Document:

<PAGE>   1
                                                                    EXHIBIT 10.3

                      Enviro Industrial Technologies, Inc.
                              119 West 23rd Street
                                    Suite 508
                            New York, New York 10011

                                                  June 5, 2000

Hedman Resources Limited
106 Fielding Road
Lively, Ontario P3Y 1L5

Attention:  Claude Taillefer
            CEO and President

                 RE: ACQUISITION OF HEDMAN RESOURCES LIMITED

Gentlemen:

         This letter expresses our understanding with respect to the acquisition
(the "Acquisition") of up to all of, but no less than eighty (80%) percent of
the issued and outstanding shares of common stock of Hedman Resources Limited
("Hedman")by Enviro Industrial Technologies, Inc., a Delaware Corporation
("Enviro") in exchange for shares of common stock of Enviro on a one for one
basis on the date of closing. The common shares of Hedman are hereinafter
referred to as the "Shares". After the acquisition, Hedman will become a
subsidiary of Enviro.

         It is hereby represented that Hedman is authorized to issue
an unlimited number of Shares of which, 28,073,035 Shares are issued and
outstanding. It is further represented that Hedman has outstanding warrants to
purchase 13,913,653 Shares (the "Warrants"). Anything to the contrary herein
notwithstanding, Hedman shall, as a condition of closing, cause to be
implemented, a one (1) share for (2) share reverse stock split of its Shares,
including the shares underlying the Warrants (the "Reverse Split").

         Enviro represents it is authorized to issue 80,000,000 shares of common
stock, par value $.001 per share and 20,000,000 shares of preferred stock, par
value $.001 per share. At the time of closing, Enviro will have no more than
13,750,000 shares of common stock outstanding.
<PAGE>   2
         In connection with the Acquisition we have the following
understandings:

         (1) Reorganization. At the closing of this transaction, as set forth in
Section 7 hereof, Enviro will acquire the Shares in exchange, on a one for one
basis, for up to 20,944,743 shares of common stock of Enviro (the "Acquisition
Shares"). In the event less than all of the Shares are exchanged for the Enviro
shares, the number of Acquisition Shares will be reduced pro rata with the
actual percentage of Shares acquired by Enviro.

         (2) Registered Shares. Enviro will file an F-4 Registration Statement
(the "Registration Statement") with the United States Securities and Exchange
Commission ("SEC") so that the Acquisition Shares will be registered under the
Securities Act of 1933 (the "Act") prior to or on the closing, or if not
permitted by law prior to the closing, then immediately after the closing.
Enviro will utilize its best efforts to have the Registration Statement declared
effective by the SEC no later than 120 days after the closing.

         (3) Conditions. It is the intention of Enviro and Hedman that this
letter be binding on Enviro and Hedman subject to the following: (i)the exchange
of a minimum of 80% of the outstanding Shares of Hedman for the shares of Enviro
on a one for one basis; (ii) the satisfactory completion of a "due diligence"
investigation by Enviro and Hedman; (iii) the acquisition by Enviro of the
Vermiculite deposits set forth on Schedule A hereto prior to the
closing(Descriptions to be Provided); (iv) approval of Hedman's shareholders at
its upcoming annual and special meeting of its shareholders; (v) Canadian
securities regulatory approvals (including Ontario and Alberta Securities
Commissions and CDNX Exchange approval); (vi) the transaction having no material
adverse tax effect on the parties hereto and their respective shareholders;
(vii) the exercise of the outstanding Warrants by Hedman's warrantholders unless
Enviro is able to exchange Enviro warrants for the Warrants in compliance with
the Act; and (viii) the obtaining of any material third party consents by either
party. Anything to the contrary herein notwithstanding, the parties further
agree as follows:

                  (a) Execution of a Definitive Agreement. There shall be
executed among Hedman and Enviro, definitive agreements (the "Agreement and Plan
of Reorganization") covering the proposed transaction under the terms and
conditions set forth in this
<PAGE>   3
letter and such further terms, provisions, agreements, covenants,
representations and warranties satisfactory to all parties, including:

                           (i) general warranties as to the contracts,
commitments, lease obligations, patents, trademarks, technology and debts of
Enviro and Hedman; and

                           (ii) representations, indemnifications and covenants
which shall survive the effective date of the transaction and which will, in the
opinion of the parties, be customary for transactions of this nature in respect
of the time, scope and subject matter and be adequate to protect their
respective interests.

                  (b) Litigation. Except as disclosed in Schedule B, neither
Enviro nor Hedman shall be subject to material litigation which would cause any
party, in its sole discretion, to decide that the party subject to such
litigation has a material contingent liability.

                  (c) Preservation of Assets of Business.

                           (i) Pending the closing date of the proposed
transaction, neither Enviro nor Hedman will incur any indebtedness other than in
the ordinary course of business and will not commit to any material
undertakings, programs or projects, other than pursuant to existing agreements,
which would have a material negative impact to their balance sheets without the
prior written consent of the other party. Other than paying current liabilities,
Enviro and Hedman will operate their businesses in a manner consistent with the
conservation of their assets including their cash reserves.

                           (ii) Enviro will have no liabilities at closing
except for those liabilities set forth on Schedule C and liabilities for legal
fees and transfer agent expenses incurred by Enviro after the signing of this
letter of intent in connection with the Acquisition.

                           (iii) Hedman will have no liabilities at closing
except for those liabilities set forth on Schedule D and liabilities for legal
fees and transfer agent expenses incurred by Hedman after the signing of this
letter of intent in connection with the Acquisition.

                                       3
<PAGE>   4
                  (d) Access to Books and Records. Pending the execution of the
Agreement and Plan of Reorganization and the consummation of the Acquisition,
Enviro and Hedman shall give each other or their designated representatives,
full access to their books of original entry, ledgers, bank statements, minute
books, stockholder lists, contracts, patents, trademarks and all other documents
maintained by them in connection with their business operations. Enviro shall
furnish Hedman or its counsel, with copies of Enviro's Articles of
Incorporation, By-laws, board minutes, shareholders minutes, stock ledgers and
such other documents that Hedman might reasonably request. Hedman shall furnish
Enviro or its counsel with copies of Hedman's Articles of Incorporation,
By-laws, board minutes, shareholders minutes, stock ledgers, contracts, purchase
orders, license agreements and such other documents that Enviro might reasonably
request, all such information being confidential and not to be used or disclosed
by either party except as permitted in the Agreement and Plan of Reorganization.

         (4) Financial Statements. Hedman agrees, upon the execution hereof to
provide Enviro with audited financial statements as of the end of its two most
recent fiscal years and Enviro will provide Hedman with unaudited financial
statements as at the closing or as at such earlier date acceptable to the
parties.

         (5) Expenses of Parties. Hedman, its shareholders and Enviro shall each
bear their own costs and expenses incurred if the proposed transaction is
abandoned at any time prior to the consummation thereof.

         (6) Public Announcement. Upon the execution of this Letter of Intent,
Enviro and Hedman shall prepare a public announcement to be submitted to the
media and/or regulatory agencies, as required by law, in such form and contain
such information as approved by Enviro and Hedman and as otherwise required by
law.

         (7) Other Matters.

                  (a) The closing of the Acquisition shall be completed on the
date on which the common stock of Enviro commences trading on the OTC Bulletin
Board, unless otherwise mutually agreed.

                  (b) At the closing, the Board of Directors of the Company
shall consist of five (5) persons three (3) of whom shall be selected by Hedman
and two (2) of whom shall be selected by
<PAGE>   5
Enviro. Thereafter, the Board of Directors shall be selected by the shareholders
in compliance with Delaware law.

                  (c) Hedman and Enviro acknowledge that this letter of intent
has been approved by their respective Boards of Directors.

                  (d) Officers' and Directors' Questionnaires for the officers
and directors of Hedman shall be furnished to Enviro upon request.

                  This letter outlines the major terms of the agreement between
our respective companies. Subject only to the conditions set forth in Section
(3) hereof, this Letter shall constitute the binding agreement of both Hedman
and Enviro. It is understood that on the basis of the foregoing understanding
concerning major terms, the parties shall begin negotiations of the Agreement
and Plan of Reorganization with the view to consummating the Acquisition as
promptly as possible.

                  If this letter reflects your understanding, please execute the
enclosed copy in the space provided below and return it to us.

Very truly yours,

Enviro Industrial Technologies, Inc.

By___________________________________                Dated: June 5, 2000
  Teodosio V. Pangia, Chairman

Agreed and Accepted:

Hedman Resources Limited

By___________________________________                Dated: June 5, 2000
  Claude Taillefer
<PAGE>   6
  CEO and President

                                       6<PAGE>   1
                                                                     EXHIBIT 4.1

                                NRG ENERGY, INC.

                                       and

                              THE BANK OF NEW YORK

                                   as Trustee

                             SENIOR DEBT SECURITIES
                                    INDENTURE

                           Dated as of March 13, 2001

<PAGE>   2

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>

                                                                                                   Page
                                                                                                   ----

<S>                                                                                              <C>
ARTICLE I DEFINITIONS................................................................................1

          Section 1.1   Certain Terms Defined........................................................1

ARTICLE II ISSUE, EXECUTION, FORM AND REGISTRATION OF SECURITIES.....................................7

          Section 2.1   Form and Dating of Securities................................................7

          Section 2.2   Execution and Authentication of Securities...................................8

          Section 2.3   Certificate of Authentication...............................................10

          Section 2.4   Form, Denomination and Date of Securities; Payments of Interest.............10

          Section 2.5   Global Securities...........................................................12

          Section 2.6   Registration, Registration of Transfer and Exchange.........................13

          Section 2.7   Mutilated, Defaced, Destroyed, Lost and Stolen Securities...................14

          Section 2.8   Cancellation of Securities; Destruction Thereof.............................15

          Section 2.9   Temporary Securities........................................................15

          Section 2.10  Computation of Interest.....................................................15

ARTICLE III COVENANTS OF THE ISSUER.................................................................16

          Section 3.1   Payment of Principal and Interest...........................................16

          Section 3.2   Offices for Payments, etc...................................................16

          Section 3.3   Appointment to Fill Vacancy in Office of Trustee............................16

          Section 3.4   Paying Agents...............................................................16

          Section 3.5   Certificate to Trustee......................................................17

          Section 3.6   Securityholder's Lists......................................................18

          Section 3.7   Reports by the Issuer.......................................................18

          Section 3.8   Limitation on Liens.........................................................18
</TABLE>

                                       i
<PAGE>   3

                           TABLE OF CONTENTS (CONT'D)

<TABLE>

<S>                                                                                            <C>
          Section 3.9   Repurchase of Securities Upon a Change of Control...........................19

ARTICLE IV REMEDIES OF THE TRUSTEE AND SECURITYHOLDERS ON EVENT OF DEFAULT..........................20

          Section 4.1   Event of Default Defined; Acceleration of Maturity; Waiver
                  of Default........................................................................20

          Section 4.2   Collection of Indebtedness by Trustee; Trustee May Prove Debt...............22

          Section 4.3   Application of Proceeds.....................................................24

          Section 4.4   Suits for Enforcement.......................................................25

          Section 4.5   Restoration of Rights on Abandonment of Proceedings.........................25

          Section 4.6   Limitations of Suits by Securityholders.....................................25

          Section 4.7   Powers and Remedies Cumulative, Delay or Omission Not Waiver
                  of Default........................................................................26

          Section 4.8   Control by Securityholders..................................................26

          Section 4.9   Waiver of Past Defaults.....................................................27

          Section 4.10  Rights of Holders to Receive Payment........................................27

ARTICLE V CONCERNING THE TRUSTEE....................................................................28

          Section 5.1   Duties and Responsibilities of the Trustee; During Default; Prior to
                  Default...........................................................................28

          Section 5.2   Certain Rights of the Trustee...............................................29

          Section 5.3   Trustee Not Responsible for Recitals, Disposition of Securities or
                  Application of Proceeds Thereof...................................................30

          Section 5.4   Trustee and Agents May Hold Securities; Collections, etc....................30

          Section 5.5   Moneys Held by Trustee......................................................31

          Section 5.6   Compensation and Indemnification of Trustee and Its Prior Claim.............31

          Section 5.7   Right of Trustee to Rely on Officers' Certificate, etc......................32

          Section 5.8   Persons Eligible for Appointment as Trustee.................................32

          Section 5.9   Resignation and Removal; Appointment of Successor Trustee...................32
</TABLE>

                                       ii
<PAGE>   4
                           TABLE OF CONTENTS (CONT'D)

<TABLE>

<S>                                                                                             <C>
          Section 5.10  Acceptance of Appointment by Successor Trustee..............................33

          Section 5.11  Merger, Conversion, Consolidation or Succession to
                  Business of Trustee...............................................................34

ARTICLE VI CONCERNING THE SECURITYHOLDERS...........................................................34

          Section 6.1   Evidence of Action Taken by Securityholders.................................34

          Section 6.2   Proof of Execution of Instruments and of Holding of Securities
                  Record Date.......................................................................35

          Section 6.3   Holders to be Treated as Owners.............................................35

          Section 6.4   Securities Owned by Issuer Deemed Not Outstanding...........................35

          Section 6.5   Right of Revocation of Action Taken.........................................36

ARTICLE VII SUPPLEMENTAL INDENTURES.................................................................36

          Section 7.1   Supplemental Indentures Without Consent of Securityholders..................36

          Section 7.2   Supplemental Indentures With Consent of Securityholders.....................37

          Section 7.3   Effect of Supplemental Indenture............................................38

          Section 7.4   Documents to be Given to Trustee............................................39

          Section 7.5   Notation of Securities in Respect of Supplemental Indentures................39

ARTICLE VIII CONSOLIDATE, MERGER, SALE OR CONVEYANCE................................................39

          Section 8.1   Covenant Not to Merge, Consolidate, Sell or Transfer Assets
                  Except Under Certain Conditions...................................................39

          Section 8.2   Successor Corporation Substituted...........................................40

          Section 8.3   Opinion of Counsel to Trustee; Officers' Certificate........................40

ARTICLE IX SATISFACTION AND DISCHARGE OF INDENTURE; UNCLAIMED MONEYS................................40

          Section 9.1   Satisfaction and Discharge of Indenture.....................................40

          Section 9.2   Application by Trustee of Funds Deposited for Payment of
                  Securities........................................................................41

          Section 9.3   Repayment of Moneys Held by Paying Agent....................................42
</TABLE>

                                      iii
<PAGE>   5

                           TABLE OF CONTENTS (CONT'D)

<TABLE>

<S>                                                                                             <C>
          Section 9.4   Return of Moneys Held by Trustee and Paying Agent Unclaimed
                  for Two Years.....................................................................42

          Section 9.5   Defeasance and Discharge of Indenture.......................................42

          Section 9.6   Defeasance of Certain Obligations...........................................43

ARTICLE X MISCELLANEOUS PROVISIONS..................................................................44

          Section 10.1  Incorporators, Shareholders, Officers and Directors of
                  Issuer Exempt from Individual Liability...........................................44

          Section 10.2  Provisions of the Indenture for the Sole Benefit of
                  Parties and Securityholders.......................................................45

          Section 10.3  Successors and Assigns of Issuer Bound by Indenture.........................45

          Section 10.4  Notices and Demands on Issuer, Trustee and Securityholders..................45

          Section 10.5  Officers' Certificates and Opinions of Counsel, Statements
                  to be Contained Therein...........................................................46

          Section 10.6  Payments Due on Saturdays, Sundays and Holidays.............................47

          Section 10.7  New York Law to Govern......................................................47

          Section 10.8  Counterparts................................................................47

          Section 10.9  Effect of Headings..........................................................47

ARTICLE XI REDEMPTION OF SECURITIES.................................................................47

          Section 11.1  Right of Optional Redemption Price..........................................47

          Section 11.2  Notice of Redemption........................................................47

          Section 11.3  Payment of Securities Called for Redemption.................................48
</TABLE>

                                       iv
<PAGE>   6

                           TABLE OF CONTENTS (CONT'D)

                Cross-reference sheet showing the location in this Indenture
of the provisions inserted pursuant to Sections 310 through 318, inclusive, of
the Trust Indenture Act of 1939, as amended.

             Trust Indenture                            Indenture Section
             Act Section                                -----------------
             -----------

         Section 310(a)(1)                              5.8
                    (a)(2)                              5.8
                    (a)(3)                              N/A
                    (a)(4)                              N/A
                    (a)(5)                              5.8
                    (b)                                 5.9
                    (c)                                 N/A

         Section 311(a)                                 5.5
                    (b)                                 N/A
                    (c)                                 N/A

         Section 312(a)                                 3.4
                    (b)                                 N/A
                    (c)                                 N/A

         Section 313(a)                                 N/A
                    (b)                                 N/A
                    (c)                                 N/A
                    (d)                                 N/A

         Section 314(a)                                 3.7
                    (b)(1)                              N/A
                    (b)(2)                              N/A
                    (c)(1)                              10.5
                    (c)(2)                              10.5
                    (c)(3)                              N/A
                       (d)                              N/A
                       (e)                              10.5
                       (f)                              N/A

         Section 315(a)                                 5.1(a)(i); 5.1(a)(ii)
                    (b)                                 N/A
                    (c)                                 5.1
                    (d)(1)                              5.1(a)(i); 5.1(a)(ii)
                    (d)(2)                              5.1(b)
                    (d)(3)                              5.1(c)

                                       i
<PAGE>   7

                           TABLE OF CONTENTS (CONT'D)

                    (e)                                 4.5

         Section 316(a)(1)(A)                           4.1(g); 4.8
                    (a)(1)(B)                           4.9
                    (a)(2)                              N/A
                    (b)                                 4.10
                    (c)                                 4.2(g)

         Section 317(a)(1)                              4.2
                    (a)(2)                              4.2(a)
                    (b)                                 10.2

         Section 318                                    7.1(e)

                                       ii
<PAGE>   8

         INDENTURE, dated as of March 13, 2001, between NRG ENERGY, INC., a
Delaware corporation (herein called the "Issuer"), and THE BANK OF NEW YORK, a
New York banking corporation, as trustee (herein called the "Trustee").

                              W I T N E S S E T H:

         WHEREAS, the Issuer has duly authorized the execution and delivery of
this Indenture to provide for the issuance from time to time of its debentures,
notes, bonds and other evidences of indebtedness (herein called the
"Securities"); and

         WHEREAS, all things necessary have been done to make this Indenture a
valid agreement of the Issuer, in accordance with its terms.

         NOW, THEREFORE:

         In consideration of the premises and the purchases of the Securities of
any Series (as defined herein) created and issued on or after the date hereof by
the Holders (as defined herein) thereof, the Issuer and the Trustee mutually
covenant and agree for the equal and proportionate benefit of the respective
Holders from time to time of the Securities of any Series, as follows:

                                    ARTICLE I
                                   DEFINITIONS

         Section 1.1       Certain Terms Defined.

         To the extent terms defined herein differ from any Authorizing
Resolution (as defined herein) or supplemental indenture pertaining to any
Series of Securities, the definitions in such Authorizing Resolution or
supplemental indenture will govern with respect to such Series. All accounting
terms used herein and not expressly defined shall have the meanings given to
them in accordance with GAAP (as defined herein). The words "herein," "hereof"
and "hereunder" and other words of similar import refer to this Indenture as a
whole and not to any particular Article, Section or other subdivision. The terms
defined in this Article include the plural as well as the singular.

         "Agent Members" has the meaning set forth in Section 2.4(b).

         "Authorizing Resolution" means a resolution adopted by the Board of
Directors or a committee of the Board of Directors or by an Officer or committee
of Officers pursuant to Board of Directors delegation authorizing a Series of
Securities.

         "Board of Directors" means either the Board of Directors of the Issuer
or any committee of such Board of Directors duly authorized to act on behalf of
such Board of Directors.

         "Business Day" means a day which is neither a legal holiday nor a day
on which banking institutions (including, without limitation, the Federal
Reserve System) are authorized or required by law or regulation to close in The
City of New York.

<PAGE>   9

         "Capital Stock" means, with respect, to any Person, any and all
outstanding shares, interests, participations or other equivalents (however
designated, whether voting or non-voting) of, or interests in (however
designated), the equity of such Person including, without limitation, all Common
Stock and Preferred Stock and partnership and joint venture interests of such
Person.

         "Change of Control" means the occurrence of one or more of the
following events: (i) a Person or group (as that term is used in Section
13(d)(3) of the Exchange Act) of Persons (other than Xcel) shall have become the
beneficial owner directly or indirectly, or shall have acquired the absolute
power to direct the vote, of more than 35% of the outstanding Voting Stock of
the Issuer or (ii) during any twelve-month period, individuals who at the
beginning of such period constitute the Board of Directors (together with any
new directors whose election or nomination was approved by a majority of the
directors then in office who were either directors at the beginning of such
period or who were previously so approved) shall cease for any reason to
constitute a majority of the Board of Directors. Notwithstanding the foregoing,
a Change of Control shall be deemed not to have occurred with respect to a
Series of Securities if one or more of the above events occurs or circumstances
exist and, after giving effect thereto, the Securities of such Series are rated
Investment Grade.

         "Change of Control Offer" has the meaning set forth in Section 3.9(b).

         "Clearstream" has the meaning set forth in Section 2.4(b).

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

         "Common Stock" means, with respect to any Person, Capital Stock of such
Person that does not rank prior, as to the payment of dividends or as to the
distribution of assets upon any voluntary or involuntary liquidation,
dissolution or winding up of such Person, to shares of any other class of
Capital Stock of such Person.

         "Consolidated Current Assets" and "Consolidated Current Liabilities"
mean such assets and liabilities of the Issuer on a consolidated basis as shall
be determined in accordance with GAAP to constitute current assets and current
liabilities, respectively, provided that inventory shall be valued at the lower
of cost (using the average life method) or market.

         "Consolidated Net Tangible Assets" means, as of the date of
determination thereof, the total amount of all Issuer's assets determined on a
consolidated basis in accordance with GAAP as of such date less the sum of (a)
Issuer's consolidated current liabilities determined in accordance with GAAP and
(b) assets properly classified as intangible assets, in accordance with GAAP.

         "Consolidated Total Assets" means, as of the date of any determination
thereof, the total amount of all assets of the Issuer determined on a
consolidated basis in accordance with GAAP.

                                       2
<PAGE>   10

         "Corporate Trust Office" means the principal office of the Trustee at
which the corporate trust business of the Trustee shall, at any particular time,
be principally administered, which office is, at the date as of which this
Indenture is dated, located at 101 Barclay Street, Floor 21W, New York, New York
10286.

         "Euroclear" has the meaning set forth in Section 2.4(b).

         "Event of Default" means, with respect to a particular Series of
Securities, any event or condition specified as such in Section 4.1 hereof that
shall have continued for the period of time, if any, therein designated.

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

         "GAAP" means generally accepted accounting principles in the U.S.
applied on a basis consistent with the principles, methods, procedures and
practices employed in the preparation of the Issuer's audited financial
statements, including, without limitation, those set forth in the opinions and
pronouncements of the Accounting Principles Board of the American Institute of
Certified Public Accountants and statements and pronouncements of the Financial
Accounting Standards Board or in such other statements by such other entity as
approved by a significant segment of the accounting profession.

         "Global Security" has the meaning set forth in Section 2.4(b).

         "Holder," "Holder of Securities," "Securityholder" and other similar
terms mean the registered holder of any Security.

         "Indebtedness" has the meaning set forth in Section 3.8.

         "Indenture" means this Indenture as amended or supplemented from time
to time, including pursuant to any Authorizing Resolution or supplemental
indenture pertaining to any Series.

         "Intangible Assets" means, as of the date of determination thereof, all
assets of the Issuer properly classified as intangible assets determined on a
consolidated basis in accordance with GAAP.

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

         "Investment Banker" means an independent investment banking institution
of national standing selected by the Issuer.

         "Investment Grade" means, with respect to a Series of Securities, a
rating of "Baa3" or higher by Moody's Investors Service, Inc., and a rating of
"BBB-" or higher by Standard and Poor's Ratings Group (or, if either or both of
the foregoing rating agencies ceases to rate a Series of Securities for reasons
beyond the control of the Issuer, equivalent ratings by one or two (as the case
may be) other nationally recognized statistical rating organizations (as such
term is defined in Rule 15c3-1(c)(2)(vi)(F) under the Exchange Act)); provided
that if either of the foregoing

                                       3
<PAGE>   11
rating agencies shall change its ratings designations while a Series of
Securities is Outstanding, "Investment Grade" shall mean the lowest ratings
designation signifying "investment grade" issued by such agencies (or higher).

         "Issuer" means NRG Energy, Inc., a Delaware corporation, and, subject
to Article 8 hereof, its successors and assigns.

         "Make Whole Amount" means, with respect to a Security of a particular
Series at any time, the sum of the present values of the Remaining Scheduled
Payments discounted, on a semiannual basis (assuming a 360 day year consisting
of twelve 30-day months), at a rate equal to the Treasury Rate plus 25 basis
points. The Make Whole Amount shall be computed as of the third Business Day
prior to the applicable redemption date, and certified, by an Investment Banker.

         "Officer" means the Chairman of the Board of Directors, the President,
any Vice President, the Chief Financial Officer, the Treasurer, any Assistant
Treasurer, the Controller, the Secretary or any Assistant Secretary of the
Issuer.

         "Officers' Certificate" means a certificate signed on behalf of the
Issuer by the Chairman of the Board of Directors or the President or any Vice
President and by the Chief Financial Officer or the Secretary or any Assistant
Secretary or the Treasurer or any Assistant Treasurer of the Issuer and
delivered to the Trustee. Each such certificate shall include the statements
provided for in Section 10.5 hereof, if and to the extent required thereby.

         "Opinion of Counsel" means an opinion in writing signed by legal
counsel satisfactory to the Trustee, who may be an employee of or counsel to the
Issuer. Each such opinion shall include the statements provided for in Section
10.5 hereof, if and to the extent required thereby.

         "Original Issue Date" of any Security (or portion thereof) means the
earlier of (a) the date of such Security or (b) the date of any Security (or
portion thereof) in exchange for which such Security was issued (directly or
indirectly) on registration of transfer, exchange or substitution.

         "Outstanding", when used with reference to Securities, shall, subject
to the provisions of Section 6.4 hereof, mean, as of any particular time, all
Securities authenticated and delivered by the Trustee under this Indenture,
except:

                  1.       Securities theretofore canceled by the Trustee or
         delivered to the Trustee for cancellation, or which shall have been
         paid pursuant to Section 2.7 hereof (other than any such Securities in
         respect of which there shall have been presented to the Trustee proof
         satisfactory to it that such Securities are held by a bona fide
         purchaser in whose hands the Securities are valid obligations of the
         Issuer); and

                  2.       Securities, or portions thereof, for the payment or
         redemption of which moneys or direct obligations of the United States
         of America backed by its full faith and credit in the necessary amount
         shall have been deposited in trust with the Trustee or with any paying
         agent (other than the Issuer) or shall have been set aside, segregated
         and held in trust by the Issuer (if the Issuer shall act as its own
         paying agent), provided that if such

                                       4
<PAGE>   12

         Securities are to be redeemed prior to the maturity thereof, notice of
         such redemption shall have been herein provided, or provision
         satisfactory to the Trustee shall have been given as herein provided,
         or provision satisfactory to the Trustee shall have been made for
         giving such notice.

         "Person" means an individual, a corporation, a partnership, a limited
liability company, an association, a trust or any other entity or organization,
including a government or political subdivision or an agency or instrumentality
thereof.

         "Preferred Stock" means, with respect to any Person, any and all
shares, interests, participation or other equivalents (however designated,
whether voting or non-voting) of preferred or preference Capital Stock of such
Person that is outstanding or issued on or after the date of this Indenture.

         "Remaining Scheduled Payments" means the remaining scheduled payments
of the principal and interest that would be due if such Security were not
redeemed. However, if the redemption date is not a scheduled interest payment
date, the amount of the next succeeding scheduled interest payment on such debt
security will be reduced by the amount of interest accrued on such Security to
such redemption date.

         "Repurchase Date" has the meaning set forth in Section 3.9(b).

         "Responsible Officer", when used with respect to the Trustee, means any
officer within the corporate trust department of the Trustee, including any vice
president, assistant vice president, assistant secretary, assistant treasurer,
trust officer or any other officer of the Trustee who customarily performs
functions similar to those performed by the Persons who at the time shall be
such officers, respectively, or to whom any corporate trust matter is referred
because of such person's knowledge of and familiarity with the particular
subject and who shall have direct responsibility for the administration of this
Indenture.

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

         "Security" or "Securities" has the meaning set forth in the recitals
above.

         "Securities Register" and "Security Registrar" have the respective
meanings specified in Section 2.6.

         "Series" means a series of Securities established under this Indenture.

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

         "Treasury Rate" means an annual rate equal to the semiannual equivalent
yield to maturity of the Comparable Treasury Issue (as defined below), assuming
a price for the Comparable Treasure Issue (expressed as a percentage of its
principal amount) equal to the Comparable Treasury Price (as defined below) for
the redemption date. The semiannual equivalent yield to

                                       5
<PAGE>   13

maturity will be computed as of the third Business day immediately preceding the
redemption date. "Comparable Treasury Issue" means the Unites States Treasury
security selected by Salomon Smith Barney or an affiliate as having a maturity
comparable to the remaining term of the notes that would be utilized, at the
time of selection and in accordance with customary financial practice, in
pricing new issues of corporate notes of comparable maturity to the remaining
term of the notes. "Comparable Treasury Price" means the average of three
Reverence Treasury Dealer Quotations (as defined below) obtained by the trustee
for the redemption date. "Reference Treasury Dealers" means Salomon Smith Barney
(so long as it continues to be a primary U.S. Government securities dealer) and
any two other primary U.S. Government securities dealers chosen by the Issuer.
If Salomon Smith Barney ceases to be a primary U.S. Government securities
dealers, the Issuer will appoint in its place another nationally recognized
investment banking firm that is a primary U.S. Government securities dealer.
"Reference Treasury Dealer Quotation" means the average, as determined by the
Trustee, of the bid and asked prices for the Comparable Treasury Issue
(expressed in each case as a percentage of its principal amount) quoted in
writing to the Trustee by a Reference Treasury Dealer at 3:30 p.m., New York
City time, on the third Business day preceding the redemption date.

         "Trust Indenture Act" means the Trust Indenture Act of 1939, as
amended.

         "Trustee" means the entity identified as "Trustee" in the first
paragraph hereof until the appointment of a successor trustee pursuant to
Article 5, after which "Trustee" shall mean such successor trustee.

         "U.S. Depositary" means The Depository Trust Company.

         "U.S. Government Obligations" means securities that are (i) direct and
unconditional 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, are not callable or redeemable at the option of the issuer thereof,
and shall also include a depository receipt issued by a bank or trust company
subject to federal or state supervision or examination with a combined capital
and surplus of at least $100,000,000, as custodian with respect to any such U.S.
Government Obligations or a specific payment of interest on or principal of any
such U.S. Government Obligation held by such custodian for the account of the
holder of a depository receipt, provided that (except as required by law) such
custodian is not authorized to make any deduction from the amount payable to the
holder of such depository receipt from any amount received by the custodian in
respect of the U.S. Government Obligation or the specific payment of interest on
or principal of the U.S. Government Obligation evidenced by such depository
receipt.

         "Voting Stock" means, with respect to any Person, Capital Stock of any
class or kind ordinarily having the power to vote for the election of directors
(or persons fulfilling similar responsibilities) of such Person.

         "Xcel" means Xcel Energy Inc., a Minnesota corporation.

                                       6
<PAGE>   14

                                   ARTICLE II
              ISSUE, EXECUTION, FORM AND REGISTRATION OF SECURITIES

         Section 2.1       Form and Dating of Securities.

         The aggregate principal amount of Securities that may be issued under
this Indenture is unlimited. The Securities may be issued from time to time in
one or more Series. Each Series shall be created by an Authorizing Resolution or
a supplemental indenture that establishes the terms of the Series, which may
include the following:

         (1)      the title of the Series;

         (2)      the aggregate principal amount (or any limit on the aggregate
                  principal amount) of the Series and, if any Securities of a
                  Series are to be issued at a discount from their face amount,
                  the method of computing the accretion of such discount;

         (3)      the interest rate or method of calculation of the interest
                  rate;

         (4)      the date from which interest will accrue;

         (5)      the record dates for interest payable on Securities of the
                  Series;

         (6)      the dates when, places where and manner in which principal and
                  interest are payable;

         (7)      the Securities Registrar;

         (8)      the terms of any mandatory (including any sinking fund
                  requirements) or optional redemption by the Company;

         (9)      the terms of any repurchase or remarketing rights of third
                  parties;

         (10)     the terms of any redemption at the option of Holders;

         (11)     the denominations in which Securities are issuable;

         (12)     whether Securities will be issued in registered or bearer form
                  and the terms of any such forms of Securities;

         (13)     whether any Securities will be represented by a Global
                  Security and the terms of any such Global Security;

         (14)     the currency or currencies (including any composite currency)
                  in which principal or interest or both may be paid;

                                       7
<PAGE>   15

         (15)     if payments of principal or interest may be made in a currency
                  other than that in which Securities are denominated, the
                  manner for determining such payments;

         (16)     provisions for electronic issuance of Securities or issuance
                  of Securities in uncertificated form;

         (17)     any Events of Default, covenants and/or defined terms in
                  addition to or in lieu of those set forth in this Indenture;

         (18)     whether and upon what terms Securities may be defeased if
                  different from the provisions set forth in this Indenture;

         (19)     the form of the Securities, which, unless the Authorizing
                  Resolution or supplemental indenture otherwise provides, shall
                  be in the form of Exhibit A;

         (20)     any terms that may be required by or advisable under
                  applicable law;

         (21)     the percentage of the principal amount of the Securities which
                  is payable if the maturity of the Securities is accelerated in
                  the case of Securities issued at a discount from their face
                  amount;

         (22)     whether any Securities will have guarantees; and

         (23)     any other terms in addition to or different from those
                  contained in this Indenture.

         All Securities of one Series need not be issued at the same time and,
unless otherwise provided, a Series may be reopened for issuances of additional
Securities of such Series pursuant to an Authorizing Resolution, an Officers'
Certificate or in any indenture supplemental hereto. The creation and issuance
of a Series and the authentication and delivery thereof are not subject to any
conditions precedent.

         The Securities shall be direct, unconditional obligations of the Issuer
and shall rank pari passu without preference among themselves and equally in
priority of payment with all other present and future unsubordinated, unsecured
indebtedness of the Issuer.

         Section 2.2       Execution and Authentication of Securities.

         The Securities shall be signed on behalf of the Issuer by both (a) its
Chairman of the Board of Directors or any Vice Chairman of the Board of
Directors or its President or any Vice President and (b) by its Chief Financial
Officer or its Secretary or its Assistant Secretary or its Treasurer or any
Assistant Treasurer, under its corporate seal which may, but need not, be
attested. Such signatures may be the manual or facsimile signatures of the
present or any future such officers. The seal of the Issuer may be in the form
of a facsimile thereof and may be impressed, affixed, imprinted or otherwise
reproduced on the Securities. Typographical and other minor errors or defects in
any such reproduction of the seal or any such signature shall not

                                       8
<PAGE>   16

affect the validity or enforceability of any Security that has been duly
authenticated and delivered by the Trustee.

         In case any officer of the Issuer who shall have signed any of the
Securities shall cease to be such officer before the Security so signed shall be
authenticated and delivered by the Trustee or disposed of by the Issuer, such
Security nevertheless may be authenticated and delivered or disposed of as
though the Person who signed such Security had not ceased to be such officer of
the Issuer; and any Security may be signed on behalf of the Issuer by such
Persons as, at the actual date of the execution of such Security, shall be the
proper officers of the Issuer, although at the date of the execution and
delivery of this Indenture any such Person was not such officer.
The Securities shall be delivered to the Trustee for authentication, and the
Trustee shall thereupon authenticate and deliver said Securities to or upon the
written order of the Issuer, signed by both (a) its Chairman of the Board of
Directors, or any Vice Chairman of the Board of Directors, or its President or
any Vice President and (b) by its Chief Financial Officer, or its Secretary or
any Assistant Secretary, or its Treasurer or any Assistant Treasurer without any
further action by the Issuer.

         In authenticating such Securities, and accepting the additional
responsibilities under this Indenture in relation to such Securities, the
Trustee shall be entitled to receive, and, subject to Section 5.1, shall be
fully protected in relying upon:

         (a)      A copy of the resolution or resolutions of the Board of
Directors in or pursuant to which the terms and form of the Securities were
established, certified by the Secretary or an Assistant Secretary of the Issuer
to have been duly adopted by the Board of Directors and to be in full force and
effect as of the date of such certificate, and if the terms and form of such
Securities are established by an Officers' Certificate pursuant to general
authorization of the Board of Directors, such Officers' Certificate;

         (b)      an executed supplemental indenture, if any;

         (c)      an Officers' Certificate delivered in accordance with Section
                  10.5; and

         (d)      an Opinion of Counsel which shall state:

                  (1)      that the form of such Securities has been established
         by a supplemental indenture or by or pursuant to a resolution of the
         Board of Directors in accordance with Sections 2.1 and 2.2 and in
         conformity with the provisions of this Indenture;

                  (2)      that the terms of such Securities have been
         established in accordance with Section 2.1 and in conformity with the
         other provisions of this Indenture;

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

                                       9
<PAGE>   17

                  (4)      that all laws and requirements in respect of the
         execution and delivery by the Issuer of such Securities have been
         complied with.

         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.

         Section 2.3       Certificate of Authentication.

         Only such Securities as shall bear thereon a certificate of
authentication substantially in the form recited in the form of Security
attached as Exhibit A hereto, executed by that Trustee by manual signature of
one of its authorized signatories, shall be entitled to the benefits of this
Indenture or be valid or obligatory for any purpose. Such certificate by the
Trustee upon any Security executed by the Issuer shall be conclusive evidence
that the Security so authenticated has been duly authenticated and delivered
hereunder and that the Holder is entitled to the benefits of this Indenture.

         Section 2.4       Form, Denomination and Date of Securities; Payments
of Interest.

         (a)      Any of the Securities may be issued with appropriate
insertions, omissions, substitutions and variations and may have imprinted or
otherwise reproduced thereon such legend or legends, not inconsistent with the
provisions of this Indenture, as may be required to comply with any law or with
any rules or regulations pursuant thereto, or with the rules of any securities
market in which the Securities are admitted to trading, or to conform to general
usage.

         (b)(i)   This Section 2.4(b)(i) shall apply only to Securities in
global form ("Global Securities") deposited with the U.S. Depositary.

         The Issuer shall execute and the Trustee shall, in accordance with this
Section 2.4(b)(i), authenticate and deliver initially Global Securities that (a)
shall be registered in the name of the U.S. Depositary for such Global
Securities or the nominee of such U.S. Depositary, (b) shall be deposited on
behalf of Agent Members (as defined herein) with the Trustee as custodian for
the U.S. Depositary and (c) shall bear legends substantially to the following
effect:

         "UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE
         OF [INSERT NAME AND ADDRESS OF U.S. DEPOSITARY] TO THE ISSUER OR ITS
         AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY
         CERTIFICATE ISSUED IN EXCHANGE FOR THIS CERTIFICATE OR ANY PORTION
         HEREOF IS REGISTERED IN THE NAME OF [INSERT NAME OF U.S. NOMINEE OF
         DEPOSITARY], OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
         REPRESENTATIVE OF [INSERT NAME OF U.S. DEPOSITARY], OR SUCH OTHER NAME
         AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF [INSERT NAME OF U.S.
         DEPOSITARY] (AND ANY PAYMENT HEREON IS MADE TO [INSERT NAME OF NOMINEE
         OF U.S. DEPOSITARY]), ANY TRANSFER, PLEDGE OR OTHER USE

                                       10
<PAGE>   18

         HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON OTHER THAN [INSERT
         NAME OF U.S. DEPOSITARY OR A NOMINEE THEREOF] IS WRONGFUL INASMUCH AS
         THE REGISTERED OWNER HEREOF, [INSERT NAME OF NOMINEE OF U.S.
         DEPOSITARY] HAS AN INTEREST HEREIN".

         "TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN
         WHOLE, BUT NOT IN PART, TO NOMINEES OF [INSERT NAME OF U.S. DEPOSITARY]
         OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF
         PORTIONS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS MADE IN
         ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN SECTION 2.6 OF THE
         INDENTURE REFERRED TO ON THE REVERSE HEREOF".

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

         (ii)  This Section 2.4(b)(ii) shall apply only to the Global Security
deposited on behalf of the purchasers of the Securities represented thereby with
the Trustee as custodian for the U.S. Depositary for credit to their respective
accounts (or to such other accounts as they may direct) at Euroclear System
("Euroclear") or Clearstream Banking, societe anonyme ("Clearstream") insofar as
interests in the Global Security are held by the Agent Members for Euroclear or
Clearstream.

         The provisions of the "Operating Procedures of the Euroclear System"
and the "Terms and Conditions Governing Use of Euroclear" and the "Management
Regulations" and "Instructions to Participants" of Clearstream, respectively,
shall be applicable to such Global Security insofar as interests therein are
held by the Agent Members for Euroclear and Clearstream. Account holders or
participants in Euroclear and Clearstream shall have no rights under this
Indenture with respect to the Global Security, and the nominee of the U.S.
Depositary may be treated by the Issuer and the Trustee and any agent of the
Issuer or the Trustee as the owner of the Global Security for all purposes
whatsoever. Notwithstanding the foregoing, nothing herein shall prevent the
Issuer, the Trustee or any agent of the Issuer or the Trustee from giving effect
to any written certification, proxy or other authorization furnished by the U.S.
Depositary or impair, as between the U.S. Depositary and its Agent Members, the
operation of customary practices governing the exercise of the rights of a
holder of any security.

         (c)   Each Security shall be dated the date of its authentication and
shall bear interest from the applicable date, and shall be payable on the dates
specified on the face of the form of Security attached as Exhibit A hereto.

                                       11
<PAGE>   19

         (d)      The Person in whose name any Security is registered at the
close of business on the record date specified in the Securities with respect to
any Interest Payment Date shall be entitled to receive the interest, if any,
payable on such Interest Payment Date notwithstanding any transfer or exchange
of such Security subsequent to the record date and prior to such Interest
Payment Date, except if and to the extent the Issuer shall default in the
payment of the interest due on such Interest Payment Date, in which case such
defaulted interest shall be paid to the Persons in whose names Outstanding
Securities are registered at the close of business on a subsequent special
record date, to be established (together with the related payment date) by the
Issuer with the consent of the Trustee. Such special record date shall not be
more than 15 nor less than 10 Business Days prior to the payment date. Not more
than 15 days prior to the special record date, the Issuer (or the Trustee, in
the name of and at the expense of the Issuer) shall mail to Holders a notice
that states the special record date, the related payment date and the amount of
interest to be paid. Notice of the proposed payment of such defaulted interest
and the special record date therefor having been mailed as aforesaid, such
defaulted interest shall be paid to the Persons in whose names the Securities
are registered on such special record date.

         Section 2.5       Global Securities.

         (a)      Portions of a Global Security deposited with the U.S.
Depositary pursuant to Section 2.4 shall be transferred in certificated form to
the beneficial owners thereof only if such transfer complies with Section 2.6 of
this Indenture and (i) the U.S. Depositary notifies the Issuer that it is
unwilling or unable to continue as U.S. Depositary for such Global Security or
if at any time such U.S. Depositary ceases to be a "clearing agency" registered
under the Exchange Act and a successor depositary is not appointed by the Issuer
within 90 days of such notice, or (ii) an Event of Default has occurred and is
continuing with respect to the Securities and payment of principal thereof and
interest thereon has been accelerated.

         (b)      Portions of any Global Security that are transferable to the
beneficial owners thereof pursuant to this Section 2.5 shall be surrendered by
the U.S. Depositary to the Trustee at its New York office for registration of
transfer, in whole or from time to time in part, without charge and the Trustee
shall authenticate and deliver, upon such registration of transfer of each
portion of such Global Security, an equal aggregate principal amount of
Securities of authorized denominations. Any portion of a Global Security whose
registration is transferred pursuant to this Section 2.5 shall be executed,
authenticated and delivered only in the denominations specified in the form of
Security attached as Exhibit A hereto and registered in such names as the U.S.
Depositary shall direct.

         (c)      Subject to the provisions of Section 2.4(b) above, the
registered Holder of any Global Security may grant proxies and otherwise
authorize any person, including Agent Members and persons that may hold
interests through Agent Members, to take any action which a Holder is entitled
to take under this Indenture or the Securities.

         (d)      In the event of the occurrence of any of the events specified
in paragraph (a) of this Section 2.5, the Issuer shall promptly make available
to the Trustee a reasonable supply of certificated Securities in definitive,
fully registered form without interest coupons.

                                       12
<PAGE>   20

         Section 2.6       Registration, Registration of Transfer and Exchange.

         (a)      The Issuer shall keep at each office or agency to be
maintained for the purpose as provided in Section 3.2 hereof a register or
registers (collectively referred to as the "Securities Register") in which,
subject to such reasonable regulations as it may prescribe, it will register or
cause to be registered, the transfer of Securities as provided in this Article.
The Trustee is hereby appointed "Security Registrar" for the purpose of
registering Securities and transfers of Securities as herein provided. If at any
time the Trustee shall not be serving as Security Registrar, at all reasonable
times such Securities Register shall be open for inspection by the Trustee.

         Upon due presentation for registration of transfer of any Security at
each such office or agency, the Issuer shall execute and the Trustee shall
authenticate and deliver in the name of the transferee or transferees a new
Security or Securities in authorized denominations for a like aggregate
principal amount.

         Any Security or Securities of a particular Series may be exchanged for
a Security or Securities of such particular Series in other authorized
denominations, in an equal aggregate principal amount. Securities to be
exchanged shall be surrendered at each office or agency to be maintained by the
Issuer for the purpose as provided in Section 3.2 hereof, and the Issuer shall
execute and the Trustee shall authenticate and deliver in exchange therefor the
Security or Securities which the Securityholder making the exchange shall be
entitled to receive, bearing numbers not contemporaneously outstanding.

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

         The Issuer or Trustee shall not be required to exchange or register a
transfer of (a) any Securities for a period of 15 days next preceding the first
mailing of notice of redemption of Securities to be redeemed or (b) any
Securities selected, called or being called for redemption except, in the case
of any Security where public notice has been given that such Security is to be
redeemed in part, the portion thereof not so to be redeemed.

         All Securities issued upon any registration of transfer or exchange of
Securities shall be valid obligations of the Issuer, evidencing the same debt,
and entitled to the same benefits under this Indenture, as the Securities
surrendered upon such registration of transfer or exchange.

         (b)      Notwithstanding any provision to the contrary herein, so long
as a Global Security remains outstanding and is held by or on behalf of the U.S.
Depositary, transfers of a Global Security, in whole or in part, shall only be
made (x) in the case of transfers of portions of a Global Security, to
beneficial owners thereof in certificated form, in accordance with Section 2.5,
and (y) in all other cases, in accordance with this Section 2.6(b).

         (c)      Successive registrations and registrations of transfers and
exchanges as aforesaid may be made from time to time as desired, and each such
registration shall be noted on the

                                       13
<PAGE>   21

Security Register. No service charge shall be made for any registration of
transfer or exchange of the Securities, but the Trustee may require payment of a
sum sufficient to cover any tax or other governmental charge payable in
connection therewith and any other amounts required to be paid by the provisions
of the Securities.

         (d)      The Trustee shall have no obligation or duty to monitor,
determine or inquire as to compliance with any restrictions on transfer imposed
under this Indenture or under applicable law with respect to any transfer of any
interest in any Security (including any transfers between or among Agent Members
or beneficial owners of interests in any Global Security) other than to require
delivery of such certificates and other documentation or evidence as are
expressly required by, and to do so if and when expressly required by the terms
of, this Indenture, and to examine the same to determine substantial compliance
as to form with the express requirements hereof.

         Section 2.7       Mutilated, Defaced, Destroyed, Lost and Stolen
Securities.

         In case any temporary or definitive Security shall become mutilated,
defaced or be apparently destroyed, lost or stolen, the Issuer in its discretion
may execute, and upon the written request any officer of the Issuer, the Trustee
shall authenticate and deliver a new Security, bearing a number not
contemporaneously outstanding, in exchange and substitution for the mutilated or
defaced Security, or in lieu of and substitution for Security so apparently
destroyed, lost or stolen. In every case the applicant for a substitute Security
shall furnish to the Issuer and to the Trustee and any agent of the Issuer or
the Trustee such security or indemnity as may be required by them to indemnify
and defend and to save each of them harmless and, in every case of destruction,
loss or theft, evidence to their satisfaction of the apparent destruction, loss
or theft of such Security and of the ownership thereof.

         Upon the issuance of a substitute Security, the Issuer may require the
payment of a sum sufficient to cover any tax or other governmental charge that
may be imposed in relation thereto and any other expenses (including the fees
and expenses of the Trustee) connected therewith. In case any Security which has
matured or is about to mature, or has been called for redemption in full, shall
become mutilated or defaced or be apparently destroyed, lost or stolen. the
Issuer may, instead of issuing a substitute Security, pay or authorize the
payment of the same (without surrender thereof except in the case of a mutilated
or defaced Security), if the applicant for such payment shall furnish to the
Issuer and to the Trustee and any agent of the Issuer or the Trustee such
security or indemnity as any of them may require to save each of them harmless
from all risks, however remote, and, in every case of apparent destruction, loss
or theft, the applicant shall also furnish to the Issuer and the Trustee and any
agent of the Issuer or the Trustee evidence to their satisfaction of the
apparent destruction, loss or theft of such Security and of the ownership
thereof.

         Every substitute Security issued pursuant to the provisions of this
Section by virtue of the fact that any Security is apparently destroyed, lost or
stolen shall constitute an additional contractual obligation of the Issuer,
whether or not the apparently destroyed, lost or stolen Security shall be at any
time enforceable by anyone and shall be entitled to all the benefits of (but
shall be subject to all the limitations of rights set forth in) this Indenture
equally and proportionately with any and all other Securities duly authenticated
and delivered hereunder. All

                                       14
<PAGE>   22

Securities shall be held and owned upon the express condition that, to the
extent permitted by law, the foregoing provisions are exclusive with respect to
the replacement or payment of mutilated, defaced, or apparently destroyed, lost
or stolen Securities and shall preclude any and all other rights or remedies
notwithstanding any law or statute existing or hereafter enacted to the contrary
with respect to the replacement or payment of negotiable instruments or other
securities without their surrender.

         Section 2.8       Cancellation of Securities; Disposition Thereof.

         All Securities surrendered for payment, redemption, registration of
transfer or exchange, if surrendered to the Issuer or any agent of the Issuer or
the Trustee, shall be delivered to the Trustee for cancellation or, if
surrendered to the Trustee, shall be canceled by it provided all conditions
regarding such cancellation have been met; and no Securities shall be issued in
lieu thereof except as expressly permitted by any of the provisions of this
Indenture. The Trustee shall cancel and dispose of all Securities surrendered
for registration of transfer, exchange, payment or cancellation in accordance
with the Trustee's policy of disposal. If the Issuer shall acquire any of the
Securities, such acquisition shall not operate as a redemption or satisfaction
of the indebtedness represented by such Securities unless and until the same are
delivered to the Trustee for cancellation.

         Section 2.9       Temporary Securities.

         Pending the preparation of definitive Securities, the Issuer may
execute and the Trustee shall authenticate and deliver temporary Securities
(printed, lithographed, typewritten or otherwise reproduced, in each case in
form satisfactory to the Trustee). Temporary Securities shall be issuable as
registered Securities without coupons, of any authorized denomination, and
substantially in the form of the definitive Securities but with such omissions,
insertions and variations as may be appropriate for temporary Securities, all as
may be determined by the Issuer with the concurrence of the Trustee. Temporary
Securities may contain such reference to any provisions of this Indenture as may
be appropriate. Every temporary Security shall be executed by the Issuer and be
authenticated by the Trustee upon the same conditions and in substantially the
same manner, and with like effect, as the definitive Securities. Without
unreasonable delay the Issuer shall execute and shall furnish definitive
Securities and thereupon temporary Securities may be surrendered in exchange
therefor without charge at each office or agency to be maintained by the Issuer
for the purpose pursuant to Section 3.2 hereof, and the Trustee shall
authenticate and deliver in exchange for such temporary Securities a like
aggregate principal amount of definitive Securities of authorized denominations.
Until so exchanged the temporary Securities shall be entitled to the same
benefits under this Indenture as definitive Securities.

         Section 2.10      Computation of Interest.

         Interest on the Securities shall be computed on the basis of a 360-day
year of twelve 30-day months.

                                       15
<PAGE>   23

                                   ARTICLE III
                             COVENANTS OF THE ISSUER

         To the extent that an Authorizing Resolution or supplemental indenture
pertaining to any Series provides for different provisions relating to the
subject matter of this Article Three, the provisions in such Authorizing
Resolution or supplemental indenture shall govern for purposes of such Series.

         Section 3.1       Payment of Principal and Interest.

         The Issuer covenants and agrees that it will duly and punctually pay or
cause to be paid the principal and Change of Control purchase price of, and
premium, if any, and interest on, each of the Securities at the place or places,
at the respective times and in the manner provided in the Securities. Payment of
principal and the Change of Control purchase price of, and premium and interest
on the Securities shall be paid by mailing a check to or upon the written order
of the registered Holders of Securities entitled thereto at their last address
as it appears on the Securities Register or, upon written application to the
Trustee by a Holder of $1,000,000 or more in aggregate principal amount of
Securities, by wire transfer of immediately available funds to an account
maintained by such Holder with a bank or other financial institution; provided,
however, that (subject to the provisions of Section 2.7 hereof) payment of
principal and the Change of Control Price of, and premium, if any, on, any
Security may be conditioned upon presentation for payment of the certificate
representing such Security.

         Section 3.2       Offices for Payments, etc.

         So long as any of the Securities remain Outstanding, the Issuer shall
maintain in the Borough of Manhattan, The City of New York, the following: (a)
an office or agency where the Securities may be presented for payment, (b) an
office or agency where the Securities may be presented for registration of
transfer and for exchange as in this Indenture provided and (c) an office or
agency where notices and demands to or upon the Issuer in respect of the
Securities or of this Indenture may be served. The Issuer shall give to the
Trustee written notice of the location of any such office or agency and of any
change of location thereof. The Issuer hereby initially designates the Trustee's
New York office as such office or agency. In case the Issuer shall fail to
maintain any such office or agency or shall fail to give such notice of the
location or of any change in the location thereof, presentations and demands may
be made and notices may be served at the Corporate Trust Office.

         Section 3.3       Appointment to Fill Vacancy in Office of Trustee.

         The Issuer, whenever necessary to avoid or fill a vacancy in the office
of Trustee, shall appoint, in the manner provided in Section 5.9 hereof, a
Trustee, so that there shall at all times be a Trustee hereunder.

         Section 3.4       Paying Agents.

         The Trustee shall be the principal paying agent for the Securities.
Whenever the Issuer shall appoint a paying agent other than the Trustee, it
shall cause such paying agent to execute

                                       16
<PAGE>   24

and deliver to the Trustee an instrument in which such agent shall agree with
the Trustee, subject to the provisions of this Section,

         (a)      that it will hold all sums received by it as such agent for
the payment of the principal or Change of Control purchase price of, or premium
or interest on, the Securities (whether such sums have been paid to it by the
Issuer or by any other obligor on the Securities) in trust for the benefit of
the Holders of the Securities or of the Trustee,

         (b)      that it will give the Trustee written notice of any failure
by the Issuer (or by any other obligor on the Securities) to make any payment of
the principal or Change of Control purchase price of, or premium or interest on,
the Securities when the same shall be due and payable and

         (c)      pay any such sums so held in trust by it to the Trustee upon
the Trustee's written request at any time during the continuance of the failure
referred to in clause (b) above.

         The Issuer shall, prior to each due date of the principal or Change of
Control purchase price of, and premium, if any, or interest on the Securities,
deposit with the paying agent a sum sufficient to pay such principal, Change of
Control purchase price, premium or interest, and (unless such paying agent is
the Trustee) the Issuer shall promptly notify the Trustee of any failure to take
such action.

         Anything in this Section 3.4 to the contrary notwithstanding, the
Issuer may at any time, for the purpose of obtaining satisfaction and discharge
of this Indenture or for any other reason, pay or cause to be paid to the
Trustee all sums held in trust by any paying agent hereunder, as required by
this Section 3.4, such sums to be held by the Trustee upon the trusts herein
contained.

         Anything in this Section to the contrary notwithstanding, the agreement
to hold sums in trust as provided in this Section 3.4 is subject to the
provisions of Section 9.3 and Section 9.1 hereof.

         Section 3.5       Certificate to Trustee; Statement by Officers as to
 Default.

         Issuer shall furnish to the Trustee on or before March 31 in each year
(beginning with March 31, 2001) a brief certificate from the principal
executive, financial or accounting officer of this Issuer as to his or her
knowledge of the Issuer's compliance with all covenants under this Indenture and
any supplemental indenture hereto (such compliance to be determined without
regard to any period of grace or requirement of notice provided under this
Indenture) and if the Issuer shall not be in compliance, specifying such
non-compliance and the nature and status thereof of which such signer may have
knowledge.

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

                                       17
<PAGE>   25

         Section 3.6       Securityholder's Lists.

         The Issuer shall furnish or cause to be furnished to the Trustee a list
in such form as the Trustee may reasonably require of the names and addresses of
the Holders of the Securities (a) semiannually not more than 15 days after each
record date for the payment of semi-annual interest on the Securities, as of
such record date and (b) at other times as the Trustee may request in writing,
within thirty days after receipt by the Issuer of any such request as of a date
not more than 15 days prior to the time such information is furnished.

         Section 3.7       Reports by the Issuer.

         The Issuer shall file with the Trustee and provide Securityholders,
within 15 days after it files them with the Commission, copies of its annual
reports and of the information, documents and other reports (or copies of such
portions of any of the foregoing as the Commission may by rules and regulations
prescribe) that the Issuer is required to file with the Commission pursuant to
Section 13 or 15(d) of Exchange Act. 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 Issuer's compliance with any of its covenants hereunder (as to which the
Trustee is entitled to rely exclusively on Officers' Certificates).

         Section 3.8       Limitation on Liens.

         So long as any of the Securities are Outstanding, the Issuer shall not
pledge, mortgage or hypothecate, or permit to exist, any mortgage, pledge or
other lien upon any property at any time directly owned by the Issuer to secure
any indebtedness for money borrowed that is incurred, issued, assumed or
guaranteed by the Issuer ("Indebtedness"), without making effective provisions
whereby the Securities shall be equally and ratably secured with any and all
such Indebtedness and with any other Indebtedness similarly entitled to be
equally and ratably secured; provided, however, that with respect to any Series
of Securities this restriction shall not apply to or prevent the creation or
existence of (i) liens existing at the Original Issuance Date of such Series of
Securities, (ii) purchase money liens that do not exceed the cost or value of
the purchased property, (iii) other liens not to exceed 10% of Consolidated Net
Tangible Assets, and (iv) liens granted in connection with extending, renewing,
replacing or refinancing, in whole or in part, the Indebtedness (including,
without limitation, increasing the principal amount of such Indebtedness)
secured by liens described in the foregoing clauses (i) through (iii).

         In the event that the Issuer shall propose to pledge, mortgage or
hypothecate any property at any time directly owned by it to secure any
Indebtedness, other than as permitted by clauses (i) through (iv) of the
previous paragraph, the Issuer shall (prior thereto) give written notice thereof
to the Trustee, who shall give notice to the Holders, and the Issuer shall,
prior to or simultaneously with such pledge, mortgage or hypothecation,
effectively secure all the Securities equally and ratably with such
Indebtedness.

                                       18
<PAGE>   26

         Section 3.9     Repurchase of Securities Upon a Change of Control.

         (a)      Upon a Change of Control, each Holder of Securities of a
Series to which the Change of Control applies shall have the right to require
that the Issuer repurchase such Holder's Securities at a repurchase price in
cash equal to 101% of the principal amount thereof plus accrued interest, if
any, to the date of repurchase, in accordance with the terms set forth in
subsection (b) below.

         (b)      Within 30 days following any Change of Control with respect to
Securities of a Series, the Issuer shall mail a notice to each Holder of such
Series (with a copy to the Trustee) stating:

                  (i)    that a Change of Control has occurred and that such
Holder has the right to require the Issuer to repurchase such Holder's
Securities at a repurchase price in cash equal to 101% of the principal amount
thereof plus accrued interest, if any, to the date of repurchase (the "Change of
Control Offer");

                  (ii)   the circumstances and relevant facts regarding such
Change of Control (including information with respect to pro forma historical
income, cash flow and capitalization of the Issuer after giving effect to such
Change of Control);

                  (iii)  the repurchase date (which shall be a Business Day and
be not earlier than 30 days or later than 60 days from the date such notice is
mailed) (the "Repurchase Date");

                  (iv)   that any Security not tendered for purchase will
continue to accrue interest;

                  (v)    that interest on any Security accepted for payment
pursuant to the Change of Control Offer shall cease to accrue after the
repurchase of such Security on the Repurchase Date;

                  (vi)   that Holders electing to have a Security purchased
pursuant to a Change of Control Offer will be required to surrender the
Security, with the form entitled "Option of Holder to Elect Purchase" on the
reverse of the Security completed, to the paying agent at the address specified
in the notice prior to the close of business on the third Business Day prior to
the Repurchase Date;

                  (vii)  that Holders will be entitled to withdraw their
election if the paying agent receives, not later than the close of business on
the third Business Day (or such shorter periods as may be required by applicable
law) preceding the Repurchase Date, a telegram, telex, facsimile transmission or
letter setting forth the name of the Holder, the principal amount of Securities
the Holder delivered for purchase, and a statement that such Holder is
withdrawing its election to have such Securities purchased; and

                  (viii) that Holders that elect to have their Securities
purchased only in part will be issued new Securities in a principal amount equal
to then unpurchased portion of the Securities surrendered.

                                       19
<PAGE>   27

         (c)      Notwithstanding the foregoing, for so long as the Securities
are in the form of Global Securities, the Issuer shall deliver to the U.S.
Depositary within the time periods specified above, for retransmittal to its
Agent Members, a notice substantially to the effect specified in clauses (1)
through (5) and (7) above, which notice shall also specify the required
procedures (furnished by the U.S. Depositary) for holders of interests in the
Global Securities to tender and receive payment of the purchase price for such
interests (including the U.S. Depositary's "Repayment Option Procedures," to the
extent applicable), all in accordance with the U.S. Depositary's rules,
regulations and practices.

         (d)      On the Repurchase Date, the Issuer shall (i) accept for
payment Securities or portions thereof tendered pursuant to the Change of
Control Offer, (ii) deposit with the Trustee money sufficient without
reinvestment to pay the purchase price of all Securities or portions thereof so
tendered and (iii) deliver or cause to be delivered to the Trustee Securities so
accepted together with an Officers' Certificate identifying the Securities or
portions thereof tendered to the Issuer. The Trustee shall promptly pay to the
Holders of the Securities so accepted an amount equal to the purchase price, and
promptly authenticate and mail to such Holders a new Security in a principal
amount equal to any unpurchased portion of the Security surrendered. The Issuer
will publicly announce the results of the Change of Control Offer on or as soon
as practicable after the Repurchase Date.

         (e)      The Issuer shall comply with Rule 14e-1 under the Exchange Act
and any other applicable laws and regulations in the event that a Change of
Control occurs and the Issuer is required to make a Change of Control Offer.

                                   ARTICLE IV
                           REMEDIES OF THE TRUSTEE AND
                       SECURITYHOLDERS ON EVENT OF DEFAULT

         Section 4.1       Event of Default Defined; Acceleration of Maturity;
                           Waiver of Default.

         In case of one or more of the following Events of Default with respect
to a Series of Securities (whatever the reason for such Event of Default and
whether it shall be voluntary or involuntary or be effected by operation of law
or pursuant to any judgment, decree or order of any court or any order, rule or
regulation of any administrative or governmental body) shall have occurred and
be continuing, that is to say:

         (a)      default in the payment of all or any part of the principal or
Change of Control purchase price of, or premium, if any, on, any of the
Securities of such Series as and when the same shall become due and payable
either at maturity, upon any redemption or required repurchase, by declaration
of acceleration or otherwise;

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

                                       20
<PAGE>   28

         (c)      an event of default, as defined in any instrument of the
Issuer under which there may be issued, or by which there may be secured or
evidenced, any Indebtedness of the Issuer that has resulted in the acceleration
of such Indebtedness, or any default occurring in payment of any such
Indebtedness at final maturity (and after the expiration of any applicable grace
periods), other than such Indebtedness (i) which is payable solely out of the
property or assets of a partnership, joint venture or similar entity of which
the Issuer is a participant, or which is secured by a lien on the property or
assets owned or held by such entity, without further recourse to or liability of
the Issuer, or (ii) the principal of, and interest on, which, when added to the
principal of and interest on all other such Indebtedness (exclusive of
Indebtedness under clause (i) above), does not exceed $50,000,000; or

         (d)      failure on the part of the Issuer duly to observe or perform
any other of the covenants or agreements on the part of the Issuer in the
Securities of such Series or in this Indenture and such failure continues for a
period of 30 days after the date on which written notice specifying such
failure, stating that such notice is a "Notice of Default" hereunder and
demanding that the Issuer remedy the same, shall have been given to the Issuer
by the Trustee, or to the Issuer and the Trustee by the Holders of at least 25%
in aggregate principal amount of such Series of Securities at the time
Outstanding; or

         (e)      a court having jurisdiction in the premises shall enter a
decree or order for relief in respect of the Issuer in an involuntary case or
proceeding under any applicable bankruptcy, insolvency, reorganization or other
similar law now or hereafter in effect, or a decree or order adjudging the
Issuer a bankrupt or insolvent, or approving as properly filed a petition
seeking reorganization, arrangement, adjustment, or composition of or in respect
of the Issuer under any applicable federal or state law, or appointing a
receiver, liquidator, assignee, custodian, trustee, sequestrator or similar
official of the Issuer or for any substantial part of its property or ordering
the winding up or liquidation of its affairs, shall have been entered, and such
decree or order shall remain unstayed and in effect for a period of 90
consecutive days; or

         (f)      the Issuer shall commence a voluntary case or proceeding under
any applicable federal or state bankruptcy, insolvency, reorganization or other
similar law now or hereafter in effect or of any other case or proceeding to be
adjudicated a bankrupt or insolvent, or consent to the entry of a decree or
order for relief in an involuntary case or proceeding under any such law, or to
the commencement of any bankruptcy or insolvency case or proceeding against the
Issuer, or the filing by the Issuer of a petition or answer or consent seeking
reorganization or relief under any such applicable federal or state law, or the
consent by the Issuer to the filing of such petition or to the appointment of or
the taking possession by a custodian, receiver, liquidator, assignee, trustee,
sequestrator or other similar official of the Issuer or of any substantial part
of its property, or the making by the Issuer of an assignment for the benefit of
creditors, or the taking of action by the Issuer in furtherance of any such
action;

         then and in each and every such case (other than an Event of Default
with respect to the Issuer specified in 4.1(e) or 4.1(f) hereof), unless the
principal of all of the Securities shall have already become due and payable,
either the Trustee or the Holders of not less than 25% in aggregate principal
amount of a particular Series of Securities then Outstanding hereunder, by
notice in writing to the Issuer (and to the Trustee if given by
Securityholders), may declare the

                                       21
<PAGE>   29

entire principal of all the Securities of such Series and the interest accrued
thereon to be due and payable immediately, and upon any such declaration the
same shall become immediately due and payable. This provision, however, is
subject to the condition that if, at any time after the principal of the
Securities of such Series shall have been so declared due and payable, and
before any judgment or decree for the payment of the moneys due shall have been
obtained or entered as hereinafter provided, the Issuer shall pay or shall
deposit with the Trustee a sum sufficient to pay all matured installments of
interest upon all the Securities of such Series and the principal or Change of
Control purchase price and premium, if any, of any and all Series of Securities
that shall have become due otherwise than by acceleration (with interest upon
such principal and Change of Control purchase price and premium, if any, and, to
the extent that payment of such interest is enforceable under applicable law, on
overdue installments of interest, at the rate of interest specified in the
Series of Securities, to the date of such payment or deposit) and such amount as
shall be sufficient to cover reasonable compensation to the Trustee and each
predecessor Trustee, their respective agents, attorneys and counsel, and all
other reasonable expenses and liabilities incurred and all reasonable advances
made, by the Trustee and each predecessor Trustee except as a result of gross
negligence or willful misconduct, and if any and all Events of Default under the
Indenture, other than the non-payment of the principal that shall have become
due by acceleration, shall have been cured, waived or otherwise remedied as
provided herein, then and in every such case the Holders of a majority in
aggregate principal amount of the Securities of such Series then Outstanding, by
written notice to the Issuer and to a Responsible Officer of the Trustee, may
waive all defaults (except, unless theretofore cured, a default in payment of
principal of, or Change of Control purchase price or premium, if any, or
interest on, the Securities of such Series) and rescind and annul such
declaration and its consequences, but no such waiver or rescission and annulment
shall extend to or shall affect any subsequent default or shall impair any right
consequent thereon.

         If an Event of Default specified in Section 4.1(e) or 4.1(f) hereof
occurs with respect to the Issuer, the principal of and accrued interest on the
Securities shall become and be immediately due and payable without any
declaration or other act on the part of the Trustee or any Securityholder.

         Section 4.2       Collection of Indebtedness by Trustee; Trustee May
Prove Debt.

         The Issuer covenants that (a) in case default shall be made in the
payment of any installment of interest on any of the Securities when such
interest shall have become due and payable, and such default shall have
continued for a period of 30 days or (b) in case default shall be made in the
payment of all or any part of the principal or Change of Control purchase price
of, or premium, if any, on, any of the Securities when the same shall have
become due and payable, whether upon maturity or upon any redemption or by
declaration or acceleration or otherwise, then upon demand of the Trustee, the
Issuer shall pay to the Trustee for the benefit of the Holders of the Securities
the whole amount that then shall have become due and payable on all such
Securities of principal. Change of Control purchase price, premium or interest,
as the case may be (with interest to the date of such payment upon the overdue
principal, Change of Control purchase price or premium and, to the extent that
payment of such interest is enforceable under applicable law, on overdue
installments of interest at the rate of interest specified in the Securities);
and in addition thereto, such further amount as shall be sufficient to cover the
costs and

                                       22
<PAGE>   30

expenses of collection, including reasonable compensation to the Trustee and
each predecessor Trustee, their respective agents, attorneys and counsel, and
any reasonable expenses and liabilities incurred, and all reasonable advances
made, by the Trustee and each predecessor Trustee except as a result of its
gross negligence or willful misconduct.

         Until such demand is made by the Trustee, the Issuer may pay the
principal and Change of Control purchase price of and premium and interest on
the Securities to the registered Holders, whether or not the Securities be
overdue.

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

         In case there shall be pending proceedings relative to the Issuer or
any other obligor upon the Securities under Title 11 of the United States Code
or any other applicable federal or state bankruptcy, insolvency or other similar
law, or in case a receiver, assignee or trustee in bankruptcy or reorganization,
liquidator, custodian, sequestrator or similar official shall have been
appointed for or taken possession of the Issuer or its property or such other
obligor, or in case of any other comparable judicial proceedings relative to the
Issuer or other obligor upon the Securities, or to the creditors or property of
the Issuer or such other obligor, the Trustee, irrespective of whether the
principal of the Securities shall then be due and payable as therein expressed
or by declaration or otherwise and irrespective or whether the Trustee shall
have made any demand pursuant to the provisions of this Section 4.2, shall be
entitled and empowered, by intervention in such proceedings or otherwise:

         (a)      to file and prove a claim or claims for the whole amount of
principal, Change of Control purchase price, premium and interest owing and
unpaid in respect of the Securities, and to file such other papers or documents
as may be necessary or advisable in order to have the claims of the Trustee
(including any claim for reasonable compensation to the Trustee and each
predecessor Trustee, and their respective agents, attorneys and counsel, and for
reimbursement of all reasonable expenses and liabilities incurred, and all
reasonable advances made, by the Trustee and each predecessor Trustee, except as
a result of gross negligence or willful misconduct) and of the Securityholders,
allowed in any judicial proceedings relative to the Issuer or other obligor upon
the Securities, or to the creditors or property of the Issuer or such other
obligor;

         (b)      unless prohibited by applicable law and regulations, to vote
on behalf of the Holders of the Securities in any election of a trustee or a
standby trustee in arrangement, reorganization, liquidation or other bankruptcy
or insolvency proceedings or person performing similar functions in comparable
proceedings; and

         (c)      to collect and receive any moneys or other property payable or
deliverable on any such claims, and to distribute all amounts received with
respect to the claims of the Securityholders and of the Trustee on their behalf;
and any trustee, receiver, or liquidator,

                                       23
<PAGE>   31

custodian or other similar official is hereby authorized by each of the
Securityholders to make payments to the Trustee, and, in the event that the
Trustee shall consent to the making of payments directly to the Securityholders,
to pay to the Trustee such amounts as shall be sufficient to cover reasonable
compensation to the Trustee, each predecessor Trustee and their respective
agents, attorneys and counsel, and all other reasonable expenses and liabilities
incurred, and all reasonable advances made, by the Trustee and each predecessor
Trustee except as a result of gross negligence or willful misconduct.

         Nothing herein contained shall be deemed to authorize the Trustee to
authorize or consent to or vote for or accept or adopt on behalf of any
Securityholders any plan or 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 Securityholder in
any such proceeding except, as aforesaid, to vote for the election of a trustee
in bankruptcy or similar person.

         All rights of action and of asserting claims under this Indenture, or
under any of the Securities, may be enforced by the Trustee without the
possession of any of the Securities or the production thereof at any trial or
other proceedings relative thereto, and any such action or proceedings
instituted by the Trustee shall be brought in its own name as trustee of an
express trust, and any recovery of judgment, subject to the payment of the
expenses, disbursements and compensation of the Trustee, each predecessor
Trustee and their respective agents and attorneys, shall be for the ratable
benefit of the Holders of the Securities.

         In any proceedings brought by the Trustee (and also any proceedings
involving the interpretation of any provision of this Indenture to which the
Trustee shall be a party) the Trustee shall be held to represent all the Holders
of the Securities, and it shall not be necessary to make any Holders of the
Securities parties to any such proceedings.

         Section 4.3       Application of Proceeds.

         Any moneys collected by the Trustee pursuant to this Article shall be
applied in the following order at the date or dates fixed by the Trustee and, in
case of the distribution of such moneys on account of principal or interest,
upon presentation of the several Securities and stamping (or otherwise noting)
thereon the payment, or issuing Securities in reduced principal amounts in
exchange for the presented Securities if only partially paid, or upon surrender
thereof if fully paid:

         FIRST: To the payment of costs and expenses, including reasonable
compensation to the Trustee and each predecessor Trustee and their respective
agents and attorneys and of all reasonable expenses and liabilities incurred,
and all reasonable advances made, by the Trustee and each predecessor Trustee
except as a result of gross negligence or willful misconduct and all other
amounts due under Section 5.6 hereof;

         SECOND: In case the principal and the Change of Control purchase price
and premium, if any, of the Securities shall not have become and be then due and
payable, to the payment of interest in default in the order of the maturity of
the installments of such interest, with interest (to the extent that such
interest has been collected by the Trustee) upon the overdue installments of

                                       24
<PAGE>   32

interest at the rate of interest specified in the Securities, such payments to
be made ratably to the persons entitled thereto, without discrimination or
preference;

         THIRD: In case the principal or the Change of Control purchase price of
the Securities shall have become and shall be then due and payable, to the
payment of the whole amount then owing and unpaid upon all the Securities for
principal, Change of Control purchase price, premium, and interest, with
interest upon the overdue principal, Change of Control purchase price, premium,
if any, and (to the extent that such interest has been collected by the Trustee)
upon overdue installments of interest at the rate of interest specified in the
Securities, and in case such moneys shall be insufficient to pay in full the
whole amount so due and unpaid upon the Securities, then to the payment of such
principal, Change of Control purchase price, premium and interest, without
preference or priority of principal, Change of Control purchase price or premium
over interest, or of interest over principal or Change of Control purchase price
or premium, or of any installment of interest over any other installment of
interest, or of any Security over any other Security, ratably to the aggregate
of such principal and accrued and unpaid interest; and

         FOURTH: To the payment of the remainder, if any, to the Issuer or any
other Person lawfully entitled thereto.

         The Trustee may fix a record date and payment date for any payment to
Securityholders pursuant to this Section 4.3.

         Section 4.4       Suits for Enforcement.

         In case an Event of Default has occurred, has not been waived and is
continuing, the Trustee may in its discretion proceed to protect and enforce the
rights vested in it by this Indenture by such appropriate judicial proceedings
as the Trustee shall deem most effectual to protect and enforce any of such
rights, either at law or in equity or in bankruptcy or otherwise, whether for
the specific enforcement of any covenant or agreement contained in this
Indenture or in aid of the exercise of any power granted in this Indenture or to
enforce any other legal or equitable right vested in the Trustee by this
Indenture or by law.

         Section 4.5       Restoration of Rights on Abandonment of Proceedings.

         In case the Trustee shall have proceeded to enforce any right under
this Indenture and such proceedings shall have been discontinued or abandoned
for any reason, or shall have been determined adversely to the Trustee, then and
in every such case the Issuer and the Trustee shall be restored respectively to
their former positions and rights hereunder, and all rights, remedies and powers
of the Issuer, the Trustee and the Securityholders shall continue as though no
such proceedings had been taken.

         Section 4.6       Limitations of Suits by Securityholders.

         No Holder of any Security of a Series shall have any right by virtue or
by availing of any provision of this Indenture to institute any action or
proceeding at law or in equity or in bankruptcy or otherwise upon or under or
with respect to this Indenture or the Series, or for the

                                       25
<PAGE>   33

appointment of a trustee, receiver, liquidator, custodian or other similar
official or for any other remedy hereunder, unless such Holder previously shall
have given to a responsible Officer of the Trustee written notice of default and
of the continuance thereof, as hereinbefore provided, and unless also the
Holders of not less than 25% in aggregate principal amount of the Securities of
the Holder's Series then Outstanding shall have made written request upon the
Trustee to institute such action or proceedings in its own name as trustee
hereunder and shall have offered to the Trustee such indemnity as it may
reasonably require against the costs, expenses and liabilities to be incurred
therein or thereby and the Trustee for 30 days after its receipt of such notice,
request and offer of indemnity shall have failed to institute any such action or
proceedings and no direction inconsistent with such written request shall have
been given to the Trustee pursuant to Section 4.8 hereof; it being understood
and intended, and being expressly covenanted by the taker and Holder of every
Security with every other taker and Holder and the Trustee, that no one or more
Holders of Securities shall have any right in any manner whatever by virtue or
by availing of any provision of this Indenture to affect, disturb or prejudice
the rights of any other Holder of Securities, or to obtain or seek to obtain
priority over or preference to any other such Holder or to enforce any fight
under this indenture, except in the manner herein provided and for the equal,
ratable and common benefit of all Holders of Securities. For the protection and
enforcement of the provisions of this Section 4.6 each and every Securityholder
and the Trustee shall be entitled to such relief as can be given either at law
or in equity.

         Section 4.7     Powers and Remedies Cumulative, Delay or Omission Not
                         Waiver of Default

         Except as provided in Section 2.7 hereof, no right or remedy herein
conferred upon or reserved to the Trustee or to the Securityholders is intended
to be exclusive of any other right or remedy, and every right and remedy shall,
to the extent permitted by law, be cumulative and in addition to every other
right and remedy given hereunder or now or hereafter existing at law or in
equity or otherwise. The assertion or employment of any right or remedy
hereunder, or otherwise, shall not prevent the concurrent assertion or
employment of any other appropriate right or remedy.

         No delay or omission of the Trustee or of any Holder of any of the
Securities to exercise as aforesaid any such right or power accruing upon any
Event of Default occurring and continuing as aforesaid shall impair any such
right or power or shall be construed to be a waiver of any such Event of Default
or an acquiescence therein; and, subject to Section 4.6 hereof, every power and
remedy given by this Indenture or by law to the Trustee or to the
Securityholders may be exercised from time to time, and as often as shall be
deemed expedient, by the Trustee or by the Securityholders.

         Section 4.8       Control by Securityholders.

         The Holders of a majority in aggregate principal amount of the
Securities of a Series at the time Outstanding shall have the right to direct
the time, method and place of conducting any proceeding for any remedy available
to the Trustee, or exercising any trust or power conferred on the Trustee by
this Indenture; provided that such direction shall not be otherwise than in
accordance with law and the provisions of this Indenture; and provided further
that (subject to the provisions of Section 5.1 hereof) the Trustee shall have
the right to decline to follow any

                                       26

<PAGE>   34

such direction if the Trustee, being advised by counsel, shall determine that
the action or proceeding so directed may not lawfully be taken or if the Trustee
in good faith by its board of directors, the executive committee, or a trust
committee of directors or Responsible Officers of the Trustee shall determine
that the action or proceedings so directed would involve the Trustee in personal
liability or if the Trustee in good faith shall so determine that the actions or
forbearances specified in or pursuant to such direction shall be unduly
prejudicial to the interests of Holders of the Securities of a Series not
joining in the giving of said direction, it being understood that (subject to
Section 5.1 hereof) the Trustee shall have no duty to ascertain whether or not
such actions or forbearances are unduly prejudicial to such Holders.

         Nothing in this Indenture shall impair the right of the Trustee to take
any action deemed proper by the Trustee and which is not inconsistent with such
direction by Securityholders.

         Section 4.9    Waiver of Past Defaults.

         Prior to the declaration of the maturity of the Securities of a Series
as provided in Section 4.1 hereof, the Holders of a majority in aggregate
principal amount of the Securities of such Series at the time Outstanding may on
behalf of the Holders of all the Securities of such Series waive any past
default or Event of Default hereunder and its consequences, except a default (a)
in the payment of principal or Change of Control purchase price of, premium, if
any, or interest on any of the Securities or (b) in respect of a covenant or
provision hereof that cannot be modified or amended without the consent of the
Holder of each Security affected. In the case of any such waiver, the Issuer,
the Trustee and the Holders of the Securities of such Series shall be restored
to their former positions and rights hereunder, respectively; but no such waiver
shall extend to any subsequent or other default or impair any right consequent
thereon.

         Upon any such waiver, such default shall cease to exist and be deemed
to have been cured and not to have occurred, and any Event of Default arising
therefrom shall be deemed to have been cured, and not to have occurred for every
purpose of this Indenture; but no such waiver shall extend to any subsequent or
other default or Event of Default or impair any right consequent thereon.

         Section 4.10   Rights of Holders to Receive Payment.

         Notwithstanding any other provision of this Indenture (including,
without limitation, Section 4.6 hereof), the right of any Holder to receive, and
to institute suit to enforce, payment of the principal and Change of Control
purchase price of, and premium, if any, and interest on the Securities on or
after the respective due dates expressed in such Securities (including upon
redemption and acceleration of the maturity of the principal of and premium, if
any, and interest on the Securities), shall not be affected or impaired, and
shall be absolute and unconditional.

                                       27
<PAGE>   35

                                    ARTICLE V
                             CONCERNING THE TRUSTEE

         Section 5.1    Duties and Responsibilities of the Trustee; During
                        Default; Prior to Default.

         The Trustee, prior to the occurrence of an Event of Default and after
the curing or waiving of all Events of Default that may have occurred,
undertakes to perform only such duties as are specifically set forth in this
Indenture. In case an Event of Default has occurred (which has not been cured or
waived) 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 or her own affairs.

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

         (a)  prior to the occurrence of an Event of Default and after the
curing or waiving of all such Events of Default that may have occurred:

              (i)  the duties and obligations of the Trustee shall be determined
solely by the express provisions of this Indenture, and the Trustee shall not be
liable except for the performance of such duties and obligations as are
specifically set forth in this Indenture, and no implied covenants or
obligations shall be read into this Indenture against the Trustee; and

              (ii) in the absence of bad faith on the part of the Trustee, the
Trustee may conclusively rely, as to the truth of the statements and the
correctness of the opinions expressed therein, upon any statements, certificates
or opinions furnished to the Trustee and conforming to the requirements of this
Indenture; but in the case of any such statements, certificates or opinions
which by any provision hereof are specifically required to be furnished to the
Trustee, the Trustee shall be under a duty to examine the same to determine
whether or not they conform to the requirements of this Indenture (but need not
confirm or investigate the accuracy of mathematical calculations or other facts
stated therein);

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

         (c)  the Trustee shall not be liable with respect to any action taken
or omitted to be taken by it in good faith in accordance with the direction
received by it pursuant to Section 4.8 hereof; and

         (d)  Whether or not therein expressly so provided, every provision of
this Indenture relating to the conduct or affecting the liability of or
affording protection to the Trustee shall be subject to the provisions of this
Section.

                                       28

<PAGE>   36

         None of the provisions contained in this Indenture shall require the
Trustee to expend or risk its own funds or otherwise incur personal financial
liability in the performance of any of its duties or in the exercise of any of
its rights or powers, if there shall be reasonable ground for believing that the
repayment of such funds or adequate indemnity against such liability is not
reasonably assured to it.

         Section 5.2    Certain Rights of the Trustee.

         Subject to Section 5.1 hereof:

         (a)  the Trustee may conclusively rely and shall be protected in acting
or refraining from acting upon any resolution, Officers' Certificate or any
other certificate (including, without limitation, any certificate provided to
the Trustee pursuant to Section 3.5 hereof), statement, instrument, opinion,
report, notice, request, consent, order, bond, debenture, note, coupon, security
or other paper document believed by it to be genuine and to have been signed or
presented by the proper party or parties;

         (b)  any request, direction, order or demand of the Issuer mentioned
herein shall be sufficiently evidenced by an Officers' Certificate (unless other
evidence in respect thereof be herein specifically prescribed) and any
resolution of the Board of Directors may be evidenced to the Trustee by a copy
thereof certified by the Secretary or an Assistant Secretary of the Issuer;

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

         (d)  the Trustee shall be under no obligation to exercise any of the
trusts or powers vested in it by this Indenture at the request, order or
direction of any of the Securityholders pursuant to the provisions of this
Indenture, unless such Securityholders shall have offered to the Trustee
security or indemnity reasonably satisfactory to it against the costs, expenses
and liabilities that might be incurred therein or thereby;

         (e)  the Trustee shall not be liable for any action taken or omitted by
it in good faith and believed by it to be authorized or within the discretion,
rights or powers conferred upon it by this Indenture;

         (f)  the Trustee shall not be bound to make any investigation into the
facts or matters stated in any resolution, certificate, statement, instrument,
opinion, report, notice, request, consent, order, approval, appraisal, bond,
debenture, note, coupon, security, or other paper or document, in each case
relating to a Series of Securities, unless requested in writing so to do by the
Holders of not less than a majority in aggregate principal amount of the
Securities of such Series then Outstanding; provided that, if the payment within
a reasonable time to the Trustee of the costs, expenses or liabilities likely to
be incurred by it in the making of such investigation is, in the opinion of the
Trustee, not reasonably assured by the security afforded to it by the terms of
this Indenture, the Trustee may require reasonable indemnity against such
expenses or liabilities

                                       29

<PAGE>   37

as a condition to proceeding; the reasonable expenses of every such examination
shall be paid by the Issuer, or by the Trustee or any predecessor Trustee and
repaid by the Issuer upon demand;

         (g)  the Trustee shall not be bound to make any investigation into the
facts or matters stated in any resolution, certificate, statement, instrument,
opinion, report, notice, request, direction, consent, order, bond, debenture,
note, other evidence of indebtedness or other paper or document, but the
Trustee, in its discretion, may make such further inquiry or investigation into
such facts or matters as it may see fit, and, if the Trustee shall determine to
make such further inquiry or investigation, it shall be entitled to examine the
books, records and premises of the Issuer, personally or by agent or attorney at
the sole cost of the Issuer and shall incur no liability or additional liability
of any kind by reason of such inquiry or investigation;

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

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

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

         (k)  the Trustee may request that the Company deliver an Officers'
Certificate setting forth the names of individuals and/or titles of officers
authorized at such time to take specified actions pursuant to this Indenture,
which Officers' Certificate may be signed by any person authorized to sign an
Officers' Certificate, including any person specified as so authorized in any
such certificate previously delivered and not superseded.

         Section 5.3    Trustee Not Responsible for Recitals, Disposition of
                        Securities or Application  of Proceeds Thereof.

         The recitals contained herein and in the Securities, except the
Trustee's certificate of authentication, shall be taken as the statements of the
Issuer, and the Trustee assumes no responsibility for the correctness of the
same. The Trustee makes no representation as to the validity or sufficiency of
this Indenture or of the Securities. The Trustee shall not be accountable for
the use or application by the Issuer or any of the Securities or of the proceeds
thereof.

         Section 5.4    Trustee and Agents May Hold Securities; Collections,
                        etc.

         The Trustee or any agent of the Issuer or the Trustee, in its
individual or any other capacity, may become the owner or pledgee of Securities
with the same rights it would have if it were not the Trustee or such agent and
may otherwise deal with the Issuer and receive, collect,

                                       30

<PAGE>   38

hold and retain collections from the Issuer with the same rights it would have
if it were not the Trustee or such agent.

         Section 5.5    Moneys Held by Trustee.

         Subject to the provisions of Section 9.4 hereof, all moneys received by
the Trustee shall, until used or applied as herein provided, be held in trust
for the purposes for which they were received, but need not be segregated from
other funds except to the extent required by mandatory provisions of law.
Neither the Trustee nor any agent of the Issuer or the Trustee shall be under
any liability for interest on any moneys received by it hereunder, except as the
Issuer and the Trustee otherwise may agree.

         Section 5.6    Compensation and Indemnification of Trustee and Its
                        Prior Claim.

         The Issuer covenants and agrees to pay to the Trustee from time to time
as shall be agreed upon between the Issuer and the Trustee in writing from time
to time, and the Trustee shall be entitled to compensation (which shall not be
limited by any provision of law relating to the compensation of a trustee of an
express trust), and the Issuer covenants and agrees to pay or reimburse the
Trustee and each predecessor Trustee and their agents upon its request for all
reasonable expenses, disbursements and advances incurred or made by or on behalf
of it in accordance with any of the provisions of this Indenture (including the
reasonable compensation and expenses and disbursements of its counsel and of all
agents and other persons not regularly in its employ), except to the extent any
such expense, disbursement or advance may arise from the Trustee's gross
negligence or willful misconduct. The Issuer also covenants to indemnify the
Trustee and each predecessor Trustee and their agents for, and to hold it
harmless against, any and all loss, liability, damage, claims or expense arising
out of or in connection with the acceptance or administration of this Indenture
or the trusts hereunder and its duties hereunder and the performance of its
duties hereunder, including the costs and expenses of defending and
investigating any claim of liability in the premises, except to the extent any
such loss, liability or expense is due to its own gross negligence or willful
misconduct. The obligations of the Issuer under this Section 5.6 to compensate
and indemnify the Trustee and each predecessor Trustee and to pay or reimburse
the Trustee and each predecessor Trustee for expenses, disbursements and
advances shall constitute additional indebtedness hereunder and shall survive
the satisfaction and discharge of this Indenture.

         The Trustee shall have a lien prior to the Securities as to all
property and funds held by it hereunder for any amount owing it or any
predecessor Trustee pursuant to this Section 5.6, except with respect to funds
held in trust for the benefit of the Holders of particular Securities.

         When the Trustee incurs expenses or renders services in connection with
an Event of Default, the expenses (including the reasonable charges and expenses
of its counsel) and the compensation for the services are intended to constitute
expenses of administration under any applicable federal or state bankruptcy,
insolvency or other similar law.

         The provisions of this Section shall survive the termination of this
Indenture.

                                       31

<PAGE>   39

         Section 5.7    Right of Trustee to Rely on Officers' Certificate, etc.

         Subject to Section 5.1 and Section 5.2 hereof, whenever in the
administration of the trusts of this Indenture the Trustee shall deem it
necessary or desirable that a matter be proved or established prior to taking or
suffering or omitting any action hereunder, such matter (unless other evidence
in respect thereof be herein specifically prescribed) may, in the absence of
negligence or bad faith on the part of the Trustee, be deemed to be conclusively
proved and established by an Officers' Certificate delivered to the Trustee.

         Section 5.8    Persons Eligible for Appointment as Trustee.

         The Trustee hereunder shall at all times be a corporation organized and
doing business under the laws of the United States or of a state thereof, having
a combined capital and surplus of at least $50,000,000, and which is authorized
under such laws to exercise corporate trust powers and subject to supervision or
examination by federal or state authority. If such corporation publishes reports
of condition at least annually, pursuant to law or to the requirements of a
federal, state or District of Columbia supervising or examining authority, then
for the purposes of this Section 5.8, the combined capital and surplus of such
corporation shall be deemed to be its combined capital and surplus as set forth
in its most recent report of condition so published. No obligor on the
Securities or Person directly or indirectly controlling, controlled by or under
common control with such obligor shall serve as Trustee.

         Section 5.9    Resignation and Removal; Appointment of Successor
                        Trustee.

         (a)  The Trustee may at any time resign by giving written notice of
resignation to the Issuer and by mailing notice thereof by first-class mail to
Holders of Securities at their last addresses as they shall appear on the
Securities Register. Upon receiving such notice of resignation, the Issuer shall
promptly appoint a successor trustee by written instrument in duplicate,
executed by authority of the Board of Directors, one copy of which instrument
shall be delivered to the resigning Trustee and one copy to the successor
Trustee. If no such successor trustee shall have been so appointed and have
accepted appointment within 30 days after the mailing of such notice of
resignation, the resigning Trustee may petition any court of competent
jurisdiction for the appointment of a successor trustee, or any Securityholder
who has been a bona fide Holder of a Security or Securities for at least six
months may, on behalf of himself and all others similarly situated, petition any
such court for the appointment of a successor trustee. Such court may thereupon,
after such notice, if any, as it may deemed proper and prescribe, appoint a
successor trustee.

         (b)  In case at any time any of the following shall occur:

              (i)   the Trustee shall fail to comply with the provisions of
Section 310(b) of the Trustee Indenture Act, after written request thereafter by
the Issuer or by any Securityholder who has been a bona fide Holder of a
Security or Securities for at least six months;

              (ii)  the Trustee shall cease to be eligible in accordance with
the provisions of Section 5.8 hereof and shall fail to resign after written
request therefor by the Issuer or by any such Securityholder; or

                                       32
<PAGE>   40

              (iii) the Trustee shall become incapable of acting, or shall be
adjudged a bankrupt or insolvent, or a receiver or liquidator of the Trustee or
of its property shall be appointed, or any public officer shall take charge or
control of the Trustee or of its property or affairs for the purpose of
rehabilitation, conservation or liquidation;

then, in any such case, the Issuer may remove the Trustee and appoint a
successor trustee by written instrument, in duplicate, executed by order of the
Board of Directors of the Issuer, one copy of which instrument shall be
delivered to the Trustee so removed and one copy of which shall be delivered to
the successor trustee, or, any Securityholder who has been a bona fide Holder of
a Security or Securities for at least six months may on behalf of himself and
all others similarly situated, petition any court of competent jurisdiction for
the removal of the Trustee and the appointment of a successor trustee. Such
court may thereupon, after such notice, if any, as it may deem proper and
prescribe, remove the Trustee and appoint a successor trustee.

         (c)  The Holders of a majority in aggregated principal amount of the
Securities at the time Outstanding may at any time remove the Trustee and
appoint a successor trustee by delivering to the Trustee so removed, to the
successor trustee so appointed and to the Issuer the evidence provided for in
Section 6.1 hereof of the action in that regard taken by the Securityholders.

         (d)  Any resignation or removal of the Trustee and any appointment of a
successor trustee pursuant to any of the provisions of this Section 5.9 shall
become effective only upon acceptance of appointment by the successor trustee as
provided in Section 5.10 hereof.

         Section 5.10   Acceptance of Appointment by Successor Trustee.

         Any successor trustee appointed as provided in Section 5.9 hereof shall
execute and deliver to the Issuer and to its predecessor Trustee an instrument
accepting such appointment hereunder, and thereupon the resignation or removal
of the predecessor Trustee shall become effective and such successor trustee,
without any further act, deed or conveyance, shall become vested with all
rights, powers, duties and obligations of its predecessor hereunder, with like
effect as if originally named as trustee herein; but, nevertheless, on the
written request of the Issuer or of the successor trustee, upon payment of its
charges then unpaid, the Trustee ceasing to act shall, subject to Section 9.4
hereof, pay over the successor trustee all moneys at the time held by it
hereunder and shall execute and deliver an instrument transferring to such
successor trustee all such rights, powers, duties and obligations. Upon request
of any such successor trustee, the Issuer shall execute appropriate instruments
in writing for more fully and certainly vesting in and confirming to such
successor such rights and powers. Any Trustee ceasing to act shall,
nevertheless, retain a prior claim upon all property or funds held or collected
by such Trustee to secure any amounts then due it pursuant to the provisions of
Section 5.6 hereof.

         Upon acceptance of appointment by a successor trustee as provided in
this Section 5.10, the Issuer shall mail notice thereof by first-class mail to
the Holders of Securities at their last addresses as they shall appear in the
Securities Register. If the acceptance of appointment is substantially
contemporaneous with the resignation then the notice called for by the preceding
sentence may be combined with the notice called for by Section 5.9 hereof. If
the Issuer fails to

                                       33
<PAGE>   41

mail such notice within 10 days after acceptance of appointment by the successor
trustee, the successor trustee shall cause such notice to be mailed at the
expense of the Issuer.

         Notwithstanding replacement of the Trustee pursuant to this Section
5.10, the Issuer's obligations under Section 5.6 hereof shall continue for the
benefit of the retiring Trustee.

         Section 5.11   Merger, Conversion, Consolidation or Succession to
                        Business of Trustee.

         Any corporation into which the Trustee may be merged or converted or
with which it may be consolidated, or any corporation resulting from any merger,
conversion or consolidation to which the Trustee shall be a party, or any
corporation succeeding to all or substantially all of the corporate trust
business of the Trustee, shall be the successor of the Trustee hereunder,
provided that such corporation shall be eligible under the provisions of Section
5.8 hereof, without the execution or filing of any paper or any further act on
the part of any of the parties hereto, anything herein to the contrary
notwithstanding.

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

                                   ARTICLE VI
                         CONCERNING THE SECURITYHOLDERS

         Section 6.1    Evidence of Action Taken by Securityholders.

         Any request, demand, authorization, direction, notice, consent, waiver
or other action provided by this Indenture to be given or taken by
Securityholders may be embodied in and evidenced by one or more instruments of
substantially similar tenor signed by such Securityholders, in person or by
agent duly appointed in writing; and, except as herein otherwise expressly
provided, such action shall become effective when such instrument or instruments
are received by a Responsible Officer of the Trustee. Proof of execution of any
instrument or of a writing appointing any such agent shall be sufficient for any
purpose of this Indenture and (subject to Section 5.1 and Section 5.2 hereof)
conclusive in favor of the Trustee and the Issuer, if made in the manner
provided in this Article.

                                       34

<PAGE>   42

         Section 6.2    Proof of Execution of Instruments and of Holding of
                        Securities Record Date.

         Subject to Section 5.1 and Section 5.2 hereof, the execution of any
instrument by a Securityholder or his agent or proxy may be provided in
accordance with such reasonable rules and regulations as may be prescribed by
the Trustee or in such manner as shall be satisfactory to the Trustee. The
holding of Securities shall be provided by the Securities Register or by a
certificate of the Security Registrar thereof. The Issuer may set a record date
for purposes of determining the identity of Holders of Securities entitled to
vote or consent to any action referred to in Section 6.1 hereof, which record
date may be set at any time or from time to time by written notice to the
Trustee for any date or dates (in the case of any adjournment or resolicitation)
not more than 60 days nor less than five days prior to the proposed date of such
vote or consent, and thereafter, notwithstanding any other provisions hereof,
only Holders of Securities of record on such record date shall be entitled to so
vote or give such consent or to withdraw such vote or consent.

         Section 6.3    Holders to be Treated as Owners.

         The Issuer, the Trustee and any agent of the Issuer or the Trustee may
deem and treat the Person in whose name any Security shall be registered upon
the Securities Register as the absolute owner of such Security (whether or not
such Security shall be overdue and notwithstanding any notation of ownership or
other writing thereon) for the purpose of receiving payment of or on account of
the principal and Change of Control purchase price of, and premium, if any, on
and, subject to the provisions of this Indenture, interest on such Security and
for all other purposes; and neither the Issuer nor the Trustee nor any agent of
the Issuer or the Trustee shall be affected by any notice to the contrary. All
such payments so made to any such Person, or upon his order, shall be valid and
to the extent of the sum or sums so paid, effectual to satisfy and discharge the
liability for moneys payable upon any such Security.

         Section 6.4    Securities Owned by Issuer Deemed Not Outstanding.

         In determining whether the Holders of the requisite aggregate principal
amount of Securities have concurred in any direction, consent or waiver under
this Indenture, Securities that are owned by the Issuer or any other obligor on
the Securities or by any Person directly or indirectly controlling or controlled
by or under direct or indirect common control with the obligor on the Securities
shall be disregarded and deemed not to be Outstanding for the purpose of any
such determination, except that for the purpose of determining whether the
Trustee shall be protected in relying on any such direction, consent or waiver
only Securities that a Responsible Officer of the Trustee actually knows are so
owned shall be so disregarded. Securities so owned that have been pledged in
good faith may be regarded as Outstanding if the pledgee establishes to the
satisfaction of the Trustee the pledgee's right so to act with respect to such
Securities and that the pledgee is not the Issuer or any other obligor upon the
Securities or any Person directly or indirectly controlling or controlled by or
under direct or indirect common control with the Issuer or any other obligor on
the Securities. In case of a dispute as to such right, the advice of counsel
shall be full protection in respect of any decision made by the Trustee in
accordance with such advice. Upon request of the Trustee, the Issuer shall
furnish to the Trustee promptly an Officers' Certificate listing and identifying
all Securities, if any, known by

                                       35

<PAGE>   43

the Issuer to be owned or held by or for the account of any of the
above-described Persons; and, subject to Section 5.1 and Section 5.2 hereof, the
Trustee shall be entitled to accept such Officers' Certificate as conclusive
evidence of the facts therein set forth and of the facts therein set forth and
of the fact that all Securities not listed therein are Outstanding for the
purpose of any such determination.

         Section 6.5    Right of Revocation of Action Taken.

         At any time prior to (but not after) the evidencing to the Trustee, as
provided in Section 6.1 hereof, of the taking of any action by the Holders of
the percentage in aggregate principal amount of the Securities of a Series
specified in this Indenture in connection with such action, any Holder of a
Security the serial number of which is shown by the evidence to be included
among the serial numbers of the Securities, the Holders of which have consented
to such action may, by filing written notice at the Corporate Trust Office and
upon proof of holding as provided in this Article, revoke such action so far as
concerns such Security. Except as aforesaid any such action taken by the Holder
of any Security shall be conclusive and binding upon such Holder and upon all
future Holders and owners of such Security and of any Securities issued in
exchange or substitution therefor, irrespective of whether or not any notation
in regard thereto is made upon any such Security. Any action taken by the
Holders of the percentage in aggregate principal amount of the Securities of a
Series specified in this Indenture in connection with such action shall be
conclusively binding upon the Issuer, the Trustee and the Holders of all such
Securities.

                                   ARTICLE VII
                             SUPPLEMENTAL INDENTURES

         Section 7.1    Supplemental Indentures Without Consent of
                        Securityholders.

         The Issuer, when authorized by a resolution of its Board of Directors,
and the Trustee may from time to time and at any time enter into an indenture or
indentures supplemental hereto for one or more of the following purposes:

         (a)  to convey, transfer, assign, mortgage or pledge to the Trustee as
security for the Securities any property or assets;

         (b)  to evidence the succession of another corporation to the Issuer,
or successive successions, and the assumption by the successor corporation of
the covenants, agreements and obligations of the Issuer pursuant to Article
Eight hereof;

         (c)  to add to the covenants of the Issuer such further covenants,
restrictions, conditions or provisions as the Board of Directors shall consider
to be for the protection of the Holders of Securities, and to make the
occurrence, or the occurrence and continuance of a default in any such
additional covenants, restrictions, conditions or provisions an Event of Default
permitting the enforcement of all or any of the several remedies provided in
this Indenture as herein set forth; provided, that in respect of any such
additional covenant, restriction, condition or provision such supplemental
indenture may provide for a particular period of grace after default (which
period may be shorter or longer than that allowed in the case of other defaults)
or

                                       36

<PAGE>   44

may provide for immediate enforcement upon such an Event of Default or may limit
the remedies available to the Trustee due solely to such an Event of Default or
may limit the right of the Holders of a majority in aggregate principal amount
of the Securities to waive such an Event of Default;

         (d)  to cure any ambiguity, omission, defect or inconsistency contained
herein or in the Securities, or to make such other provisions in regard to
matters or questions arising under this Indenture or under any supplemental
indenture as the Board of Directors may deem necessary or desirable; provided,
however, that the Trustee and the Issuer shall determine such cure or other
provisions shall not adversely affect the interests of the Holders of the
Securities of any Series then Outstanding in any material respect;

         (e)  to make any other change that does not adversely affect the
interests of the Holders of the Securities of any Series then Outstanding in any
material respect;

         (f)  to provide for uncertificated Securities in addition to or in
place of certificated Securities;

         (g)  to modify or supplement this Indenture or any indenture
supplemental hereto in such manner as to permit the qualification thereof under
the Trust Indenture Act of any other similar federal statute hereafter in
effect;

         (h)  to establish the form or terms of a Series of Securities as
permitted by Section 2.01; and

         (i)  to provide that specific provisions of this Indenture shall not
apply to a Series of Securities not previously issued.

         The Trustee is hereby authorized to join in the execution of any such
supplemental Indenture, to make any further appropriate agreements and
stipulations that may be therein continued and to accept the conveyance,
transfer, assignment, mortgage or pledge of any property thereunder, but the
Trustee shall not be obligated to enter into any such supplemental indenture
that affects the Trustee's own rights, duties or immunities under this Indenture
or otherwise.

         Any supplemental indenture authorized by the provisions of this Section
7.1 may be executed without the consent of the Holders of any of the Securities
at the time Outstanding, notwithstanding any of the provisions of Section 7.2
hereof.

         Section 7.2    Supplemental Indentures With Consent of Securityholders.

         With the consent (evidenced as provided in Article Six hereof) of the
Holders of not less than a majority in aggregate principal amount of the
Securities of each Series affected by a proposed amendment at the time
Outstanding, the Issuer, when authorized by a resolution of its Board of
Directors, and the Trustee may, from time to time and at any time, modify this
Indenture or any indentures supplemental hereto or the rights of the Holders of
the Securities of each such Series; provided, that no such supplemental
indenture shall (a) change the Stated

                                       37

<PAGE>   45

Maturity of the principal of, or any installment of principal of or interest on,
any Security, or reduce the principal amount thereof, or reduce the rate or
extend the time of payment of interest thereon, or reduce any amount payable on
redemption thereof or upon a Change of Control or impair or affect the right of
any Securityholder to institute suit for the payment thereof or make any change
to Section 3.9 hereof that adversely affects the rights of the Holders of the
Securities, in each case without the consent of the Holder of each Security so
affected, or (b) without the consent of the Holders of all Securities of each
affected Series then Outstanding, (i) reduce the aforesaid percentage of
Securities, the consent of the Holders of which is required for any such
modification, or the percentage of Securities, the consent of the Holders of
which is required for any waiver provided for in this Indenture, (ii) change any
obligation of the Issuer to maintain an office or agency in the places and for
the purposes specified in Section 3.2 or (iii) make any change in Section 4.9 or
this Section 7.2, except to increase any percentages or to provide that certain
other provisions of this Indenture cannot be modified or waived without the
consent of the Holders of each Outstanding Security affected thereby.

         Upon the request of the Issuer, accompanied by a copy of a resolution
of the Board of Directors certified by the Secretary or an Assistant Secretary
of the Issuer authorizing the execution of any such supplemental indenture, and
upon the filing with the Trustee of evidence of the consent of Securityholders
and other documents, if any, required by Section 6.1 hereof the Trustee shall
join with the Issuer in the execution of such supplemental indenture unless such
supplemental indenture affects the Trustee's own rights, duties or immunities
under this Indenture or otherwise, in which case the Trustee may in its
discretion, but shall not be obligated to enter into such supplemental
indenture.

         It shall not be necessary for the consent of the Securityholders under
this Section 7.2 to approve the particular form of any proposed supplemental
indenture, but it shall be sufficient if such consent shall approve the
substance thereof.

         Promptly after the execution by the Issuer and the Trustee of any
supplemental indenture pursuant to the provisions of this Section 7.2, the
Issuer shall mail a notice thereof by first-class mail to the Holders of
Securities at their addresses as they shall appear on the Securities Register,
setting forth in general terms the substance of such supplemental indenture. Any
failure of the Issuer to mail such notice, or any defect therein, shall not,
however, in any way impair or affect the validity of any such supplemental
indenture.

         Section 7.3    Effect of Supplemental Indenture

         Upon the execution of any supplemental indenture pursuant to the
provisions hereof, this Indenture shall be and be deemed to be modified and
amended in accordance therewith and the respective rights, limitations of
rights, obligations, duties and immunities under this Indenture of the Trustee,
the Issuer and the Holders of Securities shall thereafter be determined,
exercised and enforced hereunder subject in all respects to such modifications
and amendments, and all the terms and conditions of any such supplemental
indenture shall be and be deemed to be part of the terms and conditions of this
Indenture for any and all purposes.

                                       38

<PAGE>   46

         Section 7.4    Documents to be Given to Trustee.

         The Trustee, subject to the provisions of Section 5.1 and Section 5.2
hereof, shall be entitled to receive and shall be fully protected in relying
upon an Officers' Certificate and an Opinion of Counsel as conclusive evidence
that any such supplemental indenture complies with the applicable provisions of
this Indenture.

         Section 7.5    Notation of Securities in Respect of Supplemental
                        Indentures.

         Securities authenticated and delivered after the execution of any
supplemental indenture pursuant to the provisions of this Article Seven may bear
a notation in form approved by the Trustee as to any matters provided for by
such supplemental indenture or as to any action taken at any such meeting by the
Issuer or the Trustee shall so determine, new Securities so modified as to
conform, in the opinion of the Issuer and the Board of Directors, to any
modification of this Indenture contained in any such supplemental indenture may
be prepared by the Issuer, authenticated by the Trustee and delivered in
exchange for the Securities then Outstanding.

                                  ARTICLE VIII
                     CONSOLIDATE, MERGER, SALE OR CONVEYANCE

         Section 8.1    Covenant Not to Merge, Consolidate, Sell or Transfer
                        Assets Except Under Certain Conditions.

         (a)  The Issuer shall not consolidate with or merge into any other
Person, or sell, convey, transfer or lease its properties and assets
substantially as an entirety to any Person, and Issuer shall not permit any
Person to consolidate with or merge into the Issuer, unless: (i) immediately
prior to and immediately following such consolidation, merger, sale or lease, no
Event of Default shall have occurred and be continuing and (ii) the Issuer is
the surviving or continuing corporation, or the surviving or continuing
corporation or corporation that acquires by sale, conveyance, transfer or lease
is incorporated in the United States of America or Canada and expressly assumes
the payment and performance of all obligations of the Issuer under the Indenture
and the Securities.

         (b)  Except for the sale of the properties and assets of the Issuer
substantially as an entirety pursuant to subsection (a) above, and other than
assets required to be sold to conform with governmental regulations, the Issuer
shall not sell or otherwise dispose of any assets (other than short-term,
readily marketable investments purchased for cash management purposes with funds
not representing the proceeds of other asset sales) if on a pro forma basis, the
aggregate net book value of all such sales during the most recent 12-month
period would exceed 10 percent of Consolidated Net Tangible Assets computed as
of the end of the most recent fiscal quarter preceding such sale; provided,
however, that any such sales shall be disregarded for purposes of this 10
percent limitation if the proceeds are invested in assets in similar or related
lines of business of the Issuer and, provided further, that the Issuer may sell
or otherwise dispose of assets in excess of such 10 percent if the proceeds from
such sales or dispositions, which are not reinvested as provided above, are
retained by the Issuer as cash or cash equivalents or are used by the Issuer to
purchase Securities of any Series that are then delivered to the Trustee for

                                       39
<PAGE>   47

cancellation or are used to reduce or retire Indebtedness ranking pari passu in
right of payment to the Securities.

         Section 8.2    Successor Corporation Substituted.

         In case of any such consolidation, merger, sale or transfer, and
following such an assumption by the successor corporation, such successor
corporation shall succeed to and be substituted for the Issuer, with the same
effect as if it had been named herein.

         Such successor corporation may cause to be signed, and may issue either
in its own name or in the name of the Issuer prior to such succession any or all
of the Securities issuable hereunder that theretofore shall not have been signed
by the Issuer and delivered to the Trustee; and, upon the order of such
successor corporation, instead of the Issuer, and subject to all the terms,
conditions and limitations in this Indenture prescribed, the Trustee shall
authenticate and shall deliver any Securities that previously shall have been
signed and delivered by the officers of the Issuer to the Trustee for
authentication and any Securities that such successor corporation thereafter
shall cause to be signed and delivered to the Trustee for that purpose. All of
the Securities so issued shall in all respects have the same legal rank and
benefit under this Indenture as the Securities theretofore or thereafter issued
in accordance with the terms of this Indenture as though all of such Securities
had been issued at the date of the execution hereof.

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

         In the event of any such sale or transfer (other than a transfer by way
of lease) the Issuer or any successor corporation which shall theretofore have
become such in the manner described in this Article 8 shall be discharged from
all obligations and covenants under this Indenture and the Securities and may be
liquidated and dissolved.

         Section 8.3    Opinion of Counsel to Trustee; Officers' Certificate.

         The Trustee, subject to the provisions of Section 5.1 and Section 5.2
hereof, shall receive an Officers' Certificate and an Opinion of Counsel as
conclusive evidence that any such consolidation, merger, sale or transfer, and
any such assumption, and any such liquidation or dissolution, complies with the
applicable provisions of this Indenture.

                                   ARTICLE IX
                           SATISFACTION AND DISCHARGE
                         OF INDENTURE; UNCLAIMED MONEYS

         Section 9.1    Satisfaction and Discharge of Indenture.

         If at any time (a) the Issuer shall have paid or caused to be paid the
principal and Change of Control purchase price of and premium, if any, and
interest on all the Securities Outstanding hereunder, as and when the same shall
have become due and payable, or (b) the Issuer shall have delivered to the
Trustee for cancellation of all Securities theretofore authenticated (other than

                                       40

<PAGE>   48

any Securities which shall have been destroyed, lost or stolen and which shall
have been replaced or paid as provided in Section 2.7 hereof) or (c)(i) all such
Securities not theretofore delivered to the Trustee for cancellation shall have
become due and payable, or are by their terms to become due and payable within
one year or are to be called for redemption under arrangements satisfactory to
the Trustee for the giving of notice of redemption, and (ii) the Issuer shall
have irrevocably deposited or caused to be deposited with the Trustee as trust
funds the entire amount in cash (other than moneys repaid by the Trustee or any
paying agent to the Issuer in accordance with Section 9.4 hereof) or U.S.
Government Obligations, maturing as to principal, premium, if any, and interest
in such amounts and at such times as will insure (without reinvestment) the
liability of cash 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 at maturity all such Securities not theretofore
delivered to the Trustee for cancellation, including principal, premium, if any,
and interest due or to become due to such date of maturity as the case may be,
and if, in any such case, the Issuer shall also pay or cause to be paid all
other sums payable hereunder by the Issuer, then this Indenture shall cease to
be of further effect (except as to (i) rights of registration of transfer and
exchange, and the Issuer's right to optional redemption, (ii) substitution of
apparently mutilated, defaced, destroyed, lost or stolen Securities, (iii)
rights of Holders to receive payments of principal thereof (including any Change
of Control purchase price previously accrued) and premium, if any, and interest
thereon, upon the original stated due dates therefor (but not upon
acceleration), (iv) the rights and obligations and immunities of the Trustee
hereunder and (v) the rights of the Securityholders as beneficiaries hereof with
respect to the property so deposited with the Trustee payable to all or any of
them), and the Trustee, on demand of the Issuer accompanied by an Officers'
Certificate and an Opinion of Counsel and at the cost and expense of the Issuer,
shall execute proper instruments acknowledging such satisfaction of and
discharging this Indenture; provided that the rights of Holders of the
Securities to receive amounts in respect of principal of and premium, if any,
and interest or the Securities held by them shall not be delayed longer than
required by then applicable mandatory rules or policies of any securities
exchange upon which the Securities are listed.

         The Issuer agrees to reimburse the Trustee for any costs or expenses
thereafter reasonably and properly incurred and to compensate the Trustee for
any services thereafter reasonably and properly rendered by the Trustee in
connection with this Indenture or the Securities.

         Section 9.2    Application by Trustee of Funds Deposited for Payment of
                        Securities.

         Subject to Section 9.4 hereof, all moneys deposited with the Trustee
pursuant to Section 9.1 hereof shall be held in trust and applied, by it to the
payment, either directly or through any paying agent (including the Issuer
acting as its own paying agent), to the Holders of the particular Securities for
the payment or redemption of which such moneys have been deposited with the
Trustee, of all sums due and to become due thereon for principal and Change of
Control purchase price, premium, if any, and interest; but such money need not
be segregated from other funds except to the extent required by law.

                                       41
<PAGE>   49

         Section 9.3    Repayment of Moneys Held by Paying Agent.

         In connection with the satisfaction and discharge of this Indenture all
moneys then held by any paying agent under the provisions of this Indenture
shall, upon written demand of the Issuer, be repaid to it or paid to the Trustee
and thereupon such paying agent shall be released from all further liability
with respect to such moneys.

         Section 9.4    Return of Moneys Held by Trustee and Paying Agent
                        Unclaimed for Two Years.

         Any moneys deposited with or paid to the Trustee or any paying agent
for the payment of the principal or Change of Control purchase price of or
premium or interest on any Security and not applied but remaining unclaimed for
two years after the date upon which such principal, Change of Control purchase
price, premium or interest shall have become due and payable shall, upon the
written request of the Issuer, be repaid to the Issuer by the Trustee or such
paying agent, and the Holder of such Security shall, unless otherwise required
by mandatory provisions of applicable escheat or abandoned or unclaimed property
laws, thereafter look only to the issuer for any payment which such Holder may
be entitled to collect, and all liability of the Trustee or any paying agent
with respect to such moneys shall thereupon cease.

         Section 9.5    Defeasance and Discharge of Indenture

         The Issuer will be deemed to have paid and will be discharged from any
and all obligations in respect of the Securities, on the 123rd day after the
deposit referred to in subparagraph (A) hereof has been made, and the provisions
of this Indenture will no longer be in effect with respect to the Securities
(and the Trustee, at the expense of the Issuer, shall execute proper instruments
acknowledging the same), except as to:

         (a)  rights of registration of transfer and exchange, and the Issuer's
right of optional redemption, (b) substitution of apparently mutilated, defaced,
destroyed, lost or stolen securities, (c) rights of Holders to receive payments
of principal (including rights to receive any Change of Control purchase price
previously accrued) thereof and premium, if any, and interest thereon, (d) the
rights, obligations and immunities of the Trust hereunder, (e) the rights of the
Securityholders as beneficiaries hereof with respect to the property so
deposited with the Trustee payable to all or any of them and (f) the obligations
of the Issuer to maintain a place of payment for the Securities under Section
3.1 hereof; provided that the following conditions shall have been satisfied:

              (i)   with reference to this Section 9.5 the Issuer has
irrevocably deposited or caused to be irrevocably deposited with the Trustee (or
another trustee satisfying the requirements of Section 5.8 hereof) as trust
funds in trust, specifically pledged as security for, and dedicated solely to,
the benefit of the Holders of the Securities, (i) money in an amount, or (ii)
U.S. Government Obligations which through the payment of interest and principal
in respect thereof in accordance with their terms (without reinvestment) will
provide not later than one day before the due date of any payment referred to in
clause (x) or (y) of this subparagraph (A) money in an amount, or (iii) a
combination thereof, sufficient, in the opinion of a nationally recognized firm
of independent public accountants expressed in a written certification thereof

                                       42

<PAGE>   50

delivered to the Trustee, to pay and discharge, after payment of all federal,
state and local taxes or other charges and assessments in respect thereof
payable by the Trustee, (x) the principal and Change of Control purchase price
of, premium, if any, and each installment of principal and interest on the
Outstanding Securities at the maturity date of such principal or installment of
principal or interest and (y) any mandatory sinking fund payments or analogous
payments applicable to the Securities on the day on which such payments are due
and payable in accordance with the terms of this Indenture and the Securities;

              (ii)  the Issuer has delivered to the Trustee (i) an Opinion of
Counsel to the effect that Holders will not recognize income, gain or loss for
federal income tax purposes as a result of the Issuer's exercise of its option
under this Section 9.5 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, defeasance and discharge had not occurred, which Opinion of
Counsel must be based on (x) a change in applicable federal income tax law or
related Treasury Regulations after the date of this Indenture or (y) a ruling
received by the Issuer from the Internal Revenue Service to the same effect and
(ii) an Opinion of Counsel to the effect that the defeasance trust does not
constitute an "investment company" under the Investment Company Act of 1940, as
amended, and after the passage of 123 days following the deposit, the trust fund
will not be subject to the effect of Section 547 of the U.S. Bankruptcy Code or
Section 15 of the New York Debtor and Creditor Law;

              (iii) immediately after giving effect to such deposit on a pro
forma basis, no Event of Default, or event that after the giving of notice or
lapse of time or both would become an Event of Default, shall have occurred and
be continuing on the date of such deposit or during the period ending on the
123rd day after the date of such deposit, and such deposit shall not result in a
breach or violation of, or constitute a default under, any other agreement or
instrument to which the Issuer is a party or by which the Issuer is bound; and

              (iv)  if at such time the Securities are listed on a national
securities exchange, the Issuer has delivered to the Trustee an Opinion of
Counsel to the effect that the Securities will not be delisted as a result of
such deposit, defeasance and discharge.

         Section 9.6    Defeasance of Certain Obligations.

         The Issuer may omit to comply with any term, provision, or condition
set forth in this Indenture in Sections 3.8 and Section 3.9, and Section 4.l(d)
(with respect to Sections 3.8 and 3.9) and Section 4.1(c) shall be deemed not to
be an Event of Default on the 123rd day after the deposit referred to in
subparagraph (A) hereof if:

         (A) with reference to this Section 9.6, the Issuer has irrevocably
deposited or caused to be irrevocably deposited with the Trustee (or another
trustee satisfying the requirements of Section 5.6 hereof) as trust funds in
trust, specifically pledged as security for, and dedicated solely to, the
benefit of the Holders of the Securities, (i) money in an amount, or (ii) U.S.
Government Obligations which bought the payment of interest and principal in
respect thereof in accordance with their terms (without reinvestment) will
provide not later than one day before the due date of any payment referred to in
clauses (x) or (y) of this Section 9.6, money in an amount, or (iii) a
combination thereof, sufficient, in the opinion of a nationally recognized firm
of

                                       43

<PAGE>   51

independent public accountants expressed in a certification thereof delivered to
the Trustee, to pay and discharge, after payment of all federal, state and local
taxes or other charges and assessments in respect thereof payable by the
Trustee, (x) the principal and Change of Control purchase price of, premium, if
any, and each installment of principal and interest on the Outstanding
Securities at the maturity date of such principal or installment of principal or
interest and (y) any mandatory sinking fund payments or analogous payments
applicable to the Securities on the day on which such payments are due and
payable in accordance with the terms of this Indenture and the Securities;

         (B)  the Issuer has delivered to the Trustee (i) an Opinion of Counsel
to the effect that Holders will not recognize income, gain or loss for federal
income tax purposes as a result of the Issuer's exercise of its option under
this Section 9.6 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, defeasance and discharge had not occurred, and (ii) an Opinion of
Counsel to the effect that the defeasance trust does not constitute an
"investment company" under the Investment Company Act of 1940, as amended, and
after the passage of 123 days following the deposit, the trust fund will not be
subject to the effect of Section 547 of the U.S. Bankruptcy Code or Section 15
of the New York Debtor and Creditor Law;

         (C)  immediately after giving effect to such deposit on a pro forma
basis, no Event of Default, or event that after the giving of notice or lapse of
time or both would become an Event of Default, shall have occurred and be
continuing on the date of such deposit or during the period ending on the 123rd
day after the date of such deposit, and such deposit shall not result in a
breach or violation of or constitute a default under any other agreement or
instrument to which the Issuer is a party or by which the Issuer is bound; and

         (D)  if at such time the Securities are listed on a national securities
exchange, the Issuer has delivered to the Trustee an Opinion of Counsel to the
effect that the Securities will not be delisted as a result of such deposit,
defeasance and discharge.

         The Issuer shall pay and indemnify the Trustee against any tax, fee or
other charge imposed on or assessed against the U.S. Government Obligations
deposited pursuant to Section 9.5 or this Section 9.6 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 X
                            MISCELLANEOUS PROVISIONS

         Section 10.1   Incorporators, Shareholders, Officers and Directors of
                        Issuer Exempt from Individual Liability.

         No recourse under or upon any obligation, covenant or agreement
contained in this Indenture, or in any Security, or because of any indebtedness
evidenced thereby, shall be had against any incorporator, as such, or against
any past, present or future shareholder, officer or director, as such, of the
Issuer or of any successor, either directly or through the Issuer or any
successor, under any rule of law, statute or constitutional provision or by the
enforcement of any

                                       44
<PAGE>   52
assessment or by any legal or equitable proceeding or otherwise, all such
liability being expressly waived and released by the acceptance of the
Securities by the Holders thereof and as part of the consideration for the issue
of the Securities.

         Section 10.2   Provisions of the Indenture for the Sole Benefit of
                        Parties and Securityholders.

         Nothing in this Indenture or in the Securities, expressed or implied,
shall give or be construed to give to any Person, other than the parties hereto
and their successors and the Holders (and, where expressly set forth herein,
owners of interests in any Global Security), any legal or equitable right,
remedy or claim under this Indenture or under any covenant or provision herein
contained, all such covenants and provisions being for the sole benefit of the
parties hereto and their successors and the Holders (and, where expressly set
forth herein, owners of interests in any Global Security).

         Section 10.3   Successors and Assigns of Issuer Bound by Indenture.

         All the covenants, stipulations, promises and agreements in this
Indenture contained by or in behalf of the Issuer shall bind its successors and
assigns, whether so expressed or not.

         Section 10.4   Notices and Demands on Issuer, Trustee and
                        Securityholders.

         Any notice or demand which by any provision of this Indenture is
required or permitted to be given or served by the Trustee or by the Holders to
or on the Issuer may be given or served by being deposited postage prepaid,
first-class mail (except as otherwise specifically provided herein) addressed
(until another address of the Issuer is filed by the Issuer with the Trustee) to
NRG Energy, Inc., 901 Marquette Avenue, Suite 2300, Minneapolis, Minnesota
55402, Attention: Chief Financial Officer. Any notice, direction, request or
demand by the Issuer or any Securityholder to or upon the Trustee shall be in
writing and shall be deemed to have been sufficiently given or made, for all
purposes, if given or made in person or by first-class mail, telecopier or
overnight air courier guaranteeing next day delivery at the Corporate Trust
Office or such office or agency designated for such purpose in Section 3.2
hereof.

         Where this Indenture provides for notice to Holders, such notice shall
be sufficiently given (unless otherwise herein expressly provided) if in writing
and mailed, first-class postage prepaid, to each Holder entitled thereto, at his
last address as it appears in the Securities Register. In any case where notice
to Holders is given by mail, neither the failure to mail such notice, nor any
defect in any notice so mailed, to any particular Holder shall affect the
sufficiency of such notice with respect to other Holders. Where this Indenture
provides for notice in any manner, such notice may be waived in writing by the
Person entitled to receive such notice, either before or after the event, and
such waiver shall be the equivalent of such notice. Waivers of notice by Holders
shall be filed with the Trustee, but such filing shall not be a condition
precedent to the validity of any action taken in reliance upon such waiver.

         In case, by reason of the suspension of or irregularities in regular
mail service, it shall be impracticable to mail notice to the Issuer and
Securityholders when such notice is required to be

                                       45

<PAGE>   53

given pursuant to any provision of this Indenture, then any manner of giving
such notice as shall be satisfactory to the Trustee shall be deemed to be a
sufficient giving of such notice.

         Section 10.5   Officers' Certificates and Opinions of Counsel,
                        Statements to be Contained Therein.

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

         Each certificate or opinion provided for in this Indenture and
delivered to the Trustee with respect to compliance with a condition or covenant
provided for in this Indenture shall include (a) a statement that the Person
making such certificate or opinion has read such covenant or condition, (b) a
brief statement as to the nature and scope of the examination or investigation
upon which the statements or opinions contained in such certificate or opinion
are based, (c) a statement that, in the opinion of such Person, he has made such
examination or investigation as is necessary to enable him to express an
informed opinion as to whether or not such covenant or condition has been
complied with and (d) a statement as to whether or not, in the opinion of such
Person, such condition or covenant has been complied with.

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

         Any certificate, statement or opinion of an officer of the Issuer or of
counsel may be based, insofar as it relates to accounting matters, upon a
certificate or opinion of or representations by an accountant or firm of
accountants in the employ of the Issuer, unless such officer or counsel, as the
case may be, knows that the certificate or opinion or representations with
respect to the accounting matters upon which his certificate, statement or
opinion may be based as aforesaid are erroneous, or in the exercise of
reasonable care should know that the same are erroneous.

         Any certificate or opinion of any independent firm of public
accountants or Investment Banker filed with the Trustee shall contain a
statement that such firm is independent.

                                       46
<PAGE>   54

         Section 10.6   Payments Due on Saturdays, Sundays and Holidays

         If the date of maturity of interest on or principal, Change of Control
purchase price, or premium, if any, of the Securities or the date fixed for
redemption of any Security shall not be a Business Day, then payment of
interest, principal, Change of Control purchase price or premium need not be
made on such date, but may be made on the next succeeding Business Day with the
same force and effect as if made on the date of maturity or the date fixed for
redemption, and no interest shall accrue for the period after such date.

         Section 10.7   New York Law to Govern.

         THIS INDENTURE SHALL, PURSUANT TO SECTION 5-1401 OF THE NEW YORK
GENERAL OBLIGATIONS LAW, BE GOVERNED BY THE LAW OF THE STATE OF NEW YORK,
WITHOUT REFERENCE TO THE CHOICE OF LAW PROVISIONS THEREOF (OTHER THAN SUCH
SECTION 5-1401).

         Section 10.8   Counterparts.

         This Indenture may be executed in any number of counterparts, each of
which shall be an original, but such counterparts shall together constitute but
one and the same agreement.

         Section 10.9   Effect of Headings.

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

                                   ARTICLE XI
                            REDEMPTION OF SECURITIES

         Section 11.1   Right of Optional Redemption Price.

         The Issuer at its option may, at any time, redeem the Securities of a
Series, in whole or in part, upon payment of a redemption price equal to the
greater of (i) the principal amount of the Securities of such Series to be
redeemed plus accrued and unpaid interest thereon, if any, to the date of
redemption, or (ii) the Make Whole Amount plus accrued and unpaid interest, if
any, from the last payment date to the redemption date.

         Section 11.2   Notice of Redemption.

         Notice of redemption to the Holders of Securities to be redeemed shall
be given by the Issuer by mailing notice of such redemption by first class mail,
postage prepaid, at least 30 days and not more than 60 days prior to the date
fixed for redemption to such Holders of Securities at their last addresses as
they shall appear in the Securities Register. Failure to give 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.

         The notice of redemption to each Holder shall specify that the
Securities are being redeemed pursuant to this Article 11, the date fixed for
redemption, the place or places of

                                       47

<PAGE>   55

payment, the CUSIP and ISIN numbers (as applicable), that payment will be made
upon presentation and surrender of the Securities, that interest accrued to the
date fixed for redemption will be paid as specified in this Article and that, on
and after said date interest thereon or on the portions thereof to be redeemed
will cease to accrue.

         The notice of redemption of Securities to be redeemed at the option of
the Issuer shall be given by the Issuer or, at the Issuer's request, by the
Trustee in the name and at the expense of the Issuer, provided that the Issuer
makes such request at least 15 days (unless a shorter period shall be acceptable
to the Trustee) prior to the date such notice of redemption must be mailed.

         At least one Business Day prior to the redemption date specified in the
notice of redemption given as provided in this Section 11.2, the Issuer shall
deposit with the Trustee or with one or more paying agents (or, if the Issuer is
acting as its own paying agent, set aside, segregate and hold in trust as
provided in Section 3.4 hereof) an amount of money sufficient to redeem on the
redemption date all the Securities so called for redemption.

         Section 11.3   Payment of Securities Called for Redemption.

         If notice of redemption has been given as above provided, the
Securities to be redeemed shall become due and payable on the date and at the
place stated in such notice at the redemption price, and on and after said date
(unless the Issuer shall default in the payment of such Securities at the
redemption price) interest on the Securities or portions of Securities so called
for redemption shall cease to accrue and, except as provided in Section 5.5 and
Section 9.4 hereof, such Securities shall cease from and after the date fixed
for redemption to be entitled to any benefit or security under this Indenture,
and the Holders thereof shall have no right in respect of such Securities except
the right to receive the redemption price thereof. On presentation and surrender
of such Securities at a place of payment specified in said notice, said
Securities shall be paid and redeemed by the Issuer at the redemption price;
provided, that any semiannual payment of interest becoming due on the date fixed
for redemption shall be payable to the Holders of such Securities registered as
such on the relevant record date subject to the terms and provisions of Section
2.4 hereof.

         If any Security called for redemption shall not be so paid, upon
surrender thereof for redemption, the principal shall, until paid or duly
provided for, bear interest from the date fixed for redemption at the rate borne
by the Security.

                                       48

<PAGE>   56

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

                                      NRG ENERGY, INC., as Issuer

                                      By:
                                         -------------------------------------
                                          Name:  Leonard A. Bluhm
                                          Title: Executive Vice President and
                                                    Chief Financial Officer

                                      THE BANK OF NEW YORK, as Trustee

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

                                       49
<PAGE>   57

                                    EXHIBIT A

                                FORM OF SECURITY

         UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF
THE DEPOSITORY TRUST COMPANY, TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF
TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IN EXCHANGE FOR THIS
CERTIFICATE OR ANY PORTION HEREOF IS REGISTERED IN THE NAME OF CEDE & CO. OR IN
SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE
DEPOSITORY TRUST COMPANY OR SUCH OTHER REPRESENTATIVE OF THE DEPOSITORY TRUST
COMPANY OR SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF
THE DEPOSITORY TRUST COMPANY (AND ANY PAYMENT HEREON IS MADE TO CEDE & CO.), ANY
TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON
OTHER THAN THE DEPOSITORY TRUST COMPANY OR CEDE & CO. IS WRONGFUL INASMUCH AS
THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

         TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN
WHOLE, BUT NOT IN PART, TO NOMINEES OF THE DEPOSITORY TRUST COMPANY OR TO A
SUCCESSOR THEREOF OR SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS
GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE
RESTRICTIONS SET FORTH IN SECTION 2.6 OF THE INDENTURE REFERRED TO ON THE
REVERSE HEREOF.

                                      A-1

<PAGE>   58

                                                                CUSIP __________
No. [     ]

                                 $[           ]

                                NRG ENERGY, INC.

                               [Title of Security]

         NRG Energy, Inc. (the "Issuer"), for value received hereby promises to
pay to Cede & Co. or registered assigns the principal sum of [ ] Dollars at the
Issuer's office or agency for said purpose initially at the Corporate Trust
Office of ___________________ (herein called the "Trustee") at
__________________________________ and at the office or agency of the Issuer for
said purpose in the Borough of Manhattan, The City of New York, on
________________ in such coin or currency of the United States of America as at
the time of payment shall be legal tender for the payment of public and private
debts, and to pay interest, semi-annually in arrears on ________ and _________
of each year, commencing _____________, on said principal sum in like coin or
currency at the rate per ______ set forth above at said offices or agencies from
the most recent interest payment date to which interest on the Securities has
been paid or duly provided for, unless the date hereof is a date to which
interest on the Securities has been paid or duly provided for, in which case
from the date of this Security, or unless no interest has been paid or duly
provided for on the Securities, in which case from ____________, until payment
of said principal sum has been made or duly provided for. Notwithstanding the
foregoing, if the date hereof is after ________ or ____________, as the case may
be, and before the following _____________ or ____________, this Security shall
bear interest from such _________ or ___________; provided, that if the Issuer
shall default in the payment of interest due on such ________or __________, then
this Security shall bear interest from the immediately preceding ________ or
_________ to which interest on the Securities has been paid or duly provided
for, or, if no interest has been paid or duly provided for on the Securities,
from ___________.

         The interest so payable on any ________ or _________ will, except as
otherwise provided in the Indenture referred to on the reverse hereof, be paid
to the Person in whose name this Security is registered at the close of business
on the ______ day of ____ or the ____ day of ________ preceding such ______ or
________, whether or not such day is a Business Day; provided, that principal,
premium, if any, and interest shall be paid by mailing a check for such to or
upon the written order of the registered Holders of Securities entitled thereto
at their last address as it appears on the Securities Register or, upon written
application to the Trustee by a Holder of $1,000,000 or more in aggregate
principal amount of Securities, by wire transfer of immediately available funds
to an account maintained by such Holder with a bank or other financial
institution. Interest on this Security shall be computed on the basis of a
360-day year of twelve 30-day months.

                                      A-2

<PAGE>   59

         Interest on overdue principal and (to the extent permitted by
applicable law) on overdue installments of interest (including without
limitation during the 30-day period referred to in Section 4.1(b)) shall accrue
at the rate per annum set forth above.

         Reference is made to the further provisions set forth on the reverse
hereof. Such further provisions shall for all purposes have the same effect as
though fully set forth at this place.

         This Security shall not be entitled to any benefit under the Indenture,
or be valid or obligatory, until the certificate of authentication hereof shall
have been duly signed by the Trustee acting under the Indenture.

         IN WITNESS WHEREOF, the Issuer has caused this instrument to be duly
executed under its corporate seal.

                                            NRG ENERGY, INC.
[Seal]

                                            By:________________________________
                                               Name:
                                               Title:

                                            By:________________________________
                                               Name:
                                               Title:
ATTEST:

By:_____________________________
   Name:
   Title:

                     TRUSTEE'S CERTIFICATE OF AUTHENTICATION

Dated:

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

                                         ______________________, as Trustee

                                         __________________________________
                                                 Authorized Signatory

                                      A-3

<PAGE>   60

                               REVERSE OF SECURITY

                                NRG ENERGY, INC.

                               [Title of Security]

         This Security is one of a duly authorized issue of debt securities of
the Issuer issued or to be issued pursuant to an Indenture dated as of
____________ (the "Indenture") (including those terms set forth in the
Authorizing Resolution or supplemental indenture pertaining to the Securities of
the Series of which this Security is a part), duly executed and delivered by the
Issuer to the Trustee. Reference is hereby made to the Indenture and the
Authorizing Resolution or indentures supplemental thereto for a description of
the rights, limitations of rights, obligations, duties and immunities thereunder
of the Trustee, the Issuer and the Holders (the words "Holders" or "Holder"
meaning the registered holders or registered holder) of the Securities.
Capitalized terms used herein, but not otherwise defined herein, shall have the
meanings assigned to them in the Indenture.

         In case an Event of Default shall have occurred and be continuing, the
principal of all the Securities may be declared due and payable, in the manner
and with the effect, and subject to the conditions, provided in the Indenture.
The Indenture provides that in certain events such declaration and its
consequences may be waived by the Holders of a majority in aggregate principal
amount of the Securities then Outstanding and that, prior to any such
declaration, such Holders may waive any past default under the Indenture and its
consequences except a default in the payment of principal of or premium, if any,
or interest on any of the Securities. Any such consent or waiver by the Holder
of this Security (unless revoked as provided in the Indenture) shall be
conclusive and binding upon such Holder and upon all future Holders and owners
of this Security and any Security which may be issued in exchange or
substitution hereof, whether or not any notation thereof is made upon this
Security or such other Securities.

         The Indenture permits the Issuer and the Trustee, with the consent of
the Holders of not less than a majority in aggregate principal amount of the
Securities at the time Outstanding, evidenced as in the Indenture provided, to
modify the Indenture or any supplemental indentures or the rights of the Holders
of the Securities; provided that no such modification shall (a) change the
Stated Maturity of the principal of, or any installment of principal of or
interest on, any Security, or reduce the principal amount thereof, or reduce the
rate or extend the time of payment of interest thereon, or reduce any amount
payable on the redemption thereof or impair or affect the rights of any
Securityholder to institute suit for the payment thereof or make any change in
Section 3.9 of the Indenture (which relates to the obligation of the Issuer to
offer to purchase the Securities upon a Change of Control, as described below)
which adversely affects the rights of the Holders of the Securities without the
consent of the Holder of each Security so affected; (b) reduce the aforesaid
percentage of Securities, the consent of the Holders of which is required for
any such modification or the percentage of Securities, the consent of Holders of
which is required for any waiver provided for in the Indenture; (c) change any
obligation of the Issuer to maintain an office

                                      A-4

<PAGE>   61

or agency for payment of and transfer and exchange of the Securities; or (d)
make certain changes to provisions relating to waiver or to the provision for
supplementing the Indenture; in each case without consent of the Holders of all
Securities then Outstanding.

         No reference herein to the Indenture and no provision of this Security
or of the Indenture shall alter or impair the obligation of the Issuer, which is
absolute and unconditional, to pay the principal of and premium, if any, and
interest on this Security at the place, times, and rate, and in the currency,
herein prescribed.

         At the office or agency of the Issuer referred to on the face hereof
and in the manner subject to the limitations provided in the Indenture,
Securities may be presented for exchange for a like aggregate principal amount
of Securities of other authorized denominations.

         Upon due presentment for registration of transfer of this Security at
the above-mentioned office or agency of the Issuer, a new Security or Securities
of authorized denominations, for a like aggregate principal amount, will be
issued to the transferee as provided in the Indenture. No service charge shall
be made for any such transfer, but the Issuer may require payment of a sum
sufficient to cover any tax or other governmental charge that may be imposed in
relation thereto.

         The Securities may be redeemed in whole or in part (if in part, by lot
or by such other method as the Trustee shall deem fair or appropriate) prior to
Stated Maturity at the option of the Issuer, on any date, upon mailing a notice
of such redemption not less than 30 nor more than 60 days prior to the date
fixed for redemption to the Holders of Securities, all as provided in the
Indenture, at a redemption price equal to the greater of (i) the principal
amount thereof plus accrued and unpaid interest thereon, if any, to the date of
redemption, or (ii) the Make Whole Amount plus accrued and unpaid interest, if
any, from the last payment date to the redemption date. The Make Whole Amount
shall be computed by an independent investment banking institution of national
standing selected by the Issuer and shall equal the sum of the present values of
the Remaining Scheduled Payments discounted, on a semiannual basis (assuming a
360 day year consisting of twelve 30-day months), at a rate equal to the
Treasury Rate plus 25 basis points.

         In the event of a Change of Control (as defined in the Indenture), the
Issuer has the obligation, subject to certain conditions, to offer to purchase
the Securities at 101% of the principal amount thereof plus accrued interest to
the date of purchase in accordance with the procedures set forth in the
Indenture. As further described in the Indenture, a Change of Control will not
be deemed to have occurred if, after giving effect thereto, the Securities are
rated Investment Grade (as defined in the Indenture).

         Subject to payment by the Issuer of a sum sufficient to pay the amount
due on redemption, interest on this Security shall cease to accrue upon the date
duly fixed for redemption of this Security.

                                      A-5

<PAGE>   62

         The Issuer, the Trustee, and any authorized agent of the Issuer or the
Trustee, may deem and treat the registered Holder hereof as the absolute owner
of this Security (whether or not this Security shall be overdue and
notwithstanding any notation of ownership or other writing hereon made by anyone
other than the Issuer or the Trustee or any authorized agent of the Issuer or
the Trustee), for the purpose of receiving payment of, or on account of, the
principal hereof and premium, if any, and, subject to the provisions on the face
hereof, interest hereon and for all other purposes, and neither the Issuer nor
the Trustee nor any authorized agent of the Issuer or the Trustee shall be
affected by any notice to the contrary.

         No recourse shall be had for the payment of the principal of, or
premium, if any, of the interest on this Security, for any claim based hereon,
or otherwise in respect hereof, or based on or in respect of the Indenture or
any indenture supplemental thereto, against any incorporator, shareholder,
officer or director, as such, past, present or future, of the Issuer or of any
successor corporation, either directly or through the Issuer or any successor
corporation, whether by virtue of any constitution, statute or rule of law or by
the enforcement of any assessment or penalty or otherwise, all such liability
being, by the acceptance hereof and as part of the consideration for the issue
hereof, expressly waived and released.

                                      A-6

<PAGE>   63

                               FORM OF ASSIGNMENT

I or we assign and transfer this Security to:

             (Insert assignee's social security or tax I.D. number)

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

and irrevocably appoint:

Agent to transfer this Security on the books of the Issuer.  The Agent may
substitute another to act for him.

Date:  ___________                 Your Signature:
                                   (Sign exactly as your name appears exactly 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 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.

                   FORM OF OPTION OF HOLDER TO ELECT PURCHASE

         If you wish to have this Security purchased by the Issuer pursuant to
Section 3.9 of the Indenture, check the Box:  [insert #].

         If you wish to have a portion of this Security purchased by the Issuer
pursuant to Section 3.9 of the Indenture, state the amount (in original
principal amount):

                                   $ ________________

Date:                              Your Signature:

                                   (Sign exactly as your name appears exactly on
                                   the other side of this Security)

Signature Guarantee:
                                   _______________________________________

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00021-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00021-of-00352.parquet"}]]