUE 2013, [SERIES A] [SERIES B]

No. _______________
       CUSIP NO.

                           FRONTIER ESCROW CORPORATION

promises to pay to Cede & Co. or registered assigns, the principal sum of ______
Dollars on April 15, 2013.

                 Interest Payment Dates: April 15 and October 15
                       Record Dates: April 1 and October 1

                                                FRONTIER ESCROW CORPORATION

                                                By:
                                                    ----------------------------
                                                    Name:
                                                    Title:

Trustee's Certificate of Authentication:

This is one of the Notes referred to in the within-mentioned Indenture.

WELLS FARGO BANK , N.A., as Trustee

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

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

                                      A-2-1

<PAGE>

                  (Back of Regulation S Temporary Global Note)

               8.000% SENIOR NOTES DUE 2013, [SERIES A] [SERIES B]

        "THIS GLOBAL NOTE IS HELD BY THE DEPOSITARY (AS DEFINED IN THE INDENTURE
GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE BENEFICIAL
OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY CIRCUMSTANCES
EXCEPT THAT (I) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS MAY BE REQUIRED
PURSUANT TO SECTION 2.06 OF THE INDENTURE, (II) THIS GLOBAL NOTE MAY BE
EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 2.06 OF THE INDENTURE,
(III) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE FOR CANCELLATION PURSUANT
TO SECTION 2.11 OF THE INDENTURE AND (IV) THIS GLOBAL NOTE MAY BE TRANSFERRED TO
A SUCCESSOR DEPOSITARY WITH THE PRIOR WRITTEN CONSENT OF THE COMPANY."

        "THE SECURITY (OR ITS PREDECESSOR) EVIDENCED HEREBY WAS ORIGINALLY
ISSUED IN A TRANSACTION EXEMPT FROM REGISTRATION UNDER SECTION 5 OF THE UNITED
STATES SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), AND THE
SECURITY EVIDENCED HEREBY MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED IN
THE ABSENCE OF SUCH REGISTRATION OR AN APPLICABLE EXEMPTION THEREFROM. EACH
PURCHASER OF THE SECURITY EVIDENCED HEREBY IS HEREBY NOTIFIED THAT THE SELLER
MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE
SECURITIES ACT PROVIDED BY RULE 144A THEREUNDER. THE HOLDER OF THE SECURITY
EVIDENCED HEREBY AGREES FOR THE BENEFIT OF THE ISSUER THAT (A) SUCH SECURITY MAY
BE RESOLD, PLEDGED OR OTHERWISE TRANSFERRED ONLY (1) (a) IN THE UNITED STATES TO
A PERSON WHO THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER
(AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT) IN A TRANSACTION MEETING THE
REQUIREMENTS OF RULE 144A, (b) OUTSIDE THE UNITED STATES IN AN OFFSHORE
TRANSACTION IN ACCORDANCE WITH RULE 904 UNDER THE SECURITIES ACT, (c) IN A
TRANSACTION MEETING THE REQUIREMENTS OF RULE 144 UNDER THE SECURITIES ACT, (d)
TO AN INSTITUTIONAL "ACCREDITED INVESTOR" (AS DEFINED IN RULE 501 (a) (1), (2),
(3) OR (7) OF THE SECURITIES ACT (AN "INSTITUTIONAL ACCREDITED INVESTOR")) THAT,
PRIOR TO SUCH TRANSFER, FURNISHES THE TRUSTEE A SIGNED LETTER CONTAINING CERTAIN
REPRESENTATIONS AND AGREEMENTS (THE FORM OF WHICH CAN BE OBTAINED FROM THE
TRUSTEE) AND, IF SUCH TRANSFER IS IN RESPECT OF AN AGGREGATE PRINCIPAL AMOUNT OF
NOTES LESS THAN $250,000, AN OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY THAT
SUCH TRANSFER IS IN COMPLIANCE WITH THE SECURITIES ACT OR (e) IN ACCORDANCE WITH
ANOTHER EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT (AND
BASED UPON AN OPINION OF COUNSEL IF THE COMPANY SO REQUESTS), (2) TO THE COMPANY
OR (3) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT AND, IN EACH CASE, IN
ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES
OR ANY OTHER APPLICABLE JURISDICTION AND (B) THE HOLDER WILL, AND EACH
SUBSEQUENT HOLDER IS REQUIRED TO, NOTIFY ANY PURCHASER FROM IT OF THE SECURITY
EVIDENCED HEREBY OF THE RESALE RESTRICTIONS SET FORTH IN (A) ABOVE."

                                      A-2-2

<PAGE>

        THE RIGHTS ATTACHING TO THIS REGULATION S TEMPORARY GLOBAL NOTE, AND THE
CONDITIONS AND PROCEDURES GOVERNING ITS EXCHANGE FOR CERTIFICATED NOTES, ARE AS
SPECIFIED IN THE INDENTURE (AS DEFINED HEREIN).

        NEITHER THE HOLDER NOR THE BENEFICIAL OWNERS OF THIS REGULATION S
TEMPORARY GLOBAL NOTE SHALL BE ENTITLED TO RECEIVE PAYMENT OF INTEREST HEREON OR
LIQUIDATED DAMAGES PRIOR TO THE EXCHANGE OF THIS NOTE FOR A REGULATION S
PERMANENT GLOBAL NOTE AS CONTEMPLATED BY THE INDENTURE.

        Frontier Escrow Corporation, a Delaware corporation, together with its
successors in accordance with the terms of the Indenture (the "Company"),
promises to pay interest on the principal amount of this Note at the rate of
8.000% per annum from ____________, until maturity and shall pay the Liquidated
Damages payable pursuant to the Registration Rights Agreement referred to in the
Indenture. The Company will pay interest and Liquidated Damages, if any, in
United States dollars semi-annually in arrears on April 15 and October 15,
commencing on __________, or if any such day is not a Business Day, on the next
succeeding Business Day (each an "Interest Payment Date"). Interest on the Notes
shall accrue from the most recent date to which interest has been paid or, if no
interest has been paid, from the date of original issuance; provided that if
there is no existing Default or Event of Default in the payment of interest, and
if this Note is authenticated between a record date referred to on the face
hereof and the next succeeding Interest Payment Date, interest shall accrue from
such next succeeding Interest Payment Date, except in the case of the original
issuance of Notes, in which case interest shall accrue from the date of
authentication. The Company shall pay interest (including post-petition interest
in any proceeding under any Bankruptcy Law) on overdue principal and premium, if
any from time to time on demand at a rate equal to the then applicable interest
rate on the Notes; it shall pay interest (including post- petition interest in
any proceeding under any Bankruptcy Law) on overdue installments of interest and
Liquidated Damages (without regard to any applicable grace period) from time to
time on demand at the same rate to the extent lawful. Interest shall be computed
on the basis of a 360-day year comprised of twelve 30-day months.

        This Regulation S Temporary Global Note is issued in respect of an issue
of 8.000% Senior Notes due 2013 (the "Notes") of the Company, limited in
aggregate principal amount to $220,000,000 issued on the Issue Date (the
"Offered Notes") and an unlimited aggregate additional principal amount issuable
thereafter under the terms of the Indenture, plus amounts, if any, sufficient to
pay premium, if any, interest or Liquidated Damages, if any on outstanding
Notes. The Company has issued the Notes under an Indenture (the "Indenture")
dated as of April 17, 2003, between the Company and the Trustee. This Regulation
S Temporary Global Note is governed by the terms and conditions of the Indenture
governing the Notes, which terms and conditions are incorporated herein by
reference and, except as otherwise provided herein, shall be binding on the
Company and the Holder hereof as if fully set forth herein. Unless the context
otherwise requires, the terms used herein shall have the meanings specified in
the Indenture.

        Until this Regulation S Temporary Global Note is exchanged for
Regulation S Permanent Global Notes, the Holder hereof shall not be entitled to
receive payments of interest or Liquidated Damages, if any, hereon although
interest and Liquidated Damages, if any, will continue to accrue. Until so
exchanged in full, this Regulation S Temporary Global Note shall in all other
respects be entitled to the same benefits as other Notes under the Indenture.

        This Regulation S Temporary Global Note is exchangeable in whole or in
part for one or more Regulation S Permanent Global Notes only (i) on or after
the termination of the 40-day restricted period (as defined in Regulation S) and
(ii) upon presentation of certificates required by Article 2 of the

                                      A-2-3

<PAGE>

Indenture. Upon exchange of this Regulation S Temporary Global Note for one or
more Regulation S Permanent Global Notes, the Trustee shall cancel this
Regulation S Temporary Global Note.

        This Regulation S Temporary Global Note shall not become valid or
obligatory until the certificate of authentication hereon shall have been duly
manually signed by an authorized signatory of the Trustee in accordance with the
Indenture. This Regulation S Temporary Global Note shall be governed by and
construed in accordance with the laws of the State of the New York. All
references to "$," "Dollars," "dollars" or "U.S. $" are to such coin or currency
of the United States of America as at the time shall be legal tender for the
payment of public and private debts therein.

                                      A-2-4

<PAGE>

                     SCHEDULE OF EXCHANGES FOR GLOBAL NOTES

        The following exchanges of a part of this Regulation S Temporary Global
Note for other Global Notes have been made:

<TABLE>
<CAPTION>
                                                                          Principal Amount of
                                                                           this Global Note         Signature of
                           Amount of decrease    Amount of increase in      following such       authorized officer
                           in Principal Amount    Principal Amount of        decrease (or        of Trustee or Note
    Date of Exchange       of this Global Note      this Global Note           increase)              Custodian
-----------------------   --------------------   ----------------------   ---------------------  ------------------
<S>                        <C>                   <C>                      <C>                    <C>
</TABLE>

                                      A-2-5

<PAGE>

                                                                       EXHIBIT B

                         FORM OF CERTIFICATE OF TRANSFER

Frontier Escrow Corporation
10000 Memorial Drive, Suite 600
Houston, Texas  77024-3411

[Registrar address block]

        Re: 8.000% Senior Notes due 2013

        Reference is hereby made to the Indenture, dated as of April 17, 2003
(the "Indenture"), between Frontier Escrow Corporation, as issuer (the
"Company"), and Wells Fargo Bank, N.A., as trustee. Capitalized terms used but
not defined herein shall have the meanings given to them in the Indenture.

        ___________________, (the "Transferor") owns and proposes to transfer
the Note[s] or interest in such Note[s] specified in Annex A hereto, in the
principal amount of $___________ in such Note[s] or interests (the "Transfer"),
to ___________________________ (the "Transferee"), as further specified in Annex
A hereto. In connection with the Transfer, the Transferor hereby certifies that:

                             [CHECK ALL THAT APPLY]

        1. [ ]  Check if Transferee will take delivery of a beneficial interest
in the 144A Global Note or a Definitive Note Pursuant to Rule 144A. The Transfer
is being effected pursuant to and in accordance with Rule 144A under the United
States Securities Act of 1933, as amended (the "Securities Act"), and,
accordingly, the Transferor hereby further certifies that the beneficial
interest or Definitive Note is being transferred to a Person that the Transferor
reasonably believed and believes is purchasing the beneficial interest or
Definitive Note for its own account, or for one or more accounts with respect to
which such Person exercises sole investment discretion, and such Person and each
such account is a "qualified institutional buyer" within the meaning of Rule
144A in a transaction meeting the requirements of Rule 144A and such Transfer is
in compliance with any applicable blue sky securities laws of any state of the
United States. Upon consummation of the proposed Transfer in accordance with the
terms of the Indenture, the transferred beneficial interest or Definitive Note
will be subject to the restrictions on transfer enumerated in the Private
Placement Legend printed on the 144A Global Note and/or the Definitive Note and
in the Indenture and the Securities Act.

        2. [ ]  Check if Transferee will take delivery of a beneficial interest
in the Temporary Regulation S Global Note, the Regulation S Global Note or a
Definitive Note pursuant to Regulation S. The Transfer is being effected
pursuant to and in accordance with Rule 903 or Rule 904 or Rule 144 (if
applicable) under the Securities Act and, accordingly, the Transferor hereby
further certifies that (i) the Transfer is not being made to a person in the
United States and (x) at the time the buy order was originated, the Transferee
was outside the United States or such Transferor and any Person acting on its
behalf reasonably believed and believes that the Transferee was outside the
United States or (y) the transaction was executed in, on or through the
facilities of a designated offshore securities market and neither such
Transferor nor any Person acting on its behalf knows that the transaction was
prearranged with a buyer in the United States, (ii) no directed selling efforts
have been made in contravention of the requirements of Rule 903(b) or Rule
904(b) of Regulation S under the Securities Act, (iii) the transaction is not
part of a plan or scheme to evade the registration requirements of the
Securities Act and (iv) if the proposed transfer is being made prior to the
expiration of the Restricted Period, the interest transferred will be held
immediately thereafter through Euroclear or Clearstream. Upon consummation of
the

                                       B-1

<PAGE>

proposed transfer in accordance with the terms of the Indenture, the transferred
beneficial interest or Definitive Note will be subject to the restrictions on
Transfer enumerated in the Private Placement Legend printed on the Regulation S
Global Note, the Temporary Regulation S Global Note and/or the Definitive Note
and in the Indenture and the Securities Act.

        3. [ ]  Check and complete if Transferee will take delivery of a
beneficial interest in the 144A Global Note or a Definitive Note pursuant to any
provision of the Securities Act other than Rule 144A or Regulation S. The
Transfer is being effected in compliance with the transfer restrictions
applicable to beneficial interests in Restricted Global Notes and Restricted
Definitive Notes and pursuant to and in accordance with the Securities Act and
any applicable blue sky securities laws of any state of the United States, and
accordingly the Transferor hereby further certifies that (check one):

                (a) [ ] such Transfer is being effected pursuant to and in
        accordance with Rule 144 under the Securities Act;

                                       or

                (b) [ ] such Transfer is being effected to the Company or a
        subsidiary thereof;

                                       or

                (c) [ ] such Transfer is being effected pursuant to an effective
        registration statement under the Securities Act and in compliance with
        the prospectus delivery requirements of the Securities Act;

                                       or

                (d) [ ] such Transfer is being effected to an Institutional
        Accredited Investor and pursuant to an exemption from the registration
        requirements of the Securities Act other than Rule 144A, Rule 144 or
        Rule 904, and the Transferor hereby further certifies that it has not
        engaged in any general solicitation within the meaning of Regulation D
        under the Securities Act and the Transfer complies with the transfer
        restrictions applicable to beneficial interests in a Restricted Global
        Note or Restricted Definitive Notes and the requirements of the
        exemption claimed, which certification is supported by (1) a certificate
        executed by the Transferee in the form of Exhibit D to the Indenture and
        (2) if such Transfer is in respect of a principal amount of Notes at the
        time of transfer of less than $250,000, an Opinion of Counsel provided
        by the Transferor or the Transferee (a copy of which the Transferor has
        attached to this certification), to the effect that such Transfer is in
        compliance with the Securities Act. Upon consummation of the proposed
        transfer in accordance with the terms of the Indenture, the transferred
        beneficial interest or Definitive Note will be subject to the
        restrictions on transfer enumerated in the Private Placement Legend
        printed on the 144A Global Note and/or the Definitive Notes and in the
        Indenture and the Securities Act.

        4. [ ]  Check if Transferee will take delivery of a beneficial interest
in an Unrestricted Global Note or of an Unrestricted Definitive Note.

        (a) [ ] Check if Transfer is pursuant to Rule 144. (i) The Transfer is
being effected pursuant to and in accordance with Rule 144 under the Securities
Act and in compliance with the transfer restrictions contained in the Indenture
and any applicable blue sky securities laws of any state of the United States
and (ii) the restrictions on transfer contained in the Indenture and the Private
Placement Legend are not required in order to maintain compliance with the
Securities Act. Upon consummation of

                                       B-2

<PAGE>

the proposed Transfer in accordance with the terms of the Indenture, the
transferred beneficial interest or Definitive Note will no longer be subject to
the restrictions on transfer enumerated in the Private Placement Legend printed
on the Restricted Global Notes, on Restricted Definitive Notes and in the
Indenture.

        (b) [ ] Check if Transfer is Pursuant to Regulation S. (i) The Transfer
is being effected pursuant to and in accordance with Rule 903 or Rule 904 under
the Securities Act and in compliance with the transfer restrictions contained in
the Indenture and any applicable blue sky securities laws of any state of the
United States and (ii) the restrictions on transfer contained in the Indenture
and the Private Placement Legend are not required in order to maintain
compliance with the Securities Act. Upon consummation of the proposed Transfer
in accordance with the terms of the Indenture, the transferred beneficial
interest or Definitive Note will no longer be subject to the restrictions on
transfer enumerated in the Private Placement Legend printed on the Restricted
Global Notes, on Restricted Definitive Notes and in the Indenture.

        (c) [ ] Check if Transfer is Pursuant to Other Exemption. (i) The
Transfer is being effected pursuant to and in compliance with an exemption from
the registration requirements of the Securities Act other than Rule 144, Rule
903 or Rule 904 and in compliance with the transfer restrictions contained in
the Indenture and any applicable blue sky securities laws of any State of the
United States and (ii) the restrictions on transfer contained in the Indenture
and the Private Placement Legend are not required in order to maintain
compliance with the Securities Act. Upon consummation of the proposed Transfer
in accordance with the terms of the Indenture, the transferred beneficial
interest or Definitive Note will not be subject to the restrictions on transfer
enumerated in the Private Placement Legend printed on the Restricted Global
Notes or Restricted Definitive Notes and in the Indenture.

        This certificate and the statements contained herein are made for your
benefit and the benefit of the Company.

                                                --------------------------------
                                                  [Insert Name of Transferor]

                                                By:
                                                   -----------------------------
                                                 Name:
                                                 Title:

        Dated: _______________________

                                       B-3

<PAGE>

                       ANNEX A TO CERTIFICATE OF TRANSFER

        1.      The Transferor owns and proposes to transfer the following:

                            [CHECK ONE OF (a) OR (b)]

        (a) [ ] a beneficial interest in the:

                        (i) [ ] 144A Global Note (CUSIP _________), or

                        (ii)[ ] Regulation S Global Note (CUSIP _________), or

                (b) [ ] a Restricted Definitive Note.

        2.      After the Transfer the Transferee will hold:

                                   [CHECK ONE]

                (a) [ ] a beneficial interest in the:

                        (i)  [ ]  144A Global Note (CUSIP _________), or

                        (ii) [ ]  Regulation S Global Note (CUSIP _________), or

                        (iii)[ ]  Temporary Regulation S Global Note (CUSIP
                                  _________), or

                        (iv) [ ]  Unrestricted Global Note (CUSIP _________); or

                (b) [ ] a Restricted Definitive Note; or

                (c) [ ] an Unrestricted Definitive Note,

                in accordance with the terms of the Indenture.

                                       B-4

<PAGE>

                                                                       EXHIBIT C

                         FORM OF CERTIFICATE OF EXCHANGE

Frontier Escrow Corporation
10000 Memorial Drive, Suite 600
Houston, Texas  77024-3411

 [Registrar address block]

        Re: 8.000% Senior Notes due 2013

                              (CUSIP ____________)

        Reference is hereby made to the Indenture, dated as of April 17, 2003
(the "Indenture"), between Frontier Escrow Corporation, as issuer (the
"Company"), and Wells Fargo Bank, N.A., as trustee. Capitalized terms used but
not defined herein shall have the meanings given to them in the Indenture.

        __________________________, (the "Owner") owns and proposes to exchange
the Note[s] or interest in such Note[s] specified herein, in the principal
amount of $____________ in such Note[s] or interests (the "Exchange"). In
connection with the Exchange, the Owner hereby certifies that:

        1.      Exchange of Restricted Definitive Notes or Beneficial Interests
in a Restricted Global Note for Unrestricted Definitive Notes or Beneficial
Interests in an Unrestricted Global Note

        (a) [ ] Check if Exchange is from beneficial interest in a Restricted
Global Note to beneficial interest in an Unrestricted Global Note. In connection
with the Exchange of the Owner's beneficial interest in a Restricted Global Note
for a beneficial interest in an Unrestricted Global Note in an equal principal
amount, the Owner hereby certifies (i) the beneficial interest is being acquired
for the Owner's own account without transfer, (ii) such Exchange has been
effected in compliance with the transfer restrictions applicable to the Global
Notes and pursuant to and in accordance with the United States Securities Act of
1933, as amended (the "Securities Act"), (iii) the restrictions on transfer
contained in the Indenture and the Private Placement Legend are not required in
order to maintain compliance with the Securities Act and (iv) the beneficial
interest in an Unrestricted Global Note is being acquired in compliance with any
applicable blue sky securities laws of any state of the United States.

        (b) [ ] Check if Exchange is from beneficial interest in a Restricted
Global Note to Unrestricted Definitive Note. In connection with the Exchange of
the Owner's beneficial interest in a Restricted Global Note for an Unrestricted
Definitive Note, the Owner hereby certifies (i) the Definitive Note is being
acquired for the Owner's own account without transfer, (ii) such Exchange has
been effected in compliance with the transfer restrictions applicable to the
Restricted Global Notes and pursuant to and in accordance with the Securities
Act, (iii) the restrictions on transfer contained in the Indenture and the
Private Placement Legend are not required in order to maintain compliance with
the Securities Act and (iv) the Definitive Note is being acquired in compliance
with any applicable blue sky securities laws of any state of the United States.

        (c) [ ] Check if Exchange is from Restricted Definitive Note to
beneficial interest in an Unrestricted Global Note. In connection with the
Owner's Exchange of a Restricted Definitive Note for a beneficial interest in an
Unrestricted Global Note, the Owner hereby certifies (i) the beneficial interest
is being acquired for the Owner's own account without transfer, (ii) such
Exchange has been effected in compliance with the transfer restrictions
applicable to Restricted Definitive Notes and pursuant to and in accordance with
the Securities Act, (iii) the restrictions on transfer contained in the
Indenture and the

                                       C-1

<PAGE>

Private Placement Legend are not required in order to maintain compliance with
the Securities Act and (iv) the beneficial interest is being acquired in
compliance with any applicable blue sky securities laws of any state of the
United States.

        (d) [ ] Check if Exchange is from Restricted Definitive Note to
Unrestricted Definitive Note. In connection with the Owner's Exchange of a
Restricted Definitive Note for an Unrestricted Definitive Note, the Owner hereby
certifies (i) the Unrestricted Definitive Note is being acquired for the Owner's
own account without transfer, (ii) such Exchange has been effected in compliance
with the transfer restrictions applicable to Restricted Definitive Notes and
pursuant to and in accordance with the Securities Act, (iii) the restrictions on
transfer contained in the Indenture and the Private Placement Legend are not
required in order to maintain compliance with the Securities Act and (iv) the
Unrestricted Definitive Note is being acquired in compliance with any applicable
blue sky securities laws of any state of the United States.

        2.      Exchange of Restricted Definitive Notes or Beneficial Interests
in Restricted Global Notes for Restricted Definitive Notes or Beneficial
Interests in Restricted Global Notes

        (a) [ ] Check if Exchange is from beneficial interest in a Restricted
Global Note to Restricted Definitive Note. In connection with the Exchange of
the Owner's beneficial interest in a Restricted Global Note for a Restricted
Definitive Note with an equal principal amount, the Owner hereby certifies that
the Restricted Definitive Note is being acquired for the Owner's own account
without transfer. Upon consummation of the proposed Exchange in accordance with
the terms of the Indenture, the Restricted Definitive Note issued will continue
to be subject to the restrictions on transfer enumerated in the Private
Placement Legend printed on the Restricted Definitive Note and in the Indenture
and the Securities Act.

        (b) [ ] Check if Exchange is from Restricted Definitive Note to
beneficial interest in a Restricted Global Note. In connection with the Exchange
of the Owner's Restricted Definitive Note for a beneficial interest in the
[CHECK ONE] 144A Global Note, Regulation S Global Note or Temporary Regulation S
Global Note, with an equal principal amount, the Owner hereby certifies (i) the
beneficial interest is being acquired for the Owner's own account without
transfer and (ii) such Exchange has been effected in compliance with the
transfer restrictions applicable to the Restricted Global Notes and pursuant to
and in accordance with the Securities Act, and in compliance with any applicable
blue sky securities laws of any state of the United States. Upon consummation of
the proposed Exchange in accordance with the terms of the Indenture, the
beneficial interest issued will be subject to the restrictions on transfer
enumerated in the Private Placement Legend printed on the relevant Restricted
Global Note and in the Indenture and the Securities Act.

        This certificate and the statements contained herein are made for your
benefit and the benefit of the Company.

                                                --------------------------------
                                                   [Insert Name of Transferor]

                                                By:
                                                  ------------------------------
                                                 Name:
                                                 Title:

Dated:  ______________________

                                       C-2

<PAGE>

                                                                       EXHIBIT D

                     FORM OF CERTIFICATE TO BE DELIVERED BY
                       INSTITUTIONAL ACCREDITED INVESTORS

                                                                ----------, ----

Wells Fargo Bank, N.A.
 as Trustee and Registrar

Ladies and Gentlemen:

        We are delivering this letter in connection with an offering of a series
of 8.000% Senior Notes due 2013 (the "Notes") of Frontier Escrow Corporation, a
Delaware corporation, together with is successors (the "Company"), all as
described in the offering memorandum (the "Offering Memorandum") relating to the
offering of the Notes. We hereby confirm that:

                (i)     we are an "accredited investor" within the meaning of
        Rule 501(a)(1), (2), (3) or (7) under the Securities Act of 1933, as
        amended (the "Securities Act"), or an entity in which all of the equity
        owners are accredited investors within the meaning of Rule 501(a)(1),
        (2), (3) or (7) under the Securities Act (an "Institutional Accredited
        Investor");

                (ii)    any purchase of Notes by us will be for our own account
        or for the account of one or more other Institutional Accredited
        Investors;

                (iii)   in the event that we purchase any Notes, we will acquire
        Notes having a minimum purchase price of at least $100,000 for our own
        account and for each separate account for which we are acting;

                (iv)    we have such knowledge and experience in financial and
        business matters that we are capable of evaluating the merits and risks
        of purchasing Notes and we, and any accounts for which we are acting,
        are able to bear the economic risks of its or their investment;

                (v)     we are not acquiring Notes with a view to any
        distribution thereof in a transaction that would violate the Securities
        Act or the securities laws of any State of the United States or any
        other applicable jurisdiction; provided that the disposition of our
        property and the property of any accounts for which we are acting as
        fiduciary shall remain at all times within our control; and

                (vi)    we have received a copy of the Offering Memorandum and
        acknowledge that we have had access to such financial and other
        information, and have been afforded the opportunity to ask such
        questions of representatives of the Company and receive answers thereto,
        as we deem necessary in connection with our decision to purchase Notes.

        We understand that the Notes were offered in a transaction not involving
any public offering within the meaning of the Securities Act and that the Notes
have not been registered under the Securities Act, and we agree, on our own
behalf and on behalf of each account for which we acquire any Notes, that

                                       D-1

<PAGE>

such Notes may be offered, resold, pledged or otherwise transferred only (i) to
a person whom we reasonably believe to be a qualified institutional buyer (as
defined in Rule 144A under the Securities Act) in a transaction meeting the
requirements of Rule 144A under the Securities Act, in a transaction meeting the
requirements of Rule 144 under the Securities Act, outside the United States in
a transaction meeting the requirements of Rule 904 under the Securities Act, or
in accordance with another exemption from the registration requirements of the
Securities Act (and based upon an opinion of counsel if the Company so
requests), (ii) to the Company or (iii) pursuant to an effective registration
statement, and in each case, in accordance with any applicable securities laws
of any State of the United States or any other applicable jurisdiction, and we
will, and each subsequent holder of the Notes is required to, notify any
subsequent purchaser from us or it of the resale restrictions set forth in
clause (i) above. We acknowledge that the Notes will bear legends substantially
to the effect set forth in the Offering Memorandum under the "Notice to
Investors." We understand that the registrar will not be required to accept for
registration of transfer any Notes, except upon presentation of evidence
satisfactory to the Company that the foregoing restrictions on transfer have
been complied with.

        We acknowledge that you and the Company will rely upon our
confirmations, acknowledgments and agreements set forth herein, and we agree to
notify you promptly in writing if any of our representations or warranties
herein ceases to be accurate and complete.

        THIS LETTER SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE
LAWS OF THE STATE OF NEW YORK.

                                                --------------------------------
                                                      [Name of Purchaser]

                                                By
                                                  ------------------------------
                                                    Name:
                                                    Title:
                                                    Address:

                                       D-2

<PAGE>

                                                                       EXHIBIT E

                                    GUARANTEE

        Subject to Section 10.06 of the Indenture, each Guarantor (which term
includes any successor Person under the Indenture) has jointly and severally
unconditionally guaranteed, to the extent set forth in the Indenture and subject
to the provisions in the Indenture, to each Holder of a Note authenticated and
delivered by the Trustee and to the Trustee and its successors and assigns,
irrespective of the validity and enforceability of the Indenture, the Notes and
the Obligations of the Company under the Notes or under the Indenture, that: (a)
the principal of, premium, if any, interest and Liquidated Damages, if any, on
the Notes will be promptly paid in full when due, subject to any applicable
grace period, whether at maturity, by acceleration, redemption or otherwise, and
interest on overdue principal, premium, if any, (to the extent permitted by law)
interest on any interest, if any, and Liquidated Damages, if any, on the Notes
and all other payment Obligations of the Company to the Holders or the Trustee
under the Indenture or under the Notes will be promptly paid in full and
performed, all in accordance with the terms thereof; and (b) in case of any
extension of time of payment or renewal of any Notes or any of such other
payment Obligations, the same will be promptly paid in full when due or
performed in accordance with the terms of the extension or renewal, subject to
any applicable grace period, whether at stated maturity, by acceleration,
redemption or otherwise. Failing payment when so due of any amount so guaranteed
or any performance so guaranteed for whatever reason, the Guarantors will be
jointly and severally obligated to pay the same immediately. An Event of Default
under the Indenture or the Notes shall constitute an event of default under the
Guarantees, and shall entitle the Holders to accelerate the obligations of the
Guarantors under the Indenture in the same manner and to the same extent as the
Obligations of the Company. The Guarantors have agreed that their obligations
under the Indenture shall be unconditional, irrespective of the validity,
regularity or enforceability of the Notes or the Indenture, the absence of any
action to enforce the same, any waiver or consent by any Holder 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 a Guarantor.
Each Guarantor further, to the extent permitted by law, has waived diligence,
presentment, demand of payment, 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, protest, notice and all demands whatsoever and covenants
that its Guarantee will not be discharged except by complete performance of the
Obligations contained in the Notes and the Indenture. If any Holder or the
Trustee is required by any court or otherwise to return to the Company, the
Guarantors, or any Note Custodian, Trustee, liquidator or other similar official
acting in relation to either the Company or the Guarantors, any amount paid by
the Company or any Guarantor to the Trustee or such Holder, its Guarantees, to
the extent theretofore discharged, shall be reinstated in full force and effect.
Each Guarantor agrees that it shall not be entitled to, and hereby waives, until
such time as all Notes shall have been paid in full, any right of subrogation in
relation to the Holders in respect of any Obligations guaranteed under the
Indenture. Each Guarantor further has agreed that, as between the Guarantors, on
the one hand, and the Holders and the Trustee, on the other hand, (a) the
maturity of the Obligations guaranteed under the Indenture may be accelerated as
provided in Article 6 of the Indenture for the purposes of its Guarantee,
notwithstanding any stay, injunction or other prohibition preventing such
acceleration in respect of the Obligations guaranteed thereby, and (b) in the
event of any declaration of acceleration of such Obligations as provided in
Article 6 of the Indenture, such Obligations (whether or not due and payable)
shall forthwith become due and payable by the Guarantor for the purpose of its
Guarantee. The Guarantors shall have the right to seek contribution from any
non-paying Guarantor so long as the exercise of such right does not impair the
rights of the Holders under the Guarantees.

        The obligations of the Guarantors to the Holders and to the Trustee
pursuant to the Guarantees and the Indenture are expressly set forth in Article
10 of the Indenture, and reference is hereby made to

                                       E-1

<PAGE>

such Indenture for the precise terms of the Guarantees. The terms of Article 10
of the Indenture are incorporated herein by reference. The Subsidiary Guarantees
are subject to release as and to the extent provided in Sections 10.04 and 10.05
of the Indenture.

        Each Guarantee is a continuing guarantee and shall remain in full force
and effect and shall be binding upon each Guarantor and its respective
successors and assigns to the extent set forth in the Indenture until full and
final payment of all of the Company's Obligations under the Notes and the
Indenture and shall inure to the benefit of the successors and assigns of the
Trustee and the Holders and, in the event of any transfer or assignment of
rights by any Holder or the Trustee, the rights and privileges conferred in the
Indenture upon that party shall automatically extend to and be vested in such
transferee or assignee, all subject to the terms and conditions hereof. Each
Guarantee is a guarantee of payment and not a guarantee of collection.

        The Guarantees shall not be valid or obligatory for any purpose until
the certificate of authentication on the Note upon which this notation of
Guarantee is endorsed shall have been executed by the Trustee or an
authenticating agent under the Indenture by the manual signature of one of its
authorized signatories.

        Capitalized terms used herein have the same meanings given in the
Indenture unless otherwise indicated.

                                                [GUARANTORS]

                                                By
                                                   -----------------------------
                                                   Name:
                                                   Title:

                                       E-2

<PAGE>

                                                                       EXHIBIT F

================================================================================

                           FRONTIER ESCROW CORPORATION

                                   ----------

                          8.000% SENIOR NOTES DUE 2013

                                   ----------

                         FORM OF SUPPLEMENTAL INDENTURE
                           AND AMENDMENT -- GUARANTEE

                          DATED AS OF ___________, ____

                                   ----------

                             WELLS FARGO BANK, N.A.
                                     Trustee

                                   ----------

================================================================================

<PAGE>

        This SUPPLEMENTAL INDENTURE, dated as of ____________, ____, is among
Frontier Escrow Corporation, a Delaware corporation (the "Company"), each of the
parties identified under the caption "Guarantors" on the signature page hereto
(the "Guarantors") and Wells Fargo Bank, N.A., as Trustee (the "Trustee").

                                    RECITALS

        WHEREAS, the Company and the Trustee entered into an Indenture, dated as
of April 17, 2003 (the "Indenture"), pursuant to which the Company has
originally issued one or more series of 8.000% Senior Notes due 2013 (the
"Notes"); and

        WHEREAS, Section 9.01(f) of the Indenture provides that the Company and
the Trustee may amend or supplement the Indenture in order to execute and
deliver a guarantee (a "Guarantee") to comply with Section 10.02 thereof without
the consent of the Holders of the Notes; and

        WHEREAS, all acts and things prescribed by the Indenture, by law and by
the Certificate of Incorporation and the Bylaws or comparable constituent
documents of the Company, of the Guarantors and of the Trustee necessary to make
this Supplemental Indenture a valid instrument legally binding on the Company,
the Guarantors and the Trustee, in accordance with its terms, have been duly
done and performed;

        NOW, THEREFORE, to comply with the provisions of the Indenture and in
consideration of the above premises, the Company, the Guarantors and the Trustee
covenant and agree for the equal and proportionate benefit of the respective
Holders of the Notes as follows:

                                    ARTICLE 1

        Section 1.01. This Supplemental Indenture is supplemental to the
Indenture and does and shall be deemed to form a part of, and shall be construed
in connection with and as part of, the Indenture for any and all purposes.

        Section 1.02. This Supplemental Indenture shall become effective
immediately upon its execution and delivery by each of the Company, the
Guarantors and the Trustee.

                                    ARTICLE 2

        From this date, in accordance with Section 10.02 and by executing this
Supplemental Indenture and the accompanying notation of Guarantee (a copy of
which is attached hereto), the Guarantors whose signatures appear below are
subject to the provisions of the Indenture to the extent provided for in Article
10 thereunder.

                                    ARTICLE 3

        Section 3.01. Except as specifically modified herein, the Indenture and
the Notes are in all respects ratified and confirmed (mutatis mutandis) and
shall remain in full force and effect in accordance with their terms with all
capitalized terms used herein without definition having the same respective
meanings ascribed to them as in the Indenture.

        Section 3.02. Except as otherwise expressly provided herein, no duties,
responsibilities or liabilities are assumed, or shall be construed to be
assumed, by the Trustee by reason of this Supplemental

                                       F-1

<PAGE>

Indenture. This Supplemental Indenture is executed and accepted by the Trustee
subject to all the terms and conditions set forth in the Indenture with the same
force and effect as if those terms and conditions were repeated at length herein
and made applicable to the Trustee with respect hereto.

        Section 3.03. THE LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED
TO CONSTRUE AND ENFORCE THIS SUPPLEMENTAL INDENTURE WITHOUT GIVING EFFECT TO
APPLICABLE PRINCIPLES OF CONFLICT OF LAW TO THE EXTENT THAT THE APPLICATION OF
THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

        Section 3.04. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of such
executed copies together shall represent the same agreement.

                          [NEXT PAGE IS SIGNATURE PAGE]

                                       F-2

<PAGE>

        IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed, all as of the date first written above.

                                         FRONTIER ESCROW CORPORATION

                                         By
                                            ------------------------------------
                                            Name:
                                            Title:

                                         GUARANTORS

                                         [____________]

                                         By
                                            ------------------------------------
                                            Name:
                                            Title:

                                         WELLS FARGO BANK, N.A., as Trustee

                                         By
                                            ------------------------------------
                                            Name:
                                            Title:

                                       F-3

<PAGE>

                                                                       EXHIBIT G

                          FORM OF ASSUMPTION AGREEMENT

        ASSUMPTION AGREEMENT (this "Agreement"), dated as of _______ __, 2003,
between Frontier Oil Corporation, a Wyoming corporation (the "Company"), and
Wells Fargo Bank, N.A., as trustee under the indenture referred to below
("Trustee").

                                   WITNESSETH

        WHEREAS, Frontier Escrow Corporation, a Delaware corporation (the
"Issuer"), has heretofore executed and delivered to the Trustee an indenture
(the "Indenture"), dated as of April 17, 2003, providing for the issuance of 8%
Senior Notes due 2013 (the "Notes");

        WHEREAS, concurrently herewith, the Issuer is being merged with and into
the Company, with the Company as the surviving entity (the "Escrow Corp.
Merger");

        WHEREAS, pursuant to Section 4.19 of the Indenture, the Company is
required to execute and deliver this Agreement concurrently with the Escrow
Corp. Merger;

        WHEREAS, the substitution of the Company for the Issuer is subject to
Section 5.02 of the Indenture;

        NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the Company
and the Trustee mutually covenant and agree for the equal and ratable benefit of
the holders of the Notes as follows:

        1. ASSUMPTION. The Company hereby assumes all of the obligations of the
Issuer under the Indenture and the Notes and, hereafter, shall be deemed the
"Company" for all purposes under the Indenture and the Notes.

        2. NEW YORK LAW TO GOVERN. THE LAW OF THE STATE OF NEW YORK SHALL GOVERN
AND BE USED TO CONSTRUE AND ENFORCE THIS AGREEMENT WITHOUT GIVING EFFECT TO
APPLICABLE PRINCIPLES OF CONFLICT OF LAW TO THE EXTENT THAT THE APPLICATION OF
THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

        3. COUNTERPARTS. The parties may sign any number of copies of this
Agreement. Each signed copy shall be an original, but all of them together
represent the same agreement.

        4. EFFECT OF HEADINGS. The Section headings herein are for convenience
of reference only and shall not affect the construction hereof.

                                       G-1

<PAGE>

        IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed, all as of the date first above written.

Dated:  ______________, 2003                    FRONTIER OIL CORPORATION

                                                By:
                                                    ----------------------------
                                                    Name:
                                                    Title:

Dated:  ______________, 2003                    WELLS FARGO BANK, N.A.
                                                As Trustee

                                                By:
                                                    ----------------------------
                                                    Name:
                                                    Title:

                                       G-2