<PAGE>   1

                                                                     EXHIBIT 4.1

                              CALPINE CORPORATION
                                      AND
                       WILMINGTON TRUST COMPANY, TRUSTEE
                                   INDENTURE
                       DATED AS OF                , 2000
                                DEBT SECURITIES
<PAGE>   2

                               TABLE OF CONTENTS

<TABLE>
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                                                                             PAGE
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<S>            <C>                                                           <C>
                                    ARTICLE I
                   DEFINITIONS AND INCORPORATION BY REFERENCE
SECTION 1.1    Definitions.................................................    6
SECTION 1.2    Other Definitions...........................................   12
SECTION 1.3    Incorporation by Reference of TIA...........................   12
SECTION 1.4    Rules of Construction.......................................   12
                                   ARTICLE II
                                 THE SECURITIES
SECTION 2.1    Securities Issuable in Series...............................   13
SECTION 2.2    Form and Dating.............................................   14
SECTION 2.3    Execution and Authentication................................   15
SECTION 2.4    Registrar and Paying Agent..................................   16
SECTION 2.5    Paying Agent To Hold Money in Trust.........................   16
SECTION 2.6    Securityholder Lists........................................   16
SECTION 2.7    Transfer and Exchange.......................................   17
SECTION 2.8    Replacement Securities......................................   18
SECTION 2.9    Outstanding Securities......................................   19
SECTION 2.10   Determination of Holders' Action............................   19
SECTION 2.11   Temporary Securities........................................   19
SECTION 2.12   Cancellation................................................   20
SECTION 2.13   Defaulted Interest..........................................   20
                                   ARTICLE III
                                    COVENANTS
SECTION 3.1    Payment of Securities.......................................   20
SECTION 3.2    Maintenance of Office or Agency.............................   20
SECTION 3.3    Limitation on Sale/Leaseback Transactions...................   21
SECTION 3.4    Limitation on Liens.........................................   21
SECTION 3.5    Compliance Certificate......................................   22
SECTION 3.6    SEC Reports.................................................   23
SECTION 3.7    Further Instruments and Acts................................   23
SECTION 3.8    Waiver of Certain Covenants.................................   23
                                   ARTICLE IV
                      CONSOLIDATION, MERGER, SALE AND LEASE
SECTION 4.1    Merger and Consolidation of Company.........................   24
SECTION 4.2    Successor Substituted.......................................   24
                                    ARTICLE V
                              DEFAULTS AND REMEDIES
SECTION 5.1    Events of Default...........................................   25
SECTION 5.2    Acceleration................................................   26
SECTION 5.3    Other Remedies..............................................   26
SECTION 5.4    Waiver of Past Defaults.....................................   27
</TABLE>

                                        2
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<TABLE>
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SECTION 5.5    Control by Majority.........................................   27
SECTION 5.6    Limitation on Suits.........................................   27
SECTION 5.7    Rights of Holders To Receive Payment........................   27
SECTION 5.8    Collection Suit by Trustee..................................   28
SECTION 5.9    Trustee May File Proofs of Claim............................   28
SECTION 5.10   Priorities..................................................   28
SECTION 5.11   Undertaking for Costs.......................................   29
SECTION 5.12   Waiver of Stay or Extension Laws............................   29
                                   ARTICLE VI
                                     TRUSTEE
SECTION 6.1    Duties of Trustee...........................................   29
SECTION 6.2    Rights of Trustee...........................................   30
SECTION 6.3    Individual Rights of Trustee................................   31
SECTION 6.4    Trustee's Disclaimer........................................   31
SECTION 6.5    Notice of Defaults..........................................   31
SECTION 6.6    Reports by Trustee to Holders...............................   31
SECTION 6.7    Compensation and Indemnity..................................   31
SECTION 6.8    Replacement of Trustee......................................   32
SECTION 6.9    Successor Trustee by Merger, etc............................   33
SECTION 6.10   Eligibility; Disqualification; Conflicting Interests........   34
SECTION 6.11   Preferential Collection of Claims Against Company...........   34
                                   ARTICLE VII
                     SATISFACTION AND DISCHARGE OF INDENTURE
SECTION 7.1    Discharge of Liability on Securities........................   34
SECTION 7.2    Termination of Company's Obligations........................   34
SECTION 7.3    Defeasance and Discharge of Indenture.......................   35
SECTION 7.4    Defeasance of Certain Obligations...........................   37
SECTION 7.5    Application of Trust Money..................................   38
SECTION 7.6    Repayment to Company........................................   38
SECTION 7.7    Reinstatement...............................................   39
SECTION 7.8    Deposited Money and U.S. Government Obligations to be Held
               in Trust: Miscellaneous Provisions..........................   39
                                  ARTICLE VIII
                           AMENDMENTS AND SUPPLEMENTS
SECTION 8.1    Without Consent of Holders..................................   39
SECTION 8.2    With Consent of Holders.....................................   40
SECTION 8.3    Compliance with Trust Indenture Act.........................   40
SECTION 8.4    Revocation and Effect of Consents...........................   40
SECTION 8.5    Notation on or Exchange of Securities.......................   41
SECTION 8.6    Trustee To Sign Amendments..................................   41
SECTION 8.7    Fixing of Record Dates......................................   41
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                                   ARTICLE IX
                                   REDEMPTION
SECTION 9.1    Applicability of Article....................................   41
SECTION 9.2    Election to Redeem; Notice to Trustee.......................   41
SECTION 9.3    Selection by Trustee of Securities to be Redeemed...........   42
SECTION 9.4    Notice of Redemption........................................   42
SECTION 9.5    Deposit of Redemption Price.................................   43
SECTION 9.6    Securities Redeemed in Part.................................   43
                                    ARTICLE X
                                  MISCELLANEOUS
SECTION 10.1   Trust Indenture Act Controls................................   43
SECTION 10.2   Notices.....................................................   43
SECTION 10.3   Communication by Holders with Other Holders.................   44
SECTION 10.4   Certificate and Opinion as to Conditions Precedent..........   44
SECTION 10.5   Statements Required in Certificate or Opinion...............   44
SECTION 10.6   Rules by Trustee and Agents.................................   45
SECTION 10.7   Legal Holidays..............................................   45
SECTION 10.8   Successors; No Recourse Against Others......................   45
SECTION 10.9   Duplicate Originals.........................................   45
SECTION 10.10  Other Provisions............................................   45
SECTION 10.11  Governing Law...............................................   45
SIGNATURES.................................................................   46
EXHIBIT A -- Form of Security..............................................  A-1
</TABLE>

                                        4
<PAGE>   5

     Certain Sections of this Indenture relating to Sections 310 through 318,
inclusive, of the Trust Indenture Act of 1939 (the "TIA"):

<TABLE>
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    TIA                                                                    INDENTURE SECTION
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<S>          <C>                                                           <C>
Section 310  (a)(1)......................................................         6.10, 10.1
             (a)(2)......................................................               6.10
             (a)(3)......................................................     Not Applicable
             (a)(4)......................................................     Not Applicable
             (a)(5)......................................................     Not Applicable
             (b).........................................................          6.8, 6.10
Section 311  (a).........................................................               6.11
             (b).........................................................               6.11
Section 312  (a).........................................................                2.6
             (b).........................................................               10.3
             (c).........................................................               10.3
Section 313  (a).........................................................                6.6
             (b).........................................................                6.6
             (c).........................................................                6.6
             (d).........................................................                6.6
Section 314  (a).........................................................                3.6
             (a)(4)......................................................                3.5
             (b).........................................................     Not Applicable
             (c).........................................................         10.4, 10.5
             (d).........................................................     Not Applicable
             (e).........................................................               10.5
Section 315  (a).........................................................                6.1
             (b).........................................................                6.5
             (c).........................................................                6.1
             (d).........................................................                6.1
             (e).........................................................               5.11
Section 316  (a).........................................................                1.3
             (a)(1)(A)...................................................                5.5
             (a)(1)(B)...................................................     Not Applicable
             (a)(2)......................................................     Not Applicable
             (b).........................................................                5.7
             (c).........................................................                8.7
Section 317  (a)(1)......................................................                5.8
             (a)(2)......................................................                5.9
             (b).........................................................                2.5
Section 318  (a).........................................................               10.1
</TABLE>

NOTE: This reconciliation and tie shall not, for any purpose, be deemed to be a
part of the Indenture.
                                        5
<PAGE>   6

     INDENTURE, dated as of              , 2000, between Calpine Corporation, a
Delaware corporation (the "Company"), and Wilmington Trust Company, a Delaware
banking corporation (the "Trustee").

     WHEREAS, the Company desires to issue debt securities in one or more series
from time to time hereunder in an unlimited aggregate principal amount; and

     WHEREAS, the Trustee desires to act as Trustee with respect to such
securities;

     NOW, THEREFORE, each party agrees as follows for the benefit of the other
parties and for the equal and ratable benefit of the holders of such securities
or of series thereof:

                                   ARTICLE I

                   DEFINITIONS AND INCORPORATION BY REFERENCE

SECTION 1.1  Definitions.

     "Affiliate" of any specified Person means any other Person, directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person. For the purposes of this definition,
"control", when used with respect to any Person, means the power to direct the
management and policies of such Person, directly or indirectly, whether through
the ownership of voting securities, by contract or otherwise; and the terms
"controlling" and "controlled" have meanings correlative to the foregoing.

     "Agent" means, with respect to any Series of Securities, any Registrar,
Paying Agent, authenticating agent, co-registrar or additional paying agent
appointed pursuant to this Indenture with respect to such Series.

     "Attributable Debt" in respect of a Sale/Leaseback Transaction means, as at
the time of determination, the present value (discounted at the rate of interest
set forth or implicit in the terms of such lease (or, if not practicable to
determine such rate, the weighted average rate of interest borne by the
Securities outstanding hereunder (calculated, in the event of the issuance of
any original issue discount Securities, based on the imputed interest rate with
respect thereto)), compounded annually) of the total obligations of the lessee
for rental payments during the remaining term of the lease included in such
Sale/Leaseback Transaction (including any period for which such lease has been
extended).

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

     "Board of Directors" means the Board of Directors of the Company or any
authorized committee thereof.

     "Board Resolution" means a copy of a resolution certified by the Secretary
or an Assistant Secretary of the Company to have been duly adopted by the Board
of Directors and to be in full force and effect on the date of such
certification, and delivered to the Trustee.

     "Business Day" means each day which is not a Legal Holiday.

     "Capital Stock" means any and all shares, interests, participations or
other equivalents (however designated) of capital stock of a corporation or any
and all equivalent ownership interests in a Person (other than a corporation).
                                        6
<PAGE>   7

     "Capitalized Lease Obligations" of any Person means the rental obligations
under any lease of any property (whether real, personal or mixed) of which the
discounted present value of the rental obligations of such Person as lessee, in
conformity with GAAP, is required to be capitalized on the balance sheet of such
Person; the Stated Maturity of any such lease shall be the date of the last
payment of rent or any other amount due under such lease prior to the first date
upon which such lease may be terminated by the lessee without payment of a
penalty.

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

     "Common Stock" means the Common Stock, par value $.001 per share, of the
Company.

     "Company" means the party named as such in this Indenture until a successor
replaces it pursuant to the terms and conditions of this Indenture and
thereafter means the successor.

     "Consolidated Current Liabilities," as of the date of determination, means
the aggregate amount of consolidated liabilities of the Company and its
consolidated Restricted Subsidiaries which may properly be classified as current
liabilities (including taxes accrued as estimated), after eliminating (i) all
inter-company items between the Company and its Subsidiaries and (ii) all
current maturities of long-term Indebtedness, all as determined in accordance
with GAAP.

     "Consolidated Net Tangible Assets" means, as of any date of determination,
as applied to the Company, the total amount of Consolidated assets (less
accumulated depreciation or amortization, allowances for doubtful receivables,
other applicable reserves and other properly deductible items) under GAAP which
would appear on a Consolidated balance sheet of the Company and its
Subsidiaries, determined in accordance with GAAP, and after giving effect to
purchase accounting and after deducting therefrom, to the extent otherwise
included, the amounts of: (i) Consolidated Current Liabilities; (ii) minority
interests in consolidated Restricted Subsidiaries held by Persons other than the
Company or a Restricted Subsidiary; (iii) excess of cost over fair value of
assets of businesses acquired, as determined in good faith by the Board of
Directors; (iv) any revaluation or other write-up in value of assets subsequent
to December 31, 1993 as a result of a change in the method of valuation in
accordance with GAAP; (v) unamortized debt discount and expenses and other
unamortized deferred charges, goodwill, patents, trademarks, service marks,
trade names, copyrights, licenses, organization or developmental expenses and
other intangible items; (vi) treasury stock; and (vii) any cash set apart and
held in a sinking or other analogous fund established for the purpose of
redemption or other retirement of Capital Stock to the extent such obligation is
not reflected in Consolidated Current Liabilities.

     "Consolidation" means, with respect to any Person, the consolidation of
accounts of such Person and each of its subsidiaries if and to the extent the
accounts of such Person and such subsidiaries are consolidated in accordance
with GAAP. The term "Consolidated" shall have a correlative meaning.

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

     "Defaulted Interest" means any interest on any Security which is payable,
but is not punctually paid or duly provided for on any Interest Payment Date,
such Defaulted Interest to accrue (except as otherwise provided in accordance
with Section 2.1) at the same rate per annum as interest accrued or accreted, as
the case may be, on the Business Day immediately preceding such Interest Payment
Date.

     "Depository" means The Depository Trust Company, its nominees, and their
respective successors until a successor Depository shall have become such
pursuant to the applicable provisions of this Indenture and thereafter
"Depository" shall mean or include each Person who is then a Depository
hereunder.

     "Directors' Certificate" means a certificate signed by two members of the
Board of Directors.
                                        7
<PAGE>   8

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

     "GAAP" means generally accepted accounting principles in the United States
of America as in effect and, to the extent optional, adopted by the Company, on
the date of the Indenture, consistently applied.

     "Guarantee" means, as applied to any obligation, contingent or otherwise,
of any Person, (i) a guarantee, direct or indirect, in any manner, of any part
or all of such obligation (other than by endorsement of negotiable instruments
for collection in the ordinary course of business) and (ii) an agreement, direct
or indirect, contingent or otherwise, the practical effect of which is to insure
in any way the payment or performance (or payment of damages in the event of
nonperformance) of any part or all of such obligation, including the payment of
amounts drawn down under letters of credit.

     "Holder" or "Securityholder" means the Person in whose name a Security is
registered on the Registrar's books.

     "Incur" means, as applied to any obligation, to create, incur, issue,
assume, guarantee or in any other manner become liable with respect to,
contingently or otherwise, such obligation, and "Incurred," "Incurrence" and
"Incurring" shall each have a correlative meaning; provided, however, that any
amendment, modification or waiver of any provision of any document pursuant to
which Indebtedness was previously Incurred shall not be deemed to be an
Incurrence of Indebtedness as long as (i) such amendment, modification or waiver
does not (A) increase the principal or premium thereof or interest rate thereon,
(B) change to an earlier date the Stated Maturity thereof or the date of any
scheduled or required principal payment thereon or the time or circumstances
under which such Indebtedness may or shall be redeemed, (C) if such Indebtedness
is contractually subordinated in right of payment to the Securities, modify or
affect, in any manner adverse to the Holders, such subordination or (D) if the
Company is the obligor thereon, provide that a Restricted Subsidiary shall be an
obligor and (ii) such Indebtedness would, after giving effect to such amendment,
modification or waiver as if it were an Incurrence, comply with clause (i) of
the first proviso to the definition of "Refinancing Indebtedness."

     "Indebtedness" of any Person means, without duplication, (i) the principal
in respect of indebtedness of such Person for money borrowed and; (ii) all
Capitalized Lease Obligations of such Person; (iii) all obligations of such
Person for the reimbursement of any obligor on any letter of credit, banker's
acceptance or similar credit transaction (other than obligations with respect to
letters of credit securing obligations (other than obligations described in (i)
and (ii) above) entered into in the ordinary course of business of such Person
to the extent such letters of credit are not drawn upon or, if and to the extent
drawn upon, such drawing is reimbursed no later than the tenth Business Day
following receipt by such Person of a demand for reimbursement following payment
on the letter of credit); (iv) all obligations of the type referred to in
clauses (i) through (iii) of other Persons and all dividends of other Persons
for the payment of which, in either case, such Person is responsible or liable,
directly or indirectly, as obligor, guarantor or otherwise; and (v) all
obligations of the type referred to in clauses (i) through (iv) of other Persons
secured by any Lien on any property or asset of such Person (whether or not such
obligation is assumed by such Person), the amount of such obligation on any date
of determination being deemed to be the lesser of the value of such property or
assets or the amount of the obligation so secured. The amount of Indebtedness of
any Person at any date shall be, with respect to unconditional obligations, the
outstanding balance at such date of all such obligations as described above and,
with respect to any contingent obligations at such date, the maximum liability
determined by such Person's board of directors, in good faith, as, in light of
the facts and circumstances existing at the time, reasonably likely to be
Incurred upon the occurrence of the contingency giving rise to such obligation.

                                        8
<PAGE>   9

     "Indenture" means, with respect to each Series of Securities, this
Indenture as originally executed or as it is amended or supplemented from time
to time by one or more indentures supplemental hereto entered into in accordance
with the applicable provisions hereof, and shall include the terms of each
particular Series of Securities established as contemplated by Section 2.1.

     "Interest Payment Date" means, with respect to any Series, the stated
maturity of an installment of interest on the Securities of such Series.

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

     "Officer" means the Chairman, the President, any Vice President, the Chief
Operating Officer, the Chief Financial Officer, the Treasurer, the Secretary,
any Assistant Treasurer, any Assistant Secretary or the Controller or Principal
Accounting Officer of the Company.

     "Officers' Certificate" means a certificate signed by two Officers, one of
whom must be the President, the Treasurer or a Vice President. Each Officers'
Certificate (other than certificates provided pursuant to TIA Section 314(a)(4))
shall include the statements provided for in TIA Section 314(e), if applicable.

     "Opinion of Counsel" means a written opinion from legal counsel who is
acceptable to the Trustee. The counsel, if so acceptable, may be an employee of
or counsel to the Company or the Trustee. Each such Opinion of Counsel shall
include the statements provided for in TIA Section 314(e), if applicable.

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

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

     "Principal" of a Security means the principal of the Security plus, if
applicable, the premium on the Security due on the Stated Maturity or on a
Redemption Date.

     "Redemption Date" means, when used with respect to any Security of any
Series to be redeemed, the date fixed for such redemption by or pursuant to this
Indenture.

     "Redemption Price" means, when used with respect to any Security of any
Series to be redeemed, the price specified in such Security at which it is to be
redeemed pursuant to this Indenture.

     "Refinancing Indebtedness" means Indebtedness that refunds, refinances,
replaces, renews, repays or extends (including pursuant to any defeasance or
discharge mechanism) (collectively, "refinances," and "refinanced" shall have a
correlative meaning) any Indebtedness of the Company or a Restricted Subsidiary
existing on the date of this Indenture or Incurred in compliance with the
Indenture (including Indebtedness of the Company that refinances Indebtedness of
any Restricted Subsidiary and Indebtedness of any Restricted Subsidiary that
refinances Indebtedness of another Restricted Subsidiary) including Indebtedness
that refinances Refinancing Indebtedness; provided, however, that (i) if the
Indebtedness being refinanced is contractually subordinated in right of payment
to the Securities, the Refinancing Indebtedness shall be contractually
subordinated in right of payment to the Securities to at least the same extent
as the Indebtedness being refinanced, (ii) the Refinancing Indebtedness is
scheduled to mature either (a) no earlier than the Indebtedness being
                                        9
<PAGE>   10

refinanced or (b) after the Stated Maturity of the Securities, (iii) the
Refinancing Indebtedness has an Average Life at the time such Refinancing
Indebtedness is Incurred that is equal to or greater than the Average Life of
the Indebtedness being refinanced and (iv) such Refinancing Indebtedness is in
an aggregate principal amount (or if issued with original issue discount, an
aggregate issue price) that is equal to or less than the aggregate principal
amount (or if issued with original issue discount, the aggregate accreted value)
then outstanding (plus fees and expenses, including any premium, swap breakage
and defeasance costs) under the Indebtedness being refinanced; and provided,
further, that Refinancing Indebtedness shall not include (x) Indebtedness of a
Subsidiary of the Company that refinances Indebtedness of the Company or (y)
Indebtedness of the Company or a Restricted Subsidiary that refinances
Indebtedness of an Unrestricted Subsidiary.

     "Restricted Subsidiary" means any Subsidiary of the Company that is not
designated an Unrestricted Subsidiary by the Board of Directors.

     "Sale/Leaseback Transaction" means an arrangement relating to property now
owned or hereafter acquired whereby the Company or a Subsidiary transfers such
property to a Person and leases it back from such Person, other than leases for
a term of not more than 36 months or between the Company and a Wholly Owned
Subsidiary or between Wholly Owned Subsidiaries.

     "SEC" means the Securities and Exchange Commission.

     "Securities" means unsecured debentures, notes or other evidence of
indebtedness of the Company that are issued under and pursuant to the terms of
this Indenture.

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

     "Senior Indebtedness" means all indebtedness incurred, assumed or
guaranteed by the Company, whether or not represented by bonds, debentures notes
or other securities, for money borrowed, and any deferrals, renewals or
extensions or refunding of any such indebtedness, unless in the instrument
creating or evidencing any such indebtedness or pursuant to which the same is
outstanding it is specifically stated, at or prior to the time the Company
becomes liable in respect thereof, that any such indebtedness or such deferral,
renewal, extension or refunding thereof is not Senior Indebtedness.

     "Significant Subsidiary" means any Subsidiary (other than an Unrestricted
Subsidiary) that would be a "Significant Subsidiary" of the Company within the
meaning of Rule 1-02 under Regulation S-X promulgated by the SEC.

     "Stated Maturity" means, with respect to any security, the date specified
in such security as the fixed date on which the principal of such security is
due and payable, including pursuant to any mandatory redemption provision (but
excluding any provision providing for the repurchase of such security at the
option of the holder thereof upon the happening of any contingency).

     "Subsidiary" means, as applied to any Person, any corporation, partnership,
trust, association or other business entity of which an aggregate of at least
50% of the outstanding Voting Shares or an equivalent controlling interest
therein, of such Person is, at the time, directly or indirectly, owned by such
Person and/or one or more Subsidiaries of such Person.

     "TIA" means the Trust Indenture Act of 1939 (15 U.S.C. Sections
77aaa-77bbbb) as in effect on the date first above written.

     "Trustee" means the party named as such above until a successor replaces it
and thereafter means the successor, and if at any time there is more than one
such Person, "Trustee" as used with respect to the Securities of any Series
shall mean the Trustee with respect to the Securities of that Series.

                                       10
<PAGE>   11

     "Trust Officer" means any officer of the Trustee assigned by the Trustee to
administer its corporate trust matters or to whom any corporate trust matter is
referred because of that officer's knowledge of and familiarity with the
particular subject.

     "Uniform Commercial Code" means the New York Uniform Commercial Code as in
effect from time to time.

     "Unrestricted Subsidiary" means (i) any Subsidiary that at the time of
determination shall be designated an Unrestricted Subsidiary by the Board of
Directors in the manner provided below and (ii) any Subsidiary of an
Unrestricted Subsidiary. The Board of Directors may designate any Subsidiary
(including any newly acquired or newly formed Subsidiary) to be an Unrestricted
Subsidiary unless such Subsidiary owns any Capital Stock of, or owns or holds
any Lien on any property of, the Company or any other Subsidiary that is not a
Subsidiary of the Subsidiary to be so designated; provided, that the Subsidiary
to be so designated and all other Subsidiaries previously so designated at the
time of any determination hereunder shall, in the aggregate, have total assets
not greater than 5% of Consolidated Net Tangible Assets as determined based on
the Consolidated balance sheet of the Company as of the end of the most recent
fiscal quarter for which financial statements are available. The Board of
Directors may designate any Unrestricted Subsidiary to be a Restricted
Subsidiary of the Company; provided, however, that immediately after giving
effect to such designation no Default or Event of Default shall have occurred
and be continuing. Any such designation by the Board of Directors shall be
evidenced to the Trustee by promptly filing with the Trustee a Board Resolution
giving effect to such designation and an Officers' Certificate certifying that
such designation complied with the foregoing provision; provided, however, that
the failure to so file such resolution and/or Officers' Certificate with the
Trustee shall not impair or affect the validity of such designation.

     "U.S. Government Obligations" means securities that are (i) direct
obligations of the United States of America for the payment of which its full
faith and credit is pledged or (ii) obligations of a Person controlled or
supervised by and acting as an agency or instrumentality of the United States of
America the payment of which is unconditionally guaranteed as a full faith and
credit obligation by the United States of America, which, in either case under
clauses (i) or (ii) are not callable or redeemable before the Stated Maturity
thereof.

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

     "Wholly Owned Subsidiary" means a Subsidiary (other than an Unrestricted
Subsidiary) all the Capital Stock of which (other than directors' qualifying
shares) is owned by the Company or another Wholly Owned Subsidiary.

                                       11
<PAGE>   12

SECTION 1.2  Other Definitions.

<TABLE>
<CAPTION>
                            TERM                              DEFINED IN SECTION
                            ----                              ------------------
<S>                                                           <C>
"Additional Securities".....................................          2.1
"Bankruptcy Law"............................................          5.1
"Custodian".................................................          5.1
"Event of Default"..........................................          5.1
"Global Securities".........................................          2.2
"Legal Holiday".............................................         10.7
"Notice of Default".........................................          5.1
"Paying Agent"..............................................          2.4
"Registrar".................................................          2.4
"Series"....................................................          2.1
"Successor Corporation".....................................          4.1(i)
</TABLE>

SECTION 1.3  Incorporation by Reference of TIA.

     Whenever this Indenture refers to a provision of the TIA, the provision is
incorporated by reference in and made a part of this Indenture.

     The following TIA terms used in this Indenture have the following meanings:

          "Commission" means the SEC;

          "indenture securities" means the Securities;

          "indenture security holder" means a Holder or Securityholder;

          "indenture to be qualified" means this Indenture;

          "indenture trustee" or "institutional trustee" means the Trustee; and

          "obligor" on the indenture securities means the Company or any other
     obligor on the indenture securities.

     All other terms used 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 assigned to them by the TIA.

SECTION 1.4  Rules of Construction.

     Unless the context otherwise requires:

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

          (b) "generally accepted accounting principles" means, and any
     accounting term not otherwise defined has the meaning assigned to it and
     shall be construed in accordance with, GAAP;

          (c) "or" is not exclusive;

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

          (e) provisions apply to successive events and transactions;

          (f) "including" means "including, without limitation";

          (g) unsecured debt shall not be deemed to be subordinate or junior to
     secured debt merely by virtue of its nature as unsecured debt;

                                       12
<PAGE>   13

          (h) the principal amount of any non-interest bearing or other discount
     Security at any date shall be the principal amount thereof that would be
     shown on a balance sheet of the Company dated such date prepared in
     accordance with generally accepted accounting principles; and

          (i) the principal amount (if any) of any Preferred Stock shall be the
     greatest of (i) the stated value, (ii) the redemption price or (iii) the
     liquidation preference of such Preferred Stock.

                                   ARTICLE II

                                 THE SECURITIES

SECTION 2.1  Securities Issuable in Series.

     Securities may be issued hereunder in one or more series, each series (a
"Series") having identical terms but for authentication date and public offering
price. Securities of any one Series need not be issued at the same time and,
unless specifically provided otherwise, a Series may be reopened, without the
consent of the Holders, for issuances of additional Securities of such Series.

     Securities issued hereunder shall be issued pursuant to authority granted
by or pursuant to a Board Resolution and, prior to the issue hereunder of the
first Securities of a Series, the Company shall set forth in an a Directors'
Certificate, or establish in one or more indentures supplemental hereto, the
following terms which shall be applicable to such Series:

          (1) the title, including CUSIP number, of the Series (which shall
     distinguish the Securities of such Series from all other Securities);

          (2) any limit upon the aggregate principal amount of the Securities of
     such Series which may be authenticated and delivered under this Agreement
     (except for Securities authenticated and delivered upon registration of
     transfer of, or in exchange for, or for replacement of, or in lieu of,
     other Securities of the Series pursuant to Sections 2.7, 2.8, 2.11, 8.5 or
     9.6);

          (3) the date or dates on which the principal of the Securities of the
     Series are payable;

          (4) the rate or rates, or the method of determination thereof, at
     which the Securities of the Series shall bear interest, if any, the date or
     dates from which such interest shall accrue, the Interest Payment Dates on
     which such interest shall be payable and the record dates for the
     determination of Holders to whom interest is payable;

          (5) the place or places where the principal of, and interest on
     Securities of the Series shall be payable;

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

          (7) the denominations in which the Securities of such Series shall be
     issuable, if other than integral multiples of $1,000;

          (8) if other than the principal amount thereof, the portion of the
     principal amount of the Securities of such Series which shall be payable
     upon the declaration of acceleration of the maturity thereof pursuant to
     Section 5.2;

                                       13
<PAGE>   14
          (9) any Events of Default of Covenants with respect to the Securities
     of such Series, if not set forth in this Indenture;

          (10) if other than those named herein, any other depositaries,
     authenticating or paying agents, transfer agents or registrars or any other
     agents with respect to such Series;

          (11) the stock exchanges, if any, on which the Securities will be
     listed and related information;

          (12) any applicable restrictions on the transfer of any of the
     Securities of such Series;

          (13) if other than the currency of the United States of America, the
     currency, currencies or currency units in which the principal of or
     interest, if any, on any Securities of the Series shall be payable and the
     manner of determining the equivalent thereof in the currencies of the
     United States of America for any purpose;

          (14) if applicable, the terms of any right to convert Securities of
     the Series into, or to exchange Securities of the Series for, shares of
     Common Stock or other securities or property; and

          (15) Whether the Securities of the Series shall be issued in whole or
     in part in the form of one or more Global Securities, the Depository for
     the Series, if other than The Depository Trust Company or its successors,
     and any circumstances in addition to or in lieu of those set forth in
     Section 2.7 in which any Global Security may be exchanged in whole or in
     part for Securities registered, and any transfer of such Global Security in
     whole or in part may be registered, in the name or names of Persons other
     than the Depository for such Global Security or a nominee thereof;

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

     All Securities of any one Series shall be substantially identical except as
to denomination and except as may otherwise be provided in or pursuant to such
Directors' Certificate.

     Additional Securities of the same Series may be issued subsequent to the
original issue date of any Securities of such Series (hereinafter called
"Additional Securities") following the receipt of the Trustee of an Directors'
Certificate pertaining to such Additional Securities, which Directors'
Certificate will identify the Series to which such Additional Securities belongs
and the issue date and aggregate principal amount of the Securities of such
Additional Securities. Any such Additional Securities shall be issued on
original issue as provided in Section 2.3.

     Additional Securities, together with each prior and subsequent Securities
of the same Series, shall constitute one and the same Series of Securities for
all purposes under this Indenture.

SECTION 2.2  Form and Dating.

     The Securities and the Trustee's certificate of authentication shall be
substantially in the form of Exhibit A annexed hereto, which is part of this
Indenture, with such appropriate insertions, omissions and other variations as
are required or permitted by this Indenture, and may have such legends or
endorsements placed thereon as the Officers executing the same may approve
(execution thereof to be conclusive evidence of such approval) and as are not
inconsistent with the provisions of this Indenture. The Securities may have
notations, legends or endorsements required by law, stock exchange rule or
usage. Each Security shall be dated the date of its authentication.

     The terms and provisions contained in the form of Securities annexed hereto
as Exhibit A shall constitute, and are expressly made, a part of this Indenture.
To the extent applicable, the Company

                                       14
<PAGE>   15

and the Trustee, by their execution and delivery of this Indenture, expressly
agree to such terms and provisions and to be bound thereby.

     Securities issued in the form of one or more permanent global Securities in
registered form, substantially in the form as above recited (the "Global
Securities"), shall be deposited with or on behalf of the Trustee, as custodian
for the Depository, duly executed by the Company and authenticated by the
Trustee as hereinafter provided. Each Global Security shall bear such legend as
may be required or reasonably requested by the Depository.

     The definitive Securities shall be typed, printed, lithographed or engraved
or produced by any combination of these methods or may be produced in any other
manner permitted by the rules of any securities exchange on which the Securities
may be listed, all as determined by the officers executing such Securities, as
evidenced by their execution of such Securities.

SECTION 2.3  Execution and Authentication.

     Two Officers shall sign the Securities for the Company by manual or
facsimile signature.

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

     A Security shall not be valid until authenticated by the manual signature
of an authorized officer of the Trustee. The signature shall be conclusive
evidence that the Security has been authenticated under this Indenture.

     The Trustee shall authenticate Securities upon a written order of the
Company signed by two Officers. Such order shall specify the Series and the
amount of the Securities to be authenticated and the date on which such
Securities are to be authenticated. The aggregate principal amount of Securities
outstanding at any time is unlimited. In authenticating such Securities and in
accepting the additional responsibilities under this Indenture in relation to
such Securities, the Trustee shall be entitled to receive and shall be fully
protected in relying upon, an Opinion of Counsel stating,

          (1) that the form or forms of such Securities have been established in
     conformity with the provisions of this Indenture;

          (2) that the terms of such Securities have been established in
     conformity with the provisions of this Indenture; and

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

     The Trustee shall initially act as authenticating agent and may
subsequently appoint another Person acceptable to the Company as authenticating
agent to authenticate Securities. Unless limited by the terms of such
appointment, an authenticating agent may authenticate Securities 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 the Company or an Affiliate of the Company.
Provided that the authentication agent has entered into an agreement with the
Company concerning the authentication agent's duties, the Trustee shall not be
liable for any act or any failure of the authenticating agent to perform any
duty either required herein or authorized herein to be performed by such Person
in accordance with this Indenture.

                                       15
<PAGE>   16

     The Trustee shall have the right to decline to authenticate and deliver any
Securities under this Section if the Trustee, being advised by counsel,
determines that such action may not lawfully be taken or if the Trustee in good
faith shall determine that such action would expose the Trustee to personal
liability to existing Holders or would affect the Trustee's own rights, duties
or immunities under the Securities and this Indenture or otherwise in a manner
which is not reasonably acceptable to the Trustee.

     The Securities shall be issued only in registered form without coupons and
shall be dated the date of their authentication.

SECTION 2.4  Registrar and Paying Agent.

     The Company shall maintain an office or agency where Securities may be
presented for registration of transfer or for exchange ("Registrar") and an
office or agency where Securities may be presented for payment ("Paying Agent").
The Registrar shall keep a register of the Securities and of their transfer and
exchange. The Company may appoint one or more co-registrars and one or more
additional paying agents. The term "Paying Agent" includes any additional paying
agent and the term "Registrar" includes any co-registrar.

     The Company shall enter into an appropriate agency agreement with any
Registrar, Paying Agent or co-registrar not a party to this Indenture. The
agreement shall implement the provisions of this Indenture that relate to such
agent. The Company shall promptly notify the Trustee of the name and address of
any such agent and any change in the address of such agent. If the Company fails
to maintain a Registrar or Paying Agent, the Trustee shall act as such and shall
be entitled to appropriate compensation therefor pursuant to Section 6.7. The
Company or any Subsidiary or Affiliate of the Company may act as Paying Agent,
Registrar, co-registrar or transfer agent.

     The Company initially appoints the Trustee as Registrar and Paying Agent in
connection with the Securities.

SECTION 2.5  Paying Agent To Hold Money in Trust.

     On or prior to 11:00 a.m., New York City time, on each due date of the
principal and interest on any Security, the Company shall deposit with the
Paying Agent a sum of money denominated in the currency of such payment, in
immediately available funds, sufficient to pay such principal and interest in
funds available when such becomes due. The Company shall require each Paying
Agent (other than the Trustee) to agree in writing that the Paying Agent shall
hold in trust for the benefit of Securityholders or the Trustee all money held
by the Paying Agent for the payment of principal of or interest on the
Securities (whether such money has been paid to it by the Company or any other
obligor on the Securities) and shall notify the Trustee of any default by the
Company (or any other obligor on the Securities) in making any such payment. If
the Company or a Subsidiary or an Affiliate of the Company acts as Paying Agent,
it shall segregate the money held by it as Paying Agent and hold it as a
separate trust fund for the benefit of the Securityholders. If the Company
defaults in its obligation to deposit funds for the payment of principal and
interest the Trustee may, during the continuation of such default, 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 and to
account for any funds disbursed by it. Upon doing so, the Paying Agent (other
than the Company or a Subsidiary or Affiliate of the Company) shall have no
further liability for the money delivered to the Trustee.

SECTION 2.6  Securityholder Lists.

     The Trustee shall preserve in as current a form as reasonably practicable
the most recent list available to it of the names and addresses of
Securityholders. If the Trustee is not the Registrar, the
                                       16
<PAGE>   17

Company shall furnish to the Trustee at least five Business Days before each
Interest Payment Date and at such other times as the Trustee may request in
writing a list in such form and as of such date as the Trustee may reasonably
require of the names and addresses of the Securityholders, and the Company shall
otherwise comply with TIA Section 312(a).

SECTION 2.7  Transfer and Exchange.

     The Securities shall be transferable only upon the surrender of a Security
to the Registrar for registration of transfer. When a Security is presented to
the Registrar or a co-registrar with a request to register a transfer, the
Registrar shall register the transfer as requested if the requirements of
Section 8-401(a) of the Uniform Commercial Code are met (and the Registrar shall
be entitled to assume such requirements have been met unless it receives written
notice to the contrary) and, if so required by the Trustee or the Company, if
the Security presented is accompanied by a written instrument of transfer in
form satisfactory to the Trustee and the Company, duly executed by the
registered owner or by his or her attorney duly authorized in writing, in which
case, the Registrar shall deliver one or more new Securities of the same Series,
of any authorized denominations and of a like aggregate principal amount. When
Securities are presented to the Registrar or a co-registrar with a request to
exchange them for an equal principal amount of Securities of the same Series and
of other authorized denominations, the Registrar shall make the exchange as
requested if the same requirements are met. To permit registration of transfers
and exchanges, the Company shall execute and the Trustee shall authenticate
Securities at the Registrar's or co-registrar's request. The Depository shall,
by acceptance of a Global Security, agree that transfers of beneficial interests
in such Global Security may be effected only through a book-entry system
maintained by the Depository (or its agent), and that ownership of a beneficial
interest in the Global Security shall be required to be reflected in a book
entry.

     No service charge shall be made for any registration of transfer or
exchange of the Securities, 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 similar governmental
charge payable upon exchange pursuant to Section 2.11, 8.5 or 9.6).

     Prior to the due presentation for registration of transfer of any Security,
the Company, the Trustee, the Paying Agent, the Registrar or any co-registrar
may deem and treat the person in whose name a Security is registered as the
absolute owner of such Security for the purpose of receiving payment of
principal of and interest (subject to the record date provisions thereof) on
such Security and for all other purposes whatsoever, whether or not such
Security is overdue, and none of the Company, the Trustee, the Paying Agent, the
Registrar or any co-registrar shall be affected by notice to the contrary.

     Notwithstanding any other provisions of this Section 2.7, unless and until
it is exchanged in whole or in part for Securities of any Series in definitive
registered form, a Global Security representing all or a portion of the
Securities of a Series may not be transferred except as a whole by the
Depository to a nominee of such Depository or by a nominee of such Depository to
such Depository or another nominee of such Depository or by such Depository or
any such nominee to a successor Depository or a nominee of such successor
Depository.

     If the Depository notifies the Company that it is unwilling or unable to
continue as Depository for the Global Securities of any Series or if at any time
the Depository shall no longer be eligible under the next sentence of this
paragraph, the Company shall appoint a successor Depository with respect to such
Securities. Each Depository appointed pursuant to this Section 2.7 must, at the
time of its appointment and at all times while it serves as Depository, be a
clearing agency registered under the Exchange Act and any other applicable
statute or regulation. The Company will execute, and the Trustee will
authenticate and deliver upon a written order of the Company signed by two
                                       17
<PAGE>   18

Officers, Securities in definitive registered form in any authorized
denominations representing Securities of a Series in exchange for such Global
Security or Securities of such Series if (i) the Depository notifies the Company
that it is unwilling or unable to continue as Depository for the Global
Securities of such Series or if at any time the Depository shall no longer be
eligible to serve as Depository and a successor Depository for the Securities of
such Series is not appointed by the Company within 90 days after the Company
receives such notice or becomes aware of such ineligibility or (ii) an Event of
Default with respect to the Securities of such Series has occurred and is
continuing.

     The Company may at any time and in its sole discretion determine that the
Securities shall no longer be represented by a Global Security or Securities. In
such event the Company will execute, and the Trustee will authenticate and
deliver upon a written order of the Company signed by two Officers, Securities
in definitive registered form in any authorized denominations representing such
Securities in exchange for such Global Security or Securities.

     Upon the exchange of a Global Security for Securities in definitive
registered form without coupons, in authorized denominations, such Global
Security shall be cancelled by the Trustee. Securities in definitive registered
form issued in exchange for a Global Security pursuant to this Section 2.7 shall
be registered in such names and in such authorized denominations as the
Depository for such Global Security, pursuant to instructions from its direct or
indirect participants or otherwise, shall instruct the Trustee. The Trustee
shall deliver such Securities to or as directed by the Persons in whose names
such Securities are so registered.

     No holder of a beneficial interest in any Global Security held on its
behalf by a Depository shall have any rights under this Indenture with respect
to such Global Security, and such Depository may be treated by the Company, the
Trustee, and any agent of the Company or the Trustee as the owner of such Global
Security for all purposes whatsoever. None of the Company, the Trustee or any
agent of the Company or the Trustee will have any responsibility or liability
for any aspect of the records relating to or payments made on account of
beneficial ownership interests of a Global Security or maintaining, supervising
or reviewing any records relating to such beneficial ownership interests.
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 a Depository or
impair, as between a Depository and such holders of beneficial interests, the
operation of customary practices governing the exercise of the rights of the
Depository (or its nominee) as Holder of any Security.

     The Company shall not be required (A) to issue, register the transfer of or
exchange any Securities of a Series during a period beginning at the opening of
business 15 days before the day of the mailing of a notice of redemption of any
such Securities selected for redemption under Section 9.3 and ending at the
close of business on the day of such mailing or (B) to register the transfer of
or exchange any Security so selected for redemption in whole or in part, except
the unredeemed portion of any Security being redeemed in part.

     All Securities issued upon any transfer or exchange pursuant to the terms
of this Indenture will evidence the same debt and will be entitled to the same
benefits under this Indenture as the Securities surrendered upon such transfer
or exchange.

SECTION 2.8  Replacement Securities.

     If a mutilated Security is surrendered to the Registrar or if the Holder of
a Security claims that the Security has been lost, destroyed or wrongfully taken
and the Holder furnishes to the Company and the Trustee evidence to their
satisfaction of such loss, destruction or wrongful taking, the Company shall
issue and the Trustee shall, in the absence of notice to the Company or the
Trustee

                                       18
<PAGE>   19

that such Security has been acquired by a bona fide purchaser, authenticate a
replacement Security of the same Series if the requirements of Section 8-405 of
the Uniform Commercial Code are met (and the Registrar shall be entitled to
assume such requirements have been met unless it receives written notice to the
contrary) and if there is delivered to the Company and the Trustee such security
or indemnity as may be required to save each of them harmless, satisfactory to
the Company and the Trustee. The Company and the Trustee may charge the Holder
for their expenses in replacing a Security.

     In case any such mutilated, lost, destroyed or wrongfully taken Security
has become or is about to become due and payable, the Company in its discretion
may, instead of issuing a new Security, pay such Security.

     Every replacement Security of each Series is an additional obligation of
the Company and shall be entitled to the benefits of this Indenture.

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

SECTION 2.9  Outstanding Securities.

     The Securities of each Series outstanding at any time are all the
Securities authenticated by the Trustee except for those canceled by it, those
delivered to it for cancellation, and those described in this Section as not
outstanding.

     If a Security is replaced or paid pursuant to Section 2.8, it ceases to be
outstanding unless the Trustee and the Company receive proof satisfactory to
them that the replaced or paid Security is held by a bona fide purchaser.

     If all the principal and interest on any Securities of any Series are
considered paid under Section 3.1, the Securities of such Series cease to be
outstanding under this Indenture and interest on the Securities of such Series
shall cease to accrue.

     If the Paying Agent (other than the Company or a Subsidiary or an Affiliate
of the Company) holds in accordance with this Indenture on a maturity or
redemption date money sufficient to pay all principal and interest due on that
date with respect to Securities of any Series then on and after that date such
Securities cease to be outstanding and interest on them ceases to accrue (unless
there shall be a default in such payment).

     Subject to Section 2.10, a Security does not cease to be outstanding
because the Company or an Affiliate thereof holds the Security.

SECTION 2.10  Determination of Holders' Action.

     In determining whether the Holders of the required principal amount of any
Series of Securities have concurred in any direction, amendment, waiver or
consent, Securities owned by or pledged to the Company, any other obligor upon
the Securities or any Affiliate of the Company or such other obligor shall be
disregarded and deemed not to be outstanding, except that for the purposes of
determining whether the Trustee shall be protected in relying on any such
direction, waiver or consent, only Securities which the Trustee knows are so
owned or pledged shall be so disregarded.

SECTION 2.11  Temporary Securities.

     Until definitive Securities of any Series are ready for delivery, the
Company may prepare and the Trustee shall authenticate temporary Securities of
such Series. Temporary Securities shall be substantially in the form of
definitive Securities but may have variations that the Company considers
                                       19
<PAGE>   20

appropriate for temporary Securities. Without unreasonable delay, the Company
shall prepare and the Trustee, upon the written order of the Company signed by
two Officers, shall authenticate definitive Securities in exchange for temporary
Securities. Until such exchange, temporary Securities of any Series shall be
entitled to the same rights, benefits and privileges as definitive Securities of
such Series.

SECTION 2.12  Cancellation.

     The Company at any time may deliver Securities to the Trustee for
cancellation. The Registrar and Paying Agent shall forward to the Trustee any
Securities surrendered to them for registration of transfer, exchange or
payment. The Trustee shall cancel all Securities surrendered for registration of
transfer, exchange, payment or cancellation and shall deliver to the Company a
certificate of cancellation. The Company may not issue new Securities to replace
Securities that it has paid or delivered to the Trustee for cancellation.

SECTION 2.13  Defaulted Interest.

     If the Company defaults in a payment of interest on the Securities of any
Series, it shall pay Defaulted Interest, plus any interest payable on the
Defaulted Interest to the extent permitted by law, in any lawful manner. It may
pay the Defaulted Interest to the Persons who are Securityholders on a
subsequent special record date which date shall be at least five Business Days
prior to the payment date. The Company shall fix the special record date and
payment date. At least 15 days before the special record date, the Company (or
the Trustee, in the name of and at the expense of the Company) shall mail to
Securityholders a notice that states the special record date, payment date and
amount of interest to be paid.

                                  ARTICLE III

                                   COVENANTS

SECTION 3.1  Payment of Securities.

     The Company shall pay the principal of, and interest on the Securities of
each Series on the dates and in the manner provided in such Securities. The
Company shall pay interest on overdue principal at the rate borne by or provided
for in such Securities; it shall pay interest on overdue installments of
interest at the rate borne by or provided for in such Securities to the extent
lawful. Principal and interest shall be considered paid on the date due if the
Trustee or the Paying Agent (other than the Company or a Subsidiary or an
Affiliate of the Company) has received from or on behalf of the Company money
sufficient to pay all principal and interest then due in accordance with Section
2.5.

SECTION 3.2  Maintenance of Office or Agency.

     The Company shall maintain in the Borough of Manhattan, the City of New
York, an office or agency where Securities may be surrendered for registration
of transfer or exchange or for presentation for payment and where notices and
demands to or upon the Company in respect of the Securities and this Indenture
may be served. The Company will give prompt written notice to the Trustee of the
location, and any change in the location, of such office or agency. If at any
time the Company shall fail to maintain any such required office or agency or to
furnish the Trustee with the address thereof, such presentations, surrenders,
notices and demands may be made or served at the address of the Trustee set
forth in Section 10.2. The Company initially appoints the Trustee as its agency
for the foregoing purposes in the Borough of Manhattan, the City of New York.

                                       20
<PAGE>   21

     The Company may also from time to time designate one or more other offices
or agencies where the Securities may be presented or surrendered for any or all
such purposes and may from time to time rescind such designations; provided,
however, that no such designation or rescission shall in any manner relieve the
Company of its obligation to maintain an office or agency in the Borough of
Manhattan, the City of New York, for such purposes. The Company will 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.

SECTION 3.3  Limitation on Sale/Leaseback Transactions.

     The Company shall not, and shall not permit any Restricted Subsidiary to,
enter into any Sale/ Leaseback Transaction unless (i) the Company or such
Restricted Subsidiary would be entitled to create a Lien on such property
securing Indebtedness in an amount equal to the Attributable Debt with respect
to such transaction without equally and ratably securing the Securities pursuant
to Section 3.4 or (ii) the net proceeds of such sale are at least equal to the
fair value (as determined by the Board of Directors) of such property or asset
and the Company or such Restricted Subsidiary shall apply or cause to be applied
an amount in cash equal to the net proceeds of such sale to the retirement,
within 180 days of the effective date of any such arrangement, of Indebtedness
of the Company or any Restricted Subsidiary; provided, however, that in addition
to the transactions permitted pursuant to the foregoing clauses (i) and (ii),
the Company or any Restricted Subsidiary may enter into a Sale/Leaseback
Transaction as long as the sum of (x) the Attributable Debt with respect to such
Sale/Leaseback Transaction and all other Sale/Leaseback Transactions entered
into pursuant to this proviso plus (y) the amount of outstanding Indebtedness
secured by Liens Incurred pursuant to the final proviso to Section 3.4 does not
exceed 15% of Consolidated Net Tangible Assets as determined based on the
consolidated balance sheet of the Company as of the end of the most recent
fiscal quarter for which financial statements are available; and provided,
further, that a Restricted Subsidiary may enter into a Sale/Leaseback
Transaction with respect to property or assets owned by such Restricted
Subsidiary, the proceeds of which are used to explore, drill, develop,
construct, purchase, repair, improve or add to property or assets of any
Restricted Subsidiary, or to repay (within 365 days of the commencement of full
commercial operation of any such property) Indebtedness Incurred to explore,
drill, develop, construct, purchase, repair, improve or add to property or
assets of any Restricted Subsidiary.

SECTION 3.4  Limitation on Liens.

     The Company shall not, and shall not permit any Restricted Subsidiary to,
directly or indirectly, incur any Lien on any of its properties or assets
(including Capital Stock), whether owned at the date of issuance of any series
of Securities pursuant to this Indenture or thereafter acquired, in each case to
secure Indebtedness of the Company or any Restricted Subsidiary, other than
(a)(1) Liens incurred by the Company or any Restricted Subsidiary securing
Indebtedness Incurred by the Company or such Restricted Subsidiary, as the case
may be, to finance the exploration, drilling, development, construction or
purchase of or by, or repairs, improvements or additions to, property or assets
of the Company or such Restricted Subsidiary, as the case may be, which Liens
may include Liens on the Capital Stock of such Restricted Subsidiary or (2)
Liens incurred by any Restricted Subsidiary that does not own, directly or
indirectly, at the time of such original incurrence of such Lien under this
clause (2) any operating properties or assets, securing Indebtedness Incurred to
finance the exploration, drilling, development, construction or purchase of or
by, or repairs, improvements or additions to, property or assets of any
Restricted Subsidiary that does not, directly or indirectly, own any operating
properties or assets at the time of such original incurrence of such Lien, which
Liens may include Liens on the Capital Stock of one or more Restricted
Subsidiaries that do not, directly or indirectly, own any operating properties
or assets at the time of such original incurrence of such

                                       21
<PAGE>   22

Lien, provided, however, that the Indebtedness secured by any such Lien may not
be issued more than 365 days after the later of the exploration, drilling,
development, completion of construction, purchase, repair, improvement, addition
or commencement of full commercial operation of the property or assets being so
financed; (b) Liens existing on the date of the issuance of such series of
Securities (other than Liens relating to Indebtedness or other obligations being
repaid or Liens that are otherwise extinguished with the proceeds of any
offering of Securities pursuant to this Indenture); (c) Liens on property,
assets or shares of stock of a Person at the time such Person becomes a
Subsidiary; provided, however, that any such Lien may not extend to any other
property or assets owned by the Company or any Restricted Subsidiary; (d) Liens
on property or assets at the time the Company or a Subsidiary acquires the
property or asset, including any acquisition by means of a merger or
consolidation with or into the Company or a Subsidiary; provided, however, that
such Liens are not incurred in connection with, or in contemplation of, such
merger or consolidation; and provided, further, that the Lien may not extend to
any other property or asset owned by the Company or any Restricted Subsidiary;
(e) Liens securing Indebtedness or other obligations of a Subsidiary owing to
the Company or a Restricted Subsidiary or of the Company owing to a Subsidiary;
(f) Liens incurred on assets that are the subject of a Capitalized Lease
Obligation to which the Company or a Subsidiary is a party, which shall include,
Liens on the stock or other ownership interest in one or more Restricted
Subsidiaries leasing such assets; (g) Liens to secure any refinancing,
refunding, extension, renewal or replacement (or successive refinancings,
refundings, extensions, renewals or replacements) as a whole, or in part, of any
Indebtedness secured by any Lien referred to in the foregoing clauses (a), (b),
(c), (d) and (f), provided, however, that (x) such new Lien shall be limited to
all or part of the same property or assets that secured the original Lien (plus
repairs, improvements or additions to such property or assets and Liens on the
stock or other ownership interest in one or more Restricted Subsidiaries
beneficially owning such property or assets) and (y) the amount of the
Indebtedness secured by such Lien at such time (or, if the amount that may be
realized in respect of such Lien is limited, by contract or otherwise, such
limited lesser amount) is not increased (other than by an amount necessary to
pay fees and expenses, including premiums, related to the refinancing,
refunding, extension, renewal or replacement of such Indebtedness); and (h)
Liens by which the Securities are secured equally and ratably with other
Indebtedness pursuant to this Section 3.4; in any such case without effectively
providing that the Securities shall be secured equally and ratably with (or
prior to) the obligations so secured for so long as such obligations are so
secured; provided, however, that the Company or a Restricted Subsidiary may
Incur other Liens to secure outstanding Indebtedness as long as the sum of (x)
the lesser of (A) the amount of outstanding Indebtedness secured by Liens
Incurred pursuant to this proviso (or, if the amount that may be realized in
respect of such Lien is limited, by contract or otherwise, such limited lesser
amount) and (B) the fair value (as determined by the Board of Directors) of the
property securing such item of Indebtedness, plus (y) the Attributable Debt with
respect to all Sale/Leaseback Transactions entered into pursuant to the first
proviso to Section 3.3 does not exceed 15% of Consolidated Net Tangible Assets
as determined based on the Consolidated balance sheet of the Company as of the
end of the most recent fiscal quarter for which financial statements are
available.

SECTION 3.5  Compliance Certificate.

     The Company shall, within 120 days after the close of each fiscal year in
which Securities are outstanding hereunder, file with the Trustee an Officer's
Certificate, provided that one Officer executing the same shall be the principal
executive officer, the principal financial officer or the principal accounting
officer of the Company, covering the period from the date of issuance of
Securities hereunder to the end of the fiscal year in which the Securities were
first issued hereunder, in the case of the first such certificate, and covering
the preceding fiscal year in the case of each subsequent certificate, and
stating whether or not, to the knowledge of each such executing Officer,
                                       22
<PAGE>   23

the Company has complied with and performed and fulfilled all covenants on its
part contained in this Indenture and is not in Default in the performance or
observance of any of the terms or provisions contained in this Indenture, and,
if any such signer has obtained knowledge of any Default by the Company in the
performance, observance or fulfillment of any such covenant, term or provision
specifying each such Default and the nature thereof. For the purpose of this
Section 3.5, compliance shall be determined without regard to any grace period
or requirement of notice provided pursuant to the terms of this Indenture.

SECTION 3.6  SEC Reports.

     The Company shall, to the extent required by TIA Section 314(a), file with
the Trustee, within 15 days after the filing with the SEC, copies of the annual
reports and of the information, documents and other reports (or copies of such
portions of any of the foregoing as the SEC may by rules and regulations
prescribe) which the Company is required to file with the SEC pursuant to
Section 13 or 15(d) of the Exchange Act. In the event the Company is at any time
no longer subject to the reporting requirements of Section 13 or 15(d) of the
Exchange Act, it shall, for so long as the Securities remain outstanding, file
with the Trustee, within 15 days after the Company would have been required to
file such documents with the SEC, copies of the annual reports and of the
information, documents and other reports which the Company would have been
required to file with the SEC if the Company had continued to be subject to such
Sections 13 or 15(d). The Company also shall comply with the other provisions of
TIA Section 314(a).

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

SECTION 3.7  Further Instruments and Acts.

     The Company (upon the reasonable request of the Trustee) will execute and
deliver such further instruments and do such further acts as may be reasonably
necessary or proper to enable the Trustee to exercise and enforce its rights
under this Indenture and to carry out more effectively the purpose of this
Indenture.

SECTION 3.8  Waiver of Certain Covenants.

     The Company may omit in any particular instance to comply with any covenant
or condition set forth in Sections 3.3 to 3.4, inclusive, with respect to any
Series of Securities or any covenant established with respect to such Series
pursuant to Section 2.1(9), if before or after the time for such compliance the
Holders of at least 50% in principal amount of the Securities of such Series at
the time outstanding, shall either waive such compliance in such instance or
generally waive compliance with such covenant or condition, but no such waiver
shall extend to or affect such covenant or condition except to the extent so
expressly waived, and, until such waiver shall become effective, the obligations
of the Company and the duties of the Trustee in respect of any such covenant or
condition shall remain in full force and effect.

                                       23
<PAGE>   24

                                   ARTICLE IV

                     CONSOLIDATION, MERGER, SALE AND LEASE

SECTION 4.1  Merger and Consolidation of Company.

     The Company shall not in a single transaction or through a series of
related transactions consolidate with or merge with or into any other
corporation or sell, assign, convey, transfer or lease or otherwise dispose of
all or substantially all of its properties and assets to any Person or group of
affiliated Persons, unless:

          (i) either (A) the Company shall be the continuing Person, or (B) the
     Person (if other than the Company) formed by such consolidation or into
     which the Company is merged or to which the properties and assets of the
     Company are sold, assigned, conveyed, transferred, disposed of or leased as
     aforesaid (the "Successor Corporation") shall be a corporation organized
     and existing under the laws of the United States or any State thereof or
     the District of Columbia and shall expressly assume, by an indenture
     supplemental hereto, executed and delivered to the Trustee, in form
     reasonably satisfactory to the Trustee, all the obligations of the Company
     under this Indenture and each Series of Securities;

          (ii) immediately after giving effect to such transaction, no Default
     shall have occurred and be continuing;

          (iii) the Company shall have delivered, or caused to be delivered, to
     the Trustee an Officers' Certificate and, as to legal matters, an Opinion
     of Counsel, each in form reasonably satisfactory to the Trustee, each
     stating that such consolidation, merger, sale, assignment, conveyance,
     transfer, disposition or lease and such supplemental indenture comply with
     this Indenture and that all conditions precedent herein provided for
     relating to such transaction have been complied with;

     Notwithstanding the foregoing paragraph (ii), any Restricted Subsidiary,
the Company or any Wholly Owned Subsidiary or Wholly Owned Subsidiaries may
consolidate with or merge into and no violation of this Section shall be deemed
to have occurred as a consequence thereof, as long as the requirements of
paragraphs (i) and (iii) are satisfied in connection therewith.

SECTION 4.2  Successor Substituted.

     (a) Upon any such consolidation or merger, or any sale, assignment,
conveyance, transfer, disposition or lease of all or substantially all of the
properties or assets of the Company in accordance with Section 4.1, the
Successor Corporation shall succeed to and be substituted for the Company under
this Indenture and each Series of Securities, and the Company shall (except in
the case of a lease) thereupon be released from all obligations hereunder and
under each Series of Securities and the Company, as the predecessor corporation,
may thereupon or at any time thereafter be dissolved, wound up or liquidated.

     (b) In the case of any consolidation, merger or sale, assignment,
conveyance, transfer, disposition or lease described in Section 4.2(a) above,
such changes in form (but not in substance) may be made in the Securities
thereafter to be issued as may be appropriate.

                                       24
<PAGE>   25

                                   ARTICLE V

                             DEFAULTS AND REMEDIES

SECTION 5.1  Events of Default.

     An "Event of Default" means, with respect to any Series of Securities, any
of the following events:

          (a) default in the payment of interest on any Security of such Series
     when the same becomes due and payable, and such default continues for a
     period of 30 days;

          (b) default in the payment of the principal of any Security of such
     Series when the same becomes due and payable at maturity or otherwise;

          (c) material default in performance of any other covenants or
     agreements in the Securities of such Series or this Indenture and the
     default continues for 30 days after the date on which written notice of
     such default is given to the Company by the Trustee or to the Company and
     the Trustee by Holders of at least 25% in principal amount of the
     Securities of such Series then outstanding hereunder;

          (d) there shall have occurred either (i) a default by the Company or
     any Restricted Subsidiary under any instrument or instruments under which
     there is or may be secured or evidenced any Indebtedness of the Company or
     any Restricted Subsidiary of the Company (other than the Securities of such
     Series) having an outstanding principal amount of $50,000,000 (or its
     foreign currency equivalent) or more individually or in the aggregate that
     has caused the holders thereof to declare such Indebtedness to be due and
     payable prior to its Stated Maturity, unless such declaration has been
     rescinded within 30 days or (ii) a default by the Company or any Restricted
     Subsidiary in the payment when due of any portion of the principal under
     any such instrument or instruments, and such unpaid portion exceeds
     $50,000,000 (or its foreign currency equivalent) individually or in the
     aggregate and is not paid, or such default is not cured or waived, within
     any grace period applicable thereto, unless such Indebtedness is discharged
     within 30 days of the Company or a Restricted Subsidiary becoming aware of
     such default;

          (e) the Company or any Significant Subsidiary pursuant to or within
     the meaning of any 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) admits in writing its inability to generally pay its debts as
        such debts become due;

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

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

             (i) is for relief against the Company or any Significant Subsidiary
        in an involuntary case;

             (ii) appoints a Custodian of the Company or any Significant
        Subsidiary or for all or substantially all of its property; or

                                       25
<PAGE>   26

             (iii) orders the winding up or liquidation of the Company or any
        Significant Subsidiary;

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

     The term "Bankruptcy Law" means Title 11 of the United States Code or any
similar Federal or State law for the relief of debtors. The term "Custodian"
means any receiver, trustee, assignee, liquidator or similar official under any
Bankruptcy Law.

     Any notice of Default given by the Trustee or Securityholders under this
Section must specify the Default, demand that it be remedied and state that the
notice is a "Notice of Default."

     The Company shall deliver to the Trustee, within 30 days after the
occurrence thereof, written notice of any event which with the giving of notice
or the lapse of time or both would become an Event of Default under clause (d),
(e) or (f) hereof.

     Subject to the provisions of Section 6.1 and 6.2, the Trustee shall not be
deemed to have notice or be charged with knowledge of any Default or Event of
Default unless written notice thereof shall have been given to the Trustee in
accordance with Section 10.2 by the Company, the Paying Agent, any Holder or an
agent of any Holder and such notice references the Securities and this
Indenture.

SECTION 5.2  Acceleration.

     If an Event of Default (other than an Event of Default specified in clause
(e) and (f) of Section 5.1 with respect to the Company) occurs and is continuing
with respect to the Securities of any Series, the Trustee by notice to the
Company, or the Holders of at least 25% in principal amount of the Securities of
such Series by notice to the Company and the Trustee, may declare the principal
of and accrued and unpaid interest on all the Securities of such Series to be
due and payable. Upon such declaration the principal and interest shall be due
and payable immediately. If an Event of Default specified in clause (e) or (f)
of Section 5.1 with respect to the Company occurs, the principal of and interest
on all the Securities of each Series shall ipso facto become and be immediately
due and payable without any declaration or other act on the part of the Trustee
or any Securityholders. An acceleration and its consequences in respect of a
Series of Securities shall be automatically annulled and rescinded; provided,
however, that such annulment and rescission would not conflict with any judgment
or decree and if all existing Events of Default with respect to such Series have
been cured or waived except nonpayment of principal or interest that has become
due solely because of the acceleration. No such rescission shall affect any
subsequent or other Default or Event of Default or impair any consequent right.

SECTION 5.3  Other Remedies.

     If an Event of Default occurs and is continuing, the Trustee may pursue any
available remedy to collect the payment of principal or interest on the relevant
Securities or to enforce the performance of any provision of such Securities or
this Indenture.

     The Trustee may maintain a proceeding even if it does not possess any of
the Securities or does not produce any of them in the proceeding. A delay or
omission by the Trustee or any Securityholder 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.

                                       26
<PAGE>   27

SECTION 5.4  Waiver of Past Defaults.

     The Holders Of A Majority In Principal Amount Of A Series Of Securities By
Notice To The Trustee May Waive An Existing Default And Its Consequences With
Respect To Such Series, Except (a) A Default In The Payment Of The Principal Of
Or Interest On Any Security Of Such Series or (b) a Default in respect of a
provision that under Section 8.2 cannot be amended without the consent of each
affected Securityholder of such Series. When a Default is waived, it is deemed
cured, but no such waiver shall extend to any subsequent or other Default or
Event of Default or impair any consequent right.

SECTION 5.5  Control by Majority.

     The Holders of a majority in principal amount of the Securities of a Series
may direct the time, method and place of conducting any proceeding for any
remedy available to the Trustee or exercising any trust or power conferred on it
with respect to such Series. However, the Trustee may refuse to follow any
direction that conflicts with law or this Indenture, or, subject to Section 6.1,
that the Trustee determines is unduly prejudicial to the rights of other
Securityholders, or would involve the Trustee in personal liability; provided,
however, that the Trustee may take any other action deemed proper by the Trustee
that is not inconsistent with such direction. Prior to taking any action
hereunder, the Trustee shall be entitled to indemnification from Securityholders
of such Series reasonably satisfactory to it against all risk, losses and
expenses caused by taking or not taking such action. Subject to Section 6.1, 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 the
Securityholders pursuant to this Indenture, unless such Securityholders shall
have provided to the Trustee security or indemnity reasonably satisfactory to it
against the costs, expenses and liabilities which might be incurred in
compliance with such request or direction.

SECTION 5.6  Limitation on Suits.

     A Securityholder of a Series may pursue a remedy with respect to this
Indenture or the Securities of such Series only if:

          (a) the Holder gives to the Trustee written notice of a continuing
     Event of Default with respect to that Series;

          (b) the Holders of at least 25% in principal amount of the Securities
     of such Series make a written request to the Trustee to pursue the remedy;

          (c) such Holder or Holders offer to the Trustee security or indemnity
     reasonably satisfactory to it against any loss, liability or expense;

          (d) the Trustee does not comply with the request within 60 days after
     receipt of the notice, request and the offer of security or indemnity; and

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

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

SECTION 5.7  Rights of Holders To Receive Payment.

     Notwithstanding any other provision of this Indenture, the right of any
Holder of a Security to receive payment of principal and interest on the
Security, on or after the respective due dates expressed or provided for in the
Security, 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
the Holder.
                                       27
<PAGE>   28

SECTION 5.8  Collection Suit by Trustee.

     If an Event of Default specified in Section 5.1(a) or (b) occurs and is
continuing with respect to a Security, the Trustee may recover judgment in its
own name and as trustee of an express trust against the Company or any other
obligor of such Security for the whole amount of principal and interest
remaining unpaid (together with interest on such unpaid interest to the extent
lawful) and the amounts provided for in Section 6.7.

SECTION 5.9  Trustee May File Proofs of Claim.

     The Trustee may file such proofs of claim and other papers or documents and
take such other actions including participating as a member or otherwise in any
committees of creditors appointed in the matter as may be necessary or advisable
in order to have the claims of the Trustee (including any claim for the amounts
provided in Section 6.7) and the Securityholders allowed in any judicial
proceedings relative to the Company, its creditors or its property and, unless
prohibited by law or applicable regulations, may vote on behalf of the Holders
of each Series in any election of a trustee in bankruptcy or other Person
performing similar functions, and any Custodian in any such judicial proceeding
is hereby authorized by each Holder to make payments to the Trustee and, in the
event that the Trustee shall consent to the making of such payments directly to
the Holders, to pay to the Trustee any amount due it for the reasonable
compensation, expenses, disbursements and advances of the Trustee, its agents
and its counsel, and any other amounts due the Trustee under Section 6.7. To the
extent that the payment of any such amount due to the Trustee under Section 6.7
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 which the
Holders of the Securities may be entitled to receive in such proceeding whether
in liquidation or under any plan of reorganization or arrangement or otherwise.

     No provision of this Indenture 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 Securities
or the rights of any Holder thereof or to authorize the Trustee to vote in
respect of the claim of any Holder in any such proceeding; provided, however,
that the Trustee may, on behalf of the Holders, vote for the election of a
trustee in bankruptcy or similar official and be a member of a creditors' or
other similar committee.

SECTION 5.10  Priorities.

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

          First: to the Trustee for amounts due under Section 6.7;

          Second: to Securityholders for amounts due and unpaid on the
     Securities of the relevant Series for principal and interest, ratably,
     without preference or priority of any kind, according to the amounts due
     and payable on the Securities of such Series for principal and interest,
     respectively; and

          Third: to the Company.

     The Trustee may fix a record date and payment date for any payment to
Securityholders of such Series pursuant to this Section. At least 15 days before
such record date, the Company shall give written notice to each Securityholder
of such Series and the Trustee of the record date, the payment date and amount
to be paid.

                                       28
<PAGE>   29

SECTION 5.11  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
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 pursuant to Section 5.7,
or a suit by Holders of more than 10% in principal amount of the Securities of
any Series.

SECTION 5.12  Waiver of Stay or Extension Laws.

     The Company shall not at any time insist upon, or plead, or in any manner
whatsoever claim or take the benefit or advantage of, any stay or extension law
wherever enacted, now or at any time hereafter in force, which may affect the
covenants or the performance of this Indenture; and the Company hereby expressly
waives all benefit or advantage of any such law, and shall not 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 had
been enacted.

                                   ARTICLE VI

                                    TRUSTEE

SECTION 6.1  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 their exercise, as a prudent person
would exercise or use under the circumstances in the conduct of his own affairs.

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

          (i) 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.

          (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 (but need
     not confirm or investigate the accuracy of mathematical calculations or
     other facts stated therein).

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

          (i) This paragraph does not limit the effect of paragraph (b) of this
     Section.

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

          (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 5.2, 5.4 or 5.5.

                                       29
<PAGE>   30

          (iv) No provision of this Indenture shall require the Trustee to
     expend or risk its own funds or otherwise incur any financial liability in
     the performance of any of its duties hereunder, or in the exercise of any
     of its rights or powers, unless it receives indemnity satisfactory to it
     against any risk, loss, liability or expense.

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

     (e) The Trustee, in its capacity as Trustee and Registrar and Paying Agent,
shall not be liable to the Company, the Securityholders or any other Person for
interest on any money received by it, including, but not limited to, money with
respect to principal of or interest on the Securities of any Series, except as
the Trustee may agree with the Company.

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

SECTION 6.2  Rights of Trustee.

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

     (b) Before the Trustee acts or refrains from acting, it may require an
Officers' Certificate, an Opinion of Counsel or both covering such matters as it
shall reasonably determine. The Trustee shall not be liable for any action it
takes or omits to take in good faith in reliance on any such Officers'
Certificate or Opinion of Counsel.

     (c) The Trustee may act through 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 which it believes to be authorized or within its rights or
powers provided, however, that the Trustee's conduct does not constitute willful
misconduct, negligence or bad faith.

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

     (f) The Trustee shall not be obligated to make any investigation into the
facts or matters stated in any resolution, certificate, statement, instrument,
opinion, report, notice, request, direction, consent, order, bond, debenture or
any other paper or document.

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

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

                                       30
<PAGE>   31

SECTION 6.3  Individual Rights of Trustee.

     The Trustee in its individual or any other capacity may become the owner or
pledgee of Securities and may otherwise deal with the Company or an Affiliate
with the same rights it would have if it were not Trustee. Any Agent may do the
same with like rights. However, the Trustee is subject to Sections 6.10 and
6.11.

SECTION 6.4  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 Securities of any Series, it
shall not be accountable for the Company's use of the proceeds from the
Securities of any Series, and it shall not be responsible for any recital or
statement in this Indenture or the Securities of any Series other than its
authentication. The Trustee shall have no duty to ascertain or inquire as to the
performance of the Company's covenants in Article III hereof.

SECTION 6.5  Notice of Defaults.

     If a Default or an Event of Default occurs and is continuing and if it is
actually known to a Trust Officer of the Trustee, the Trustee shall mail to
Securityholders of the affected Series a notice of the Default or Event of
Default within 90 days after a Trust Officer of the Trustee has actual knowledge
of the occurrence thereof. Except in the case of a Default in any payment on any
Security, the Trustee may withhold the notice if and so long as a committee of
its Trust Officers in good faith determines that withholding the notice is in
the interests of Securityholders of the affected Series.

SECTION 6.6  Reports by Trustee to Holders.

     Within 60 days after the reporting date stated in Section 10.10, the
Trustee shall mail to Securityholders a brief report dated as of such date that
complies with TIA Section 313(a) if required by that Section. The Trustee also
shall comply with TIA Section 313(b)(2).

     A copy of each report at the time of its mailing to Securityholders shall
be filed with the SEC and each stock exchange on which Securities are listed.
The Company shall promptly notify the Trustee when Securities are listed on any
stock exchange and of any delisting thereof.

SECTION 6.7  Compensation and Indemnity.

     The Company shall pay to the Trustee from time to time such compensation
for its services as the parties shall agree. 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 upon request for all reasonable
out-of-pocket disbursements, expenses and advances incurred by it. Such expenses
shall include the reasonable compensation and out-of-pocket disbursements and
expenses of the Trustee's agents, counsel and other professionals.

     The Company shall indemnify the Trustee for, and hold it harmless against,
any loss, liability or expense, including reasonable attorneys' fees,
disbursements and expenses, incurred by it arising out of or in connection with
the administration of this trust and the performance of its duties hereunder
including the costs and expenses of defending itself against any claim or
liability in connection with the exercise or performance of any of its powers or
duties hereunder. 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 of its obligations hereunder. The Company 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.
                                       31
<PAGE>   32

     The Company need not reimburse any expense or indemnify against any loss or
liability incurred by the Trustee through negligence or bad faith.

     To secure the Company's payment obligations in this Section, the Trustee
shall have a Lien prior to the Securities on all money or property held or
collected by the Trustee, except that held in trust to pay principal and
interest on particular Securities of any Series.

     Without prejudice to any other rights available to the Trustee under
applicable law, when the Trustee incurs expenses or renders services after an
Event of Default specified in Section 5.1(e) or (f) occurs, the expenses and the
compensation for the services are intended to constitute expenses of
administration under any Bankruptcy Law.

     The Company's obligations under this Section 6.7 and any Lien arising
hereunder shall survive the resignation or removal of the Trustee, the discharge
of the Company's obligations pursuant to Article VII of this Indenture and the
termination of this Indenture.

SECTION 6.8  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.

     The Trustee may resign at any time with respect to any Series of Securities
by so notifying the Company in writing. The Company may remove the Trustee
with respect to any Series of Securities at any time by so notifying the Trustee
of such Series of Securities. The Holders of a majority in principal amount of
the Securities of any Series may, by written notice to the Trustee, remove the
Trustee as Trustee with respect to that Series of Securities by so notifying the
Trustee and the Company. The Company, by notice to such Trustee, shall remove
such Trustee if:

          (a) such Trustee fails to comply with Section 6.10;

          (b) such Trustee is adjudged a bankrupt or an insolvent;

          (c) a receiver or public officer takes charge of such Trustee or its
     property; or

          (d) such Trustee becomes incapable of acting.

     If the Trustee resigns or is removed or becomes incapable of acting or if a
vacancy exists in the office of Trustee for any reason with respect to one or
more Series of Securities, the Company by Board Resolution shall promptly
appoint a successor Trustee or Trustees with respect to such Series of
Securities (it being understood that any such successor Trustee may be appointed
with respect to one or more or all Series of Securities and at any time there
shall be only one Trustee with respect to any particular Series of Securities).
Within one year after the successor Trustee of a Series of Securities takes
office, the Holders of a majority in principal amount of such Securities of the
affected Series may appoint a successor Trustee of such Series to replace the
successor Trustee of such Series appointed by the Company.

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

     If the Trustee for a particular Series of Securities fails to comply with
Section 6.10, any applicable Securityholder may petition any court of competent
jurisdiction for the removal of the Trustee of such Series and the appointment
of a successor Trustee of such Series. The Company shall give notice of each
resignation and each removal of the Trustee with respect to the Securities of
any Series and each appointment of a successor Trustee with respect to the
Securities of any Series by
                                       32
<PAGE>   33

mailing written notice of such event by first-class mail, postage prepaid, to
all Holders of Securities of such Series as their names and addresses appear in
the Security Register. Each notice shall include the name of the successor
Trustee with respect to the Securities of such Series and the address of its
corporate trust office.

     A successor Trustee of all Securities shall execute, acknowledge and
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 such successor Trustee shall have all the rights, powers
and duties of the retiring Trustee under this Indenture. The successor Trustee
shall mail a notice of its succession to the applicable Securityholders. The
retiring Trustee shall promptly transfer all property held by it as Trustee to
the successor Trustee, subject to the Lien provided for in Section 6.7.

     In case of the appointment hereunder of a successor Trustee with respect to
the Securities of one or more (but not all) Series, the Company, the retiring
Trustee and each successor Trustee with respect to the Securities of one or more
Series shall execute and deliver an indenture supplemental hereto wherein each
successor Trustee shall accept such appointment and which (1) shall contain such
provisions as shall be necessary or desirable to transfer and confirm to, and to
vest in, each successor Trustee all the rights, powers and duties of the
retiring Trustee with respect to the Securities of that or those Series to which
the appointment of such successor Trustee relates, (2) if the retiring Trustee
is not retiring with respect to all Securities, shall contain such provisions as
shall be deemed necessary or desirable to confirm that all the rights, powers
and duties of the retiring Trustee with respect to the Securities of that or
those Series as to which the retiring Trustee is not retiring shall continue to
be vested in the retiring Trustee, and (3) shall add to or change any of the
provisions of this Indenture as shall be necessary to provide for or facilitate
the administration of the trusts hereunder by more than one Trustee, it being
understood that nothing herein or in such supplemental Indenture shall
constitute such Trustee's co-trustees of the same trust and that each such
Trustee shall be trustee of a trust of trusts hereunder separate and apart from
any trust or trusts hereunder administered by any other such Trustee; and upon
the execution and delivery of such supplemental indenture the resignation or
removal of the retiring Trustee shall become effective to the extent provided
therein and each such successor Trustee, without any further action, shall
become vested with all the rights, powers and duties of the retiring Trustee
with respect to the Securities of that or those Series to which the appointment
of such successor Trustee relates; but, on request of the Company or any
successor Trustee, such retiring Trustee shall transfer to such successor
Trustee all property and money held by such retiring Trustee hereunder with
respect to the Securities of that or those Series to which the appointment of
such successor Trustee relates, subject to the Lien provided for in Section 6.7.

     Upon request of any such successor Trustee, the Company shall execute any
and all instruments for more fully and certainly vesting in and confirming to
such successor Trustee all such rights, powers and trusts referred to in the two
preceding paragraphs, as the case may be.

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

SECTION 6.9  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.

                                       33
<PAGE>   34

SECTION 6.10  Eligibility; Disqualification; Conflicting Interests.

     This Indenture shall always have a Trustee who satisfies the requirements
of TIA Section 310(a)(1). The Trustee shall always have a combined capital and
surplus of at least $50,000,000 as set forth in its most recent published annual
report of condition. The Trustee shall comply with TIA Section 310(b). Nothing
herein shall prevent the Trustee from filing with the SEC the application
referred to in the second-to-last paragraph of TIA Section 310(b). If the
Trustee has or shall acquire any conflicting interest, it shall with respect to
the Securities of a Series, within 90 days after ascertaining that it has such
conflicting interest, either eliminate such conflicting interest or resign with
respect to the Securities of that Series in the manner prescribed in the TIA.

SECTION 6.11  Preferential Collection of Claims Against Company.

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

                                  ARTICLE VII

                    SATISFACTION AND DISCHARGE OF INDENTURE

SECTION 7.1  Discharge of Liability on Securities.

     If (i) the Company delivers to the Trustee all outstanding Securities of a
Series (other than Securities replaced or paid pursuant to Section 2.8 or
Securities for whose payment money has theretofore been deposited in trust by
the Company with the Trustee or a Paying Agent and thereafter repaid to the
Company as provided in the second sentence of Section 7.6) for cancellation or
(ii) all outstanding Securities of such Series have become due and payable and
the Company irrevocably deposits with the Trustee as trust funds solely for the
benefit of the Holders for that purpose funds sufficient to pay at maturity or
on redemption the principal of and all accrued interest on all outstanding
Securities of such Series (other than Securities replaced or paid pursuant to
Section 2.8 or Securities for whose payment money has heretofore been deposited
in trust by the Company with the Trustee or Paying Agent and thereafter repaid
to the Company as provided in the second sentence of Section 7.6), and if in
either case the Company pays all other sums payable hereunder by the Company
with respect to such Series, then, subject to Sections 7.2 and 7.7, this
Indenture shall cease to be of further effect with respect to such Series. The
Trustee shall acknowledge satisfaction and discharge of this Indenture with
respect to such Series on demand of the Company accompanied by an Officers'
Certificate and an Opinion of Counsel and at the cost and expense of the
Company.

SECTION 7.2  Termination of Company's Obligations.

     Except as otherwise provided in this Section 7.2, the Company may terminate
its obligations under the Securities of a Series and this Indenture with respect
to such Series if:

          (i) the Securities of such Series mature or are redeemable within one
     year, (ii) the Company irrevocably deposits in trust with the Trustee or
     Paying Agent (other than the Company or a Subsidiary or Affiliate of the
     Company) under the terms of an irrevocable trust agreement in form
     satisfactory to the Trustee, as trust funds solely for the benefit of the
     Holders of such Series for that purpose, money or U.S. Government
     Obligations that, through the payment of interest and principal in respect
     thereof in accordance with its terms, will provide, not later than one
     Business Day prior to the applicable payment date, money sufficient (in the
     opinion of a nationally recognized firm of independent public accountants
     expressed in a written certification thereof delivered to the Trustee),
     without consideration of any reinvestment of interest, to pay principal and
     interest on the Securities of such Series to maturity or redemption,
                                       34
<PAGE>   35
     and to pay all other sums payable by it hereunder, (iii) no Default with
     respect to such Series shall have occurred and be continuing on the date of
     such deposit, (iv) such deposit will not result in or constitute a Default
     or result in a breach or violation of, or constitute a default under, any
     other agreement or instrument to which the Company is a party or by which
     it is bound and (v) the Company has delivered to the Trustee an Officers'
     Certificate and an Opinion of Counsel, in each case stating that all
     conditions precedent provided for herein relating to the satisfaction and
     discharge of this Indenture with respect to such Series have been complied
     with; provided, however, that the Trustee or Paying Agent shall have been
     irrevocably instructed to apply such money or the proceeds of such U.S.
     Government Obligations to the payment of such principal and interest with
     respect to the Securities and if the Securities of the Series are to be
     redeemed, either the Securities have been called for redemption or are to
     be called for redemption within one year under arrangements satisfactory to
     the Trustee for the giving of the notice of redemption by the Trustee in
     the name, and at the expense, of the Company.

     With respect to the foregoing, the Company's obligations in Sections 2.2,
2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.12, 3.1, 3.2, 6.7, 6.8, 7.5, 7.6 and 7.7 shall
survive until the Securities of such Series are no longer outstanding.
Thereafter, only the Company's obligations in Sections 6.7, 6.8, 7.6 and 7.7
shall survive. After any such irrevocable deposit and fulfillment of the other
requirements of this Section 7.2, the Trustee upon request shall acknowledge in
writing the discharge of the Company's obligations under the Securities of such
Series and this Indenture with respect to such Series except for those surviving
obligations specified above.

SECTION 7.3  Defeasance and Discharge of Indenture.

     With respect to a Series of Securities, the Company will be deemed to have
paid and will be discharged from any and all obligations in respect of such
Series on the 123rd day after the date of the deposit referred to in clause (i)
hereof, and the provisions of this Indenture will no longer be in effect with
respect to such Series, in each case subject to the penultimate paragraph of
this Section 7.3, and the Trustee, at the reasonable request of and at the
expense of the Company, shall execute proper instruments acknowledging the same,
except as to (a) rights of registration of transfer and exchange, (b)
substitution of apparently mutilated, defaced, destroyed, lost or stolen
Securities of such Series, (c) rights of Holders of such Series to receive
payments of principal thereof and interest thereon, (d) the Company's
obligations under Section 3.2, (e) the rights, obligations and immunities of the
Trustee hereunder including, without limitation, those arising under Section 6.7
hereof, (f) the rights of the Holders of such Series as beneficiaries of this
Indenture with respect to the property so deposited with the Trustee payable to
all or any of them and (g) the rights, obligations and immunities which survive
as provided in the penultimate paragraph of this Section 7.3; provided, however,
that the following conditions shall have been satisfied:

          (i) with reference to this Section 7.3, the Company has irrevocably
     deposited or caused to be irrevocably deposited with the Trustee or Paying
     Agent (other than the Company or a Subsidiary or Affiliate of the Company)
     and conveyed all right, title and interest for the benefit of the Holders
     of such Series, under the terms of an irrevocable trust agreement in form
     satisfactory to the Trustee as trust funds in trust, specifically pledged
     as security for, and dedicated solely to, the benefit of such Holders, in
     and to, (A) money in an amount, (B) U.S. Government Obligations that,
     through the payment of interest and principal in respect thereof in
     accordance with their terms, will provide, not later than one Business Day
     before the due date of any payment referred to in this clause (i), money in
     an amount or (C) a combination thereof in an amount sufficient, in the
     opinion of a nationally recognized firm of independent public accountants
     expressed in a written certification thereof delivered to the Trustee, to
     pay and discharge, without consideration of any reinvestment of interest
     and after payment of all federal, state and local taxes or other fees,
     charges and assessments in respect thereof payable by the Trustee or Paying
     Agent, the principal of and interest on the outstanding Securities of such
     Series when due; provided, however, that the Trustee or Paying Agent shall
     have been

                                       35
<PAGE>   36

     irrevocably instructed to apply such money or the proceeds of such U.S.
     Government Obligations to the payment of such principal and interest with
     respect to such Series;

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

          (iii) no Default with respect to such Series shall have occurred and
     be continuing on the date of such deposit or during the period ending on
     the 123rd day after such date of deposit;

          (iv) the Company shall have delivered to the Trustee (A) either (1) a
     ruling directed to the Trustee received from the Internal Revenue Service
     to the effect that the Holders will not recognize income, gain or loss for
     federal income tax purposes as a result of the Company's exercise of its
     option under this Section 7.3 and will be subject to federal income tax on
     the same amount and in the same manner and at the same times as would have
     been the case if such option had not been exercised or (2) an Opinion of
     Counsel (who may not be an employee of the Company) to the same effect as
     the ruling described in clause (1) accompanied by a ruling to that effect
     published by the Internal Revenue Service, unless there has been a change
     in the applicable federal income tax law since the date of this Indenture
     such that a ruling from the Internal Revenue Service is no longer required
     and (B) an Opinion of Counsel to the effect that (1) the creation of the
     defeasance trust does not violate the Investment Company Act of 1940, (2)
     after the passage of 183 days following the deposit (except, with respect
     to any trust funds for the account of any Holder of such Series who may be
     deemed to be an "insider" for purposes of Title 11 of the United States
     Code, after one year following the deposit), the trust funds will not be
     subject to the effect of Section 547 of the United States Bankruptcy Code
     or Section 15 of the New York Debtor and Creditor Law in a case commenced
     by or against the Company under either such statute, and either (x) the
     trust funds will no longer remain the property of the Company (and
     therefore, will not be subject to the effect of any applicable bankruptcy,
     insolvency, reorganization or similar laws affecting creditors' rights
     generally) or (y) if a court were to rule under any such law in any case or
     proceeding that the trust funds remained property of the Company, (I)
     assuming such trust funds remained in the possession of the Trustee prior
     to such court ruling to the extent not paid to Holders of such Series, the
     Trustee will hold, for the benefit of such Holders, a valid and perfected
     security interest in such trust funds that is not avoidable in bankruptcy
     or otherwise except for the effect of Section 552(b) of the United States
     Bankruptcy Code on interest on the trust funds accruing after the
     commencement of a case under such statute and (II) such Holders will be
     entitled to receive adequate protection of their interests in such trust
     funds if such trust funds are used in such case or proceeding; and

          (v) the Company has delivered to the Trustee an Officers' Certificate
     and an Opinion of Counsel, in each case stating that all conditions
     precedent provided for herein relating to the defeasance contemplated by
     this Section 7.3 have been complied with.

     Notwithstanding the foregoing clause (i), prior to the end of the 123-day
period referred to in clause (iv)(B)(2) above, none of the Company's obligations
under this Indenture with respect to such Series shall be discharged. Subsequent
to the end of such 123-day period with respect to this Section 7.3, the
Company's obligations in Sections 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.12, 3.1,
3.2, 6.7, 6.8, 7.6 and 7.7 shall survive with respect to such Series until the
Series is no longer outstanding. Thereafter, only the Company's obligations in
Sections 6.7, 7.6 and 7.7 shall survive with respect to such Series. If and when
a ruling from the Internal Revenue Service or Opinion of Counsel referred to in
clause (iv)(A) above is able to be provided specifically without regard to, and
not in reliance upon, the continuance of the Company's obligations under Section
3.1, then the Company's obligations under such Section 3.1 with respect to such
Series shall cease upon delivery to the
                                       36
<PAGE>   37

Trustee of such ruling or Opinion of Counsel and compliance with the other
conditions precedent provided for herein relating to the defeasance contemplated
by this Section 7.3.

     After any such irrevocable deposit and the fulfillment of the other
requirements of this Section 7.3, the Trustee upon request shall acknowledge in
writing the discharge of the Company's obligations under the Securities of such
Series and this Indenture with respect to such Series except for those surviving
obligations in the immediately preceding paragraph.

     Before or after a deposit pursuant to this Section, the Company may make
arrangements satisfactory to the Trustee for the redemption of Securities at a
future date in accordance with Article IX.

SECTION 7.4  Defeasance of Certain Obligations.

     With respect to a Series of Securities, the Company may omit to comply with
any term, provision or condition set forth in Sections 3.3, 3.4 and 3.7 or any
Covenant established with respect to such Series pursuant to Section 2.1(9), and
clause (c) of Section 5.1 with respect to Sections 3.3, 3.4 and 3.7 or any such
Covenant, and clause (d) of Section 5.1 shall be deemed not to be an Event of
Default, in each case with respect to the outstanding Securities of such Series,
if:

          (i) with reference to this Section 7.4, the Company has irrevocably
     deposited or caused to be irrevocably deposited with the Trustee or Paying
     Agent (other than the Company or a Subsidiary or Affiliate of the Company)
     and conveyed all right, title and interest for the benefit of the Holders
     of such Series, under the terms of an irrevocable trust agreement in form
     satisfactory to the Trustee as trust funds in trust, specifically pledged
     as security for, and dedicated solely to, the benefit of the Holders of
     such Series, in and to, (A) money in an amount, (B) U.S. Government
     Obligations that, through the payment of interest and principal in respect
     thereof in accordance with their terms, will provide, not later than one
     Business Day before the due date of any payment referred to in this clause
     (i), money in an amount or (C) a combination thereof in an amount,
     sufficient, in the opinion of a nationally recognized firm of independent
     public accountants expressed in a written certification thereof delivered
     to the Trustee, to pay and discharge, without consideration of the
     reinvestment of such interest and after payment of all federal, state and
     local taxes or other fees, charges and assessments in respect thereof
     payable by the Trustee or Paying Agent, the principal of, premium, if any,
     and interest on the outstanding Securities of such Series when due;
     provided, however, that the Trustee or Paying Agent shall have been
     irrevocably instructed to apply such money or the proceeds of such U.S.
     Government Obligations to the payment of such principal and interest with
     respect to such Series;

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

          (iii) no Default with respect to such Series shall have occurred and
     be continuing on the date of such deposit;

          (iv) the Company has delivered to the Trustee an Opinion of Counsel
     who is not employed by the Company to the effect that (A) the creation of
     the defeasance trust does not violate the Investment Company Act of 1940,
     (B) the Holders of such Series have a valid first-priority security
     interest in the trust funds, (C) such Holders will not recognize income,
     gain or loss for federal income tax purposes as a result of such deposit
     and defeasance of certain obligations and will be subject to federal income
     tax on the same amount and in the same manner and at the same times as
     would have been the case if such deposit and defeasance had not occurred
     and (D) after the passage of 183 days following the deposit (except, with
     respect to any trust funds
                                       37
<PAGE>   38

     for the account of any Holder who may be deemed to be an "insider" for
     purposes of the United States Bankruptcy Code, after one year following the
     deposit), the trust funds will not be subject to the effect of Section 547
     of the United States Bankruptcy Code or Section 15 of the New York Debtor
     and Creditor Law in a case commenced by or against the Company under either
     such statute, and either (1) the trust funds will no longer remain the
     property of the Company (and therefore, will not be subject to the effect
     of any applicable bankruptcy, insolvency, reorganization or similar laws
     affecting creditors' rights generally) or (2) if a court were to rule under
     any such law in any case or proceeding that the trust funds remained
     property of the Company, (x) assuming such trust funds remained in the
     possession of the Trustee prior to such court ruling to the extent not paid
     to such Holders, the Trustee will hold, for the benefit of such Holders, a
     valid and perfected security interest in such trust funds that is not
     avoidable in bankruptcy or otherwise except for the effect of Section
     552(b) of the United States Bankruptcy Code on interest on the trust funds
     accruing after the commencement of a case under such statute and (y) such
     Holders will be entitled to receive adequate protection of their interests
     in such trust funds if such trust funds are used in such case or
     proceeding; and

          (v) the Company has delivered to the Trustee an Officers' Certificate
     and an Opinion of Counsel, in each case stating that all conditions
     precedent provided for herein relating to the defeasance contemplated by
     this Section 7.4 have been complied with.

     Before or after a deposit pursuant to this Section, the Company may make
arrangements satisfactory to the Trustee for the redemption of Securities at a
future date in accordance with Article IX.

SECTION 7.5  Application of Trust Money.

     Subject to Section 7.7 of this Indenture, the Trustee or Paying Agent shall
hold in trust money or U.S. Government Obligations deposited with it pursuant to
Section 7.1, 7.2, 7.3 or 7.4 of this Indenture, as the case may be, and shall
apply the deposited money and the money from U.S. Government Obligations in
accordance with this Indenture to the payment of principal of and interest on
the Securities of the relevant Series. The Trustee shall be under no obligation
to invest such money or U.S. Government Obligations and in no event shall the
Trustee have any liability for, or in respect of, any such investment made.

SECTION 7.6  Repayment to Company.

     Subject to Sections 6.7, 7.1, 7.2, 7.3 and 7.4 of this Indenture, the
Trustee and the Paying Agent shall promptly pay to the Company upon written
request any excess money or U.S. Government Obligations held by them at any time
pursuant to this Article, which in the opinion of a nationally recognized firm
of independent public accountants expressed in a written certification thereof
delivered to the Trustee (which delivery shall only be required if U.S.
Government Obligations have been so provided), are in excess of the amount
thereof which would then be required to be deposited to effect an equivalent
discharge or defeasance in accordance with this Article VII, and thereupon shall
be relieved from all liability with respect to such money. The Trustee and the
Paying Agent shall pay to the Company upon written request any money held by
them for the payment of principal or interest of any Series that remains
unclaimed for two years; provided, however, that the Company shall if requested
by the Trustee or the Paying Agent, give the Trustee or such Paying Agent
indemnification reasonably satisfactory to it against any and all liability
which may be incurred by it by reason of such payment. After payment to the
Company, Holders entitled to such money must look to the Company for payment as
general creditors unless an applicable law designates another person, and all
liability of the Trustee and such Paying Agent with respect to such money shall
cease.

                                       38
<PAGE>   39

SECTION 7.7  Reinstatement.

     If the Trustee or Paying Agent is unable to apply any money or U.S.
Government Obligations in accordance with Section 7.1, 7.2, 7.3 or 7.4 of this
Indenture, as the case may be, 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 obligations
under this Indenture and the Securities of the applicable Series shall be
revived and reinstated as though no deposit had occurred pursuant to Section
7.1, 7.2, 7.3 or 7.4 of this Indenture, as the case may be, until such time as
the Trustee or Paying Agent is permitted to apply all such money or U.S.
Government Obligations in accordance with Section 7.1, 7.2, 7.3 or 7.4 of this
Indenture, as the case may be; provided, however, that, if the Company has made
any payment of principal of or interest on any Series of Securities because of
the reinstatement of its obligations, the Company shall be subrogated to the
rights of the Holders of such Series to receive such payment from the money or
U.S. Government Obligations held by the Trustee or Paying Agent.

SECTION 7.8 Deposited Money and U.S. Government Obligations to be Held in Trust:
            Miscellaneous Provisions.

     The Company shall pay and indemnify the Trustee against any tax, fee or
other charge imposed on or assessed against the U.S. Government Obligations
deposited 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 outstanding Securities.

                                  ARTICLE VIII

                           AMENDMENTS AND SUPPLEMENTS

SECTION 8.1  Without Consent of Holders.

     The Company, when authorized by a Board Resolution and the Trustee may
amend this Indenture or a Series of Securities or enter into an indenture or
indentures supplemental hereto (which shall conform to the provisions of the
Trust Indenture Act as then in effect) without notice to or the consent of any
Securityholder for one or more of the following purposes:

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

          (b) to comply with Article IV;

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

          (d) to add additional guarantees with respect to such Series or to
     secure such Series;

          (e) to add to the covenants of the Company for the benefit of the
     Holders of such Series or to surrender any right or power herein conferred
     upon the Company;

          (f) to comply with the requirements of the SEC in connection with
     qualification of the Indenture under the TIA;

          (g) to make any change that does not adversely affect the rights of
     any Securityholder of such Series; or

          (h) to provide for the issuance of Securities with terms not currently
     contemplated by Section 2.1.
                                       39
<PAGE>   40

     After an amendment or supplement pursuant this Section becomes effective,
the Company shall mail to Securityholders a notice briefly describing such
amendment or supplement. The failure to give such notice to all Securityholders,
or any defect therein, shall not impair or affect the validity of an amendment
or supplement under this Section.

SECTION 8.2  With Consent of Holders.

     The Company and the Trustee may amend or supplement this Indenture or the
Securities of a Series with the written consent of the Holders of a majority in
principal amount of the Securities of each Series affected by such amendment or
supplement. However, without the consent of each Securityholder affected, an
amendment or supplement under this Section may not:

          (a) reduce the amount of Securities the Holders of which must consent
     to an amendment or supplement or waiver pursuant to Section 3.9;

          (b) reduce the rate of or change the time for payment of interest on
     any Security;

          (c) reduce the principal of or change the Stated Maturity of any
     Security;

          (d) modify any redemption or repurchase right to the detriment of a
     Holder;

          (e) make any Security payable in currency or consideration other than
     that stated in the Security;

          (f) make any change in Section 5.4, Section 5.7 or this second
     sentence of this Section 8.2.

     An amendment or supplement which changes or eliminates any covenant or
other provision of this Indenture which has expressly been included solely for
the benefit of one or more particular Series of Securities, or which modifies
the rights of the Holders of Securities of such Series with respect to such
covenant or other provision, shall be deemed not to affect the rights under this
Indenture of the Holders of Securities of any other Series.

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

     After an amendment or supplement under this Section becomes effective, the
Company shall mail to Securityholders a notice briefly describing such amendment
or supplement. The failure to give such notice to all Securityholders, or any
defect therein, shall not impair or affect the validity of an amendment or
supplement under this Section.

SECTION 8.3  Compliance with Trust Indenture Act.

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

SECTION 8.4  Revocation and Effect of Consents.

     Until an amendment or supplement under this Article or a waiver under
Section 3.8 becomes effective, a consent to it by a Holder of any Security is a
continuing consent by the Holder and every subsequent Holder of Securities of
that Series or portion thereof that evidences the same debt as the consenting
Holder's Security, even if notation of the consent is not made on any Security.
However, any such Holder or subsequent Holder may revoke the consent as to his
Security or portion of a Security if the Trustee receives the notice of
revocation before the date the amendment, supplement or waiver becomes
effective.

                                       40
<PAGE>   41

     After an amendment or supplement becomes effective, it shall bind every
Securityholder of the affected Series.

SECTION 8.5  Notation on or Exchange of Securities.

     If an amendment changes the terms of a Security, the Trustee may require
the Holders of the Security to deliver it to the Trustee. The Trustee may place
an appropriate notation on the Securities of such Series regarding the changed
terms and return it to the Holders. Alternatively, if the Company or the Trustee
so determines, the Company in exchange for the Securities of such Series shall
issue and the Trustee shall authenticate new Securities of such Series that
reflect the changed terms. Failure to make the appropriate notation or to issue
a new Securities of such Series shall not affect the validity of such amendment.

SECTION 8.6  Trustee To Sign Amendments.

     The Trustee shall sign any supplemental indenture which sets forth an
amendment or supplement authorized pursuant to this Article if the amendment or
supplement does not adversely affect the rights, duties, liabilities or
immunities of the Trustee under this Indenture or otherwise. If it does, the
Trustee may but need not sign it. In signing such supplemental indenture the
Trustee shall be entitled to receive, and (subject to Section 6.1) shall be
fully protected in relying upon, an Officers' Certificate and an Opinion of
Counsel stating that such supplemental indenture is authorized or permitted by
this Indenture and, with respect to an amendment or supplement pursuant to
Section 8.2, evidence of the consents of Holders required in connection
therewith.

SECTION 8.7  Fixing of Record Dates.

     The Company may, but shall not be obligated to, fix a record date for the
purpose of determining the Holders entitled to take any action under this
Indenture by vote or consent. Except as provided herein, such record date shall
be the later of 30 days prior to the first solicitation of such consent or vote
or the date of the most recent list of Securityholders furnished to the Trustee
pursuant to Section 2.6 prior to such solicitation. If a record date is fixed,
those Persons who were Securityholders at such record date (or their duly
designated proxies), and only those Persons, shall be entitled to take such
action by vote or consent or to revoke any vote or consent previously given,
whether or not such Persons continue to be Holders after such record date;
provided, however, that unless such vote or consent is obtained from the Holders
(or their duly designated proxies) of the requisite principal amount of
outstanding Securities prior to the date which is the 120th day after such
record date, any such vote or consent previously given shall automatically and
without further action by any Holder be canceled and of no further effect.

                                   ARTICLE IX

                                   REDEMPTION

SECTION 9.1  Applicability of Article.

     Securities of any Series which are redeemable before their Stated Maturity
shall be redeemable in accordance with their terms and (except as otherwise
specified as contemplated by Section 2.1) in accordance with this Article.

SECTION 9.2  Election to Redeem; Notice to Trustee.

     The election of the Company to redeem Securities of any Series shall be
evidenced by a resolution of the Board of Directors. In case of any redemption
at the election of the Company, the
                                       41
<PAGE>   42

Company shall, at least 60 days prior to the Redemption Date fixed by the
Company (unless a shorter notice shall be satisfactory to the Trustee), notify
the Trustee of such Redemption Date and of the principal amount of Securities of
such Series to be redeemed. In the case of any redemption of such Securities (i)
prior to the expiration of any restriction on such redemption provided in the
terms of such Securities or elsewhere in this Indenture or (ii) that is subject
to compliance with any conditions provided for in the terms of such Securities
or elsewhere in this Indenture, the Company shall furnish the Trustee with an
Officers' Certificate evidencing compliance with such restriction or conditions.

SECTION 9.3  Selection by Trustee of Securities to be Redeemed.

     If less than all the Securities of the Series are to be redeemed, the
particular Securities to be redeemed shall be selected not more than 60 days
prior to the Redemption Date by the Trustee, from the outstanding Securities of
such Series not previously called for redemption, by such method as the Trustee
shall deem fair and appropriate and which may provide for the selection for
redemption of portions (equal to authorized denominations for Securities of that
Series) of the principal amount of Securities of such Series.

     The Trustee shall promptly notify the Company in writing of the Securities
selected for redemption and, in the case of any Securities selected for partial
redemption, the principal amount thereof to be redeemed.

     For all purposes of this Indenture, unless the context otherwise requires,
all provisions relating to the redemption of Securities of any Series shall
relate, in the case of any Securities redeemed or to be redeemed only in part,
to the portion of the principal amount of such Securities which has been or is
to be redeemed.

SECTION 9.4  Notice of Redemption.

     Notice of redemption shall be given by first-class mail, postage prepaid,
mailed not less than 30 nor more than 60 days prior to the Redemption Date, to
each Holder of Securities to be redeemed, at such Holder's registered address.

     All notices of redemption shall identify the Securities to be redeemed
(including CUSIP numbers) and shall state:

          (1) the Redemption Date,

          (2) the Redemption Price,

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

          (4) that on the Redemption Date, the Redemption Price will become due
     and payable upon each such Security to be redeemed and, if applicable, that
     interest thereon will cease to accrue on and after said date,

          (5) the place or places where such Securities are to be surrendered
     for payment of the Redemption Price, and

          (6) that the redemption is for a sinking fund, if such is the case.

     Notice of redemption of Securities of any Series to be redeemed at the
election of the Company shall be given by the Company or, at the Company's
request, by the Trustee in the name and at the expense of the Company. The
notice if mailed in the manner herein provided shall be conclusively presumed to
have been duly given, whether or not the Holder receives such notice. In any
case, a
                                       42
<PAGE>   43

failure to give such notice by mail or any defect in the notice to the Holder of
any Security designated for redemption as a whole or in part shall not affect
the validity of the proceedings for the redemption of any other Security.

SECTION 9.5  Deposit of Redemption Price.

     Notice of redemption having been given as aforesaid, the Securities so to
be redeemed shall, on the Redemption Date, become due and payable at the
Redemption Price therein specified, and from and after such date (unless the
Company shall default in the payment of the Redemption Price and accrued
interest) such Securities shall cease to bear interest. Upon surrender of any
such Security for redemption in accordance with said notice, such Security shall
be paid by the Company at the Redemption Price, together with accrued interest
to the Redemption Date; provided, however, that installments of interest whose
Stated Maturity is on or prior to the Redemption Date shall be payable to the
Holders of such Securities registered as such at the close of business on the
relevant record dates according to their terms.

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

SECTION 9.6  Securities Redeemed in Part.

     Any Security which is to be redeemed only in part shall be surrendered at
the office of the Paying Agent (with, if the Company or the Trustee for such
Security so requires, due endorsement by, or a written instrument of transfer in
form satisfactory to the Company and the Trustee duly executed by, the Holder
thereof or his attorney duly authorized in writing), and the Company shall
execute, and the Trustee shall authenticate and deliver to the Holder of such
Security without service charge, a new Security or Securities of the same
Series, of any authorized denomination as requested by such Holder, in aggregate
principal amount equal to and in exchange for the unredeemed portion of the
principal of the Security so surrendered.

                                   ARTICLE X

                                 MISCELLANEOUS

SECTION 10.1  Trust Indenture Act Controls.

     If any provision of this Indenture limits, qualifies or conflicts with the
duties imposed by any of TIA Sections 310 to 317, inclusive, through operation
of TIA Section 318(c), such imposed duties shall control.

SECTION 10.2  Notices.

     Any notice or communication shall be in writing and delivered in person, or
mailed by first-class mail (certified, return receipt requested), addressed as
follows:

         if to the Company:

         Calpine Corporation
         50 West San Fernando Street
         San Jose, California 95113
         Attention: Corporate Secretary

                                       43
<PAGE>   44

         if to the Trustee:

         Wilmington Trust Company
         Rodney Square North
         1100 North Market Street
         Wilmington, DE 19890
         Attention: Corporate Trust Trustee Administration

     The Company or the Trustee by notice to the others may designate additional
or different addresses for subsequent notices or communications. Any notice to
the Trustee under this Indenture shall be deemed given only when received by the
Trustee at the address specified in this Section 10.2.

     Any notice or communication to a Securityholder shall be mailed by
first-class mail to the Securityholder's address shown on the register kept by
the Registrar. Failure to mail a notice or communication to a Securityholder or
any defect in it shall not affect its sufficiency with respect to other
Securityholders.

     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 Securityholders, it shall
mail a copy to the Trustee and each Agent at the same time.

SECTION 10.3  Communication by Holders with Other Holders.

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

SECTION 10.4  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, if requested by the Trustee,
furnish to the Trustee:

          (a) an Officers' Certificate in form reasonably satisfactory to the
     Trustee stating that, in the opinion of the signers, all conditions
     precedent (including any covenants compliance with which constitutes a
     condition precedent), if any, provided for in this Indenture relating to
     the proposed action have been complied with; and

          (b) an Opinion of Counsel in form reasonably satisfactory to the
     Trustee stating that, in the opinion of such counsel (which may rely upon
     an Officers' Certificate as to factual matters), all such conditions
     precedent have been complied with.

SECTION 10.5  Statements Required in Certificate or Opinion.

     Each Officers' Certificate or Opinion of Counsel with respect to compliance
with a condition or covenant provided for in this Indenture other than
certificates provided pursuant to Section 3.5 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;

                                       44
<PAGE>   45

          (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 complied with; and

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

SECTION 10.6  Rules by Trustee and Agents.

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

SECTION 10.7  Legal Holidays.

     A "Legal Holiday" is a Saturday, a Sunday or a day on which banking
institutions are not required to be open in the State of New York or the
State(s) in which the offices of the Trustee or the Paying Agent are located. If
a payment date is a Legal Holiday, 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. If a regular record date is a Legal Holiday, the regular
record date shall not be affected.

SECTION 10.8  Successors; No Recourse Against Others.

     (a) All agreements of the Company in this Indenture and the Securities
shall bind its successor. All agreements of the Trustee in this Indenture shall
bind its successor.

     (b) All liability of the Company described in the Securities insofar as it
relates to any director, officer, employee or stockholder, as such, of the
Company is waived and released by each Securityholder.

SECTION 10.9  Duplicate Originals.

     The parties may sign any number of copies of this Indenture. One signed
copy is enough to prove this Indenture.

SECTION 10.10  Other Provisions.

     The first certificate pursuant to Section 3.5 shall be for the fiscal year
ending on December 31, 2000.

     The reporting date for Section 6.6 is April 15 of each year. The first
reporting date is April 15, 2001.

SECTION 10.11  Governing Law.

     The laws of the State of New York govern this Indenture and the Securities,
without regard to the conflicts of laws rules thereof.

                                       45
<PAGE>   46

                                   SIGNATURES

                                          CALPINE CORPORATION

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

                                          WILMINGTON TRUST COMPANY,
                                          as Trustee

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

Dated:           , 2000

                                       46
<PAGE>   47

                                                                       EXHIBIT A

                           (Form of Face of Security)

     [THIS SECURITY IS ISSUED IN GLOBAL FORM AND REGISTERED IN THE NAME OF THE
DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC") OR A NOMINEE THEREOF.
UNLESS THIS SECURITY IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF DTC, TO THE
COMPANY (AS DEFINED BELOW) OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE
OR PAYMENT, AND ANY SECURITY ISSUED IS REGISTERED IN THE NAME OF CEDE & CO., OR
SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY
PAYMENT IS MADE TO CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR
VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED
OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

     UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR SECURITIES IN
DEFINITIVE REGISTERED FORM IN ACCORDANCE WITH THE TERMS HEREOF AND OF THE
INDENTURE (AS DEFINED BELOW), THIS SECURITY MAY NOT BE TRANSFERRED EXCEPT AS A
WHOLE BY DTC TO A NOMINEE OF DTC OR BY A NOMINEE OF DTC TO DTC OR ANOTHER
NOMINEE OF DTC OR BY DTC OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITORY OR A
NOMINEE OF SUCH SUCCESSOR DEPOSITORY.]*

<PAGE>   48

                               CALPINE CORPORATION
                                % SENIOR NOTE DUE


No.____                                                           $_____________
                                                                   CUSIP:
                                                                   ISIN:

     Calpine Corporation, a Delaware corporation, promises to pay to [Cede &
Co.]*, or registered assigns, the principal sum of ____________ Dollars on
_______________.

                Interest Payment Dates: __________ and __________
                     Record Dates: __________ and __________

     Additional provisions of this Security are set forth on the reverse hereof.

     IN WITNESS WHEREOF, the Company has caused this Security to be signed
manually or by facsimile by its duly authorized officers.

Date: _______________

                                        CALPINE CORPORATION

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


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

TRUSTEE'S CERTIFICATE
OF AUTHENTICATION:

Wilmington Trust Company, as Trustee,
certifies that this is one of the
Securities referred to in the Indenture.

By:                                      Dated:
   -----------------------------------         ---------------------------------
           Authorized Officer


*Insert in Global Security only.


                                       2

<PAGE>   49

                          (Form of Reverse of Security)

                               CALPINE CORPORATION
                           ___% SENIOR NOTE DUE _____

     (1)  Interest. Calpine Corporation, a Delaware corporation (such
corporation, and its successors and assigns under the Indenture referred to
below, being herein called the "Company"), promises to pay interest on the
principal amount of this Security at ___% per annum shown above. The Company
will pay interest semiannually on __________ and __________ of each year.
Interest on the Securities of this Series will accrue from the most recent date
to which interest has been paid or duly provided for or, if no interest has been
paid or duly provided for, from ________________. Interest will be computed [on
the basis of a 360-day year consisting of twelve 30-day months] [as set forth in
the Directors' Certificate or supplementary indenture delivered pursuant to
Section 2.1.


     (2)  Method of Payment. The Company will pay interest on the Securities of
this Series (except Defaulted Interest) to the persons who are registered
Holders of Securities of this Series at the close of business on the record date
next preceding the interest payment date even though such Securities are
canceled after the record date and on or before the interest payment date.
Holders must surrender Securities to a Paying Agent to collect principal
payments. The Company will pay principal and interest in money of the United
States that at the time of payment is legal tender for payment of public and
private debts. However, the Company may pay principal and interest by check
payable in such money. It may mail an interest check to a Holder's registered
address.

     (3)  Paying Agent, Registrar. Initially, The Wilmington Trust Company, a
Delaware banking corporation (the "Trustee"), will act as Paying Agent and
Registrar. The Company may change any Paying Agent, Registrar or co-registrar
without notice. The Company may act as Paying Agent, Registrar or co-registrar.

     (4)  Indenture. The Company issued the Securities of this Series under an
Indenture dated as of _______________ (the "Indenture") between the Company and
the Trustee. The Securities are unsecured general obligations of the Company and
may be issued in an unlimited principal amount. The terms of the Securities
include those stated in the Indenture and those made part of the Indenture by
reference to the Trust Indenture Act of 1939 (15 U.S. Code Sections
77aaa-77bbbb) (the "TIA"). Capitalized terms used herein but not defined herein
are used as defined in the Indenture. The Securities are subject to all such
terms, and Securityholders are referred to the Indenture and the TIA for a
statement of such terms.

     (5)  Redemption. Securities of any Series which are redeemable before their
Stated Maturity shall be redeemable in accordance with their terms and (except
as otherwise specified as contemplated by Section 2.1 of the Indenture) in
accordance with Article IX of the Indenture. The election of the Company to
redeem Securities of any Series shall be evidenced by a Board Resolution. In
case of any redemption at the election of the Company, the Company shall, at
least 60 days prior to the Redemption Date fixed by the Company (unless a
shorter notice shall be satisfactory to the Trustee), notify the Trustee of such
Redemption Date and of the principal amount of Securities of such Series to be
redeemed. In the case of any redemption of such Securities (i) prior to the
expiration of any restriction on such redemption provided in the terms of such
Securities or elsewhere in the Indenture or (ii) that is subject to compliance
with any conditions provided for in the terms of such Securities or elsewhere in
the Indenture, the Company shall furnish the Trustee with an Officers'
Certificate evidencing compliance with such restriction or conditions. If less
than all the Securities of the Series are to be redeemed, the particular
Securities to be redeemed shall be selected not more than 60 days prior to the
Redemption Date by the Trustee, from the outstanding Securities of such Series
not previously called for redemption, by such method as the Trustee shall deem
fair and appropriate and which may provide for the selection for redemption of
portions (equal to authorized denominations for Securities of that Series) of
the principal amount of Securities of such Series. The Trustee shall promptly
notify the Company in writing of the Securities selected for redemption and, in
the case of any Securities selected for partial redemption, the principal amount
thereof to be redeemed. For all purposes of this Indenture, unless the context
otherwise requires, all provisions relating to the redemption of Securities of
any Series shall relate, in the case of any Securities redeemed or to be
redeemed only in part, to the portion of the principal amount of such Securities
which has been or is to be redeemed. Notice of redemption shall be given by
first-class mail, postage prepaid, mailed not less than 30 nor more than 60 days
prior to the Redemption Date, to each Holder of Securities to be redeemed, at
such Holder's registered address.

     All notices of redemption shall identify the Securities to be redeemed
(including CUSIP numbers) and shall state:

     (1)  the Redemption Date,

     (2)  the Redemption Price,

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

     (4)  that on the Redemption Date, the Redemption Price will become due and
payable upon each such Security to be redeemed and, if applicable, that
interest thereon will cease to accrue on and after said date,

     (5)  the place or places where such Securities are to be surrendered for
payment of the Redemption Price, and

     (6)  that the redemption is for a sinking fund, if such is the case.

     Notice of redemption of Securities of any Series to be redeemed at the
election of the Company shall be given by the Company, or, at the Company's
request, by the Trustee in the name and at the expense of the Company. The
notice if mailed in the manner herein provided shall be conclusively presumed to
have been duly given, whether or not the Holder receives such notice. In any
case, a failure to give such notice by mail or any defect in the notice to the
Holder of any Security designated for redemption as a whole or in part shall not
affect the validity of the proceedings for the redemption of any other Security.
Notice of redemption having been given as aforesaid, the Securities so to be
redeemed shall, on the Redemption Date, become due and payable at the Redemption
Price therein specified, and from and after such date (unless the Company shall
default in the payment of the Redemption Price and accrued interest) such
Securities shall cease to bear interest. Upon surrender of any such Security for
redemption in accordance with said notice, such Security shall be paid by the
Company at the Redemption Price, together with accrued interest to the
Redemption Date; provided, however, that installments of interest whose Stated
Maturity is on or prior to the Redemption Date shall be payable to the Holders
of such Securities registered as such at the close of business on the relevant
record dates according to their terms. If any Security called for redemption
shall not be so paid upon surrender thereof for redemption, the principal shall,
until paid, bear interest from the Redemption Date at the rate prescribed
therefor in the Security.

     Any Security which is to be redeemed only in part shall be surrendered at
the office of the Paying Agent (with, if the Company or the Trustee for such
Security so requires, due endorsement by, or a written instrument of transfer in
form satisfactory to the Company and the Trustee duly executed by, the Holder
thereof or his attorney duly authorized in writing), and the Company shall
execute, and the Trustee shall authenticate and deliver to the Holder of such
Security without service charge, a new Security or Securities of the same
Series, of any authorized denomination as requested by such Holder, in aggregate
principal amount equal to and in exchange for the unredeemed portion of the
principal of the Security so surrendered.

     (6)  Denominations; Transfer; Exchange. The Securities of this Series are
in registered form without coupons in denominations of $1,000 and any integral
multiple thereof [or as otherwise set forth in the Security]. The transfer of
Securities may be registered and Securities may be exchanged as provided in the
Indenture. The Registrar may require a Holder, among other things, to furnish
appropriate endorsements and transfer documents and to pay any taxes and fees
required by law or permitted by the Indenture. The Company shall not be required
(A) to issue, register the transfer of or exchange any Securities of a Series
during a period beginning at the opening of business 15 days before the day of
the mailing of a notice of redemption of any such Securities selected for
redemption under Section 9.3 and ending at the close of business on the day of
such mailing or (B) to register the transfer of or exchange any Security so
selected for redemption in whole or in part, except the unredeemed portion of
any Security being redeemed in part.


                                       3

<PAGE>   50

     (7)  Defeasance. Subject to certain conditions and unless otherwise
provided in the terms of the Securities of this Series, the Company at any time
may terminate some or all of its obligations under the Securities and the
Indenture if the Company deposits with the Trustee money and/or U.S. Government
Obligations for the payment of principal and interest on the Securities to
maturity.

     (8)  Persons Deemed Owners. The registered Holder of a Security may be
treated as its owner for all purposes, except that interest (other than
Defaulted Interest) will be paid to the person that was the registered Holder on
the relevant record date for such payment of interest.

     (9)  Amendments and Waivers. Subject to certain exceptions, (i) the
Indenture or the Securities may be amended or supplemented with the consent of
the Holders of a majority in principal amount of the Securities of each Series
affected; and (ii) any existing default with respect to the Securities of this
Series may be waived with the consent of the Holders of a majority in principal
amount of the Securities of such Series. Without the consent of any
Securityholder, the Indenture or the Securities may be amended or supplemented
to cure any ambiguity, omission, defect or inconsistency, to provide for
assumption of Company obligations to Securityholders or to provide for
uncertificated Securities in addition to or in place of certificated Securities,
to provide for guarantees with respect to, or security for, the Securities, or
to comply with the TIA or to add additional covenants or surrender Company
rights, or to make any change that does not adversely affect the rights of any
Securityholder.

     (10) Remedies. If an Event of Default with respect to the Securities of
this Series occurs and is continuing, the Trustee or Holders of at least 25% in
principal amount of the Securities may declare all the Securities to be due and
payable immediately. Securityholders may not enforce the Indenture or the
Securities of this Series except as provided in the Indenture. The Trustee may
require an indemnity before it enforces the Indenture or the Securities. Subject
to certain limitations, Holders of a majority in principal amount of the
Securities of a Series may direct the Trustee in its exercise of any trust or
power with respect to such Series. The Trustee may withhold from Securityholders
notice of any continuing default (except a Default in payment of principal or
interest) if it determines that withholding notice is in their interests. The
Company must furnish an annual compliance certificate to the Trustee.

     (11) Trustee Dealings with Company. Subject to the provisions of the TIA,
the Trustee under the Indenture, in its individual or any other capacity, may
make loans to, accept deposits from, and perform services for the Company or its
Affiliates, and may otherwise deal with the Company or its Affiliates, as if it
were not Trustee. The Trustee will initially be Wilmington Trust Company.

     (12) No Recourse Against Others. A director, officer, employee or
stockholder, as such, of the Company shall not have any liability for any
obligations of the Company under the Securities or the Indenture or for any
claim based on, in respect of or by reason of such obligations or their
creation. Each Securityholder by accepting a Security waives and releases all
such liability. The waiver and release are part of the consideration for the
issue of the Securities.

     (13) Authentication. This Security shall not be valid until authenticated
by the manual signature of an authorized officer of the Trustee or an
authenticating agent.

     (14) Abbreviations. Customary abbreviations may be used in the name of a
Securityholder 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).


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<PAGE>   51

     Pursuant to a recommendation promulgated by the Committee on Uniform
Security Identification Procedures the Company has caused CUSIP numbers to be
printed on the Securities. No representation is made as to the accuracy of such
numbers as printed on the Securities and reliance may be placed only on the
other identification numbers placed thereon.

     THE COMPANY WILL FURNISH TO ANY SECURITYHOLDER UPON WRITTEN REQUEST AND
WITHOUT CHARGE A COPY OF THE INDENTURE, WHICH HAS IN IT THE TEXT OF THIS
SECURITY IN TWELVE-POINT TYPE. REQUESTS MAY BE MADE TO: SECRETARY, CALPINE
CORPORATION, 50 WEST SAN FERNANDO STREET, SAN JOSE, CALIFORNIA 95113.


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<PAGE>   52

                                 ASSIGNMENT FORM

To assign this Security, fill in the form below:

     I or we assign and transfer this Security to

                  (Insert assignee's soc. sec or tax I.D. no.)


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

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

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              (Print or type assignee's name, address and zip code)

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

Dated:                                  Signed:
      ----------------                         ---------------------------------
                                        (Sign exactly as your name appears
                                        on the other side of this Security)

Signature Guarantee:
                    ------------------------------------------------------------

Signatures must be guaranteed by an "eligible guarantor institution" meeting the
requirements of the Registrar, which requirements include membership or
participation in the Security Transfer Agent Medallion Program ("STAMP") or such
other "signature guarantee program" as may be determined by the Registrar in
addition to, or in substitution for, STAMP, all in accordance with the
Securities Exchange Act of 1934, as amended.


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