Document:

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                                                                   EXHIBIT 10(y)

                          RELIANT ENERGY, INCORPORATED
                                AND SUBSIDIARIES
                       COMMON STOCK PARTICIPATION PLAN FOR
                          DESIGNATED NEW EMPLOYEES AND
                              NON-OFFICER EMPLOYEES

                                  INTRODUCTION

                                    ARTICLE I

                                     PURPOSE

                  The purpose of this Reliant Energy, Incorporated and
Subsidiaries Common Stock Participation Plan for Designated New Employees and
Non-Officer Employees (the "Plan") is to strengthen the alignment of financial
interests of selected employees of Reliant Energy, Incorporated (the "Company")
and its Subsidiaries with those of the Company's shareholders through the
increased ownership of shares of the Company's Common Stock by such employees.
The Plan (i) enhances the Company's ability to maintain a competitive position
in attracting and retaining qualified personnel, (ii) provides a means of
rewarding the outstanding performance of such employees, and (iii) enhances the
interest of such employees in the Company's continued success and progress by
enabling them to obtain a proprietary interest in the Company. Pursuant to the
Plan, the Company may provide for the delivery of shares of Common Stock to (i)
persons not previously employed by the Company or its Subsidiaries as an
inducement to their entering into employment with the Company or its
Subsidiaries and (2) employees who are not officers of the Company who it is
determined should be rewarded for exceptional performance.

                                   ARTICLE II

                                   DEFINITIONS

                  For purposes of the Plan, the following terms shall have the
meanings below stated, subject to the provisions of Section 8.1.

                  "BOARD" means the Board of Directors of the Company.

                  "CAUSE" means Executive's (a) gross negligence in the
performance of Executive's duties, (b) intentional and continued failure to
perform Executive's duties, (c) intentional engagement in conduct which is
materially injurious to the Company or its Subsidiaries (monetarily or
otherwise) or (d) conviction of a felony or a misdemeanor involving moral
turpitude. For this purpose, an act or failure to act on the part of Executive
will be deemed "intentional" only if done or omitted to be done by Executive not
in good faith and without reasonable belief that his/her action or omission was
in the best interest of the Company, and no act or failure to act on the part of
Executive will be deemed "intentional" if it was due primarily to an error in
judgment or negligence.

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                  A "CHANGE IN CONTROL" or "CIC" shall be deemed to have
occurred upon the occurrence of any of the following events:

                  (a) 30% OWNERSHIP CHANGE: Any Person makes an acquisition of
         Outstanding Voting Stock and is, immediately thereafter, the beneficial
         owner of 30% or more of the then Outstanding Voting Stock, unless such
         acquisition is made directly from the Company in a transaction approved
         by a majority of the Incumbent Directors; or any group is formed that
         is the beneficial owner of 30% or more of the Outstanding Voting Stock;
         or

                  (b) BOARD MAJORITY CHANGE: Individuals who are Incumbent
         Directors cease for any reason to constitute a majority of the members
         of the Board; or

                  (c) MAJOR MERGERS AND ACQUISITIONS: Consummation of a Business
         Combination unless, immediately following such Business Combination,
         (i) all or substantially all of the individuals and entities that were
         the beneficial owners of the Outstanding Voting Stock immediately prior
         to such Business Combination beneficially own, directly or indirectly,
         more than 70% of the then outstanding shares of voting stock of the
         parent corporation resulting from such Business Combination in
         substantially the same relative proportions as their ownership,
         immediately prior to such Business Combination, of the Outstanding
         Voting Stock, (ii) if the Business Combination involves the issuance or
         payment by the Company of consideration to another entity or its
         shareholders, the total fair market value of such consideration plus
         the principal amount of the consolidated long-term debt of the entity
         or business being acquired (in each case, determined as of the date of
         consummation of such Business Combination by a majority of the
         Incumbent Directors) does not exceed 50% of the sum of the fair market
         value of the Outstanding Voting Stock plus the principal amount of the
         Company's consolidated long-term debt (in each case, determined
         immediately prior to such consummation by a majority of the Incumbent
         Directors), (iii) no Person (other than any corporation resulting from
         such Business Combination) beneficially owns, directly or indirectly,
         30% or more of the then outstanding shares of voting stock of the
         parent corporation resulting from such Business Combination and (iv) a
         majority of the members of the board of directors of the parent
         corporation resulting from such Business Combination were Incumbent
         Directors of the Company immediately prior to consummation of such
         Business Combination; or

                  (d) MAJOR ASSET DISPOSITIONS: Consummation of a Major Asset
         Disposition unless, immediately following such Major Asset Disposition,
         (i) individuals and entities that were beneficial owners of the
         Outstanding Voting Stock immediately prior to such Major Asset
         Disposition beneficially own, directly or indirectly, more than 70% of
         the then outstanding shares of voting stock of the Company (if it
         continues to exist) and of the entity that acquires the largest portion
         of such assets (or the entity, if any, that owns a majority of the
         outstanding voting stock of such acquiring entity) and (ii) a majority
         of the members of the board of directors of the Company (if it
         continues to exist) and of the entity that acquires the

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         largest portion of such assets (or the entity, if any, that owns a
         majority of the outstanding voting stock of such acquiring entity) were
         Incumbent Directors of the Company immediately prior to consummation of
         such Major Asset Disposition.

For purposes of the foregoing,

                  (1) the term "Person" means an individual, entity or group;

                  (2) the term "group" is used as it is defined for purposes of
         Section 13(d)(3) of the Securities Exchange Act of 1934 (the "Exchange
         Act");

                  (3) the term "beneficial owner" is used as it is defined for
         purposes of Rule 13d-3 under the Exchange Act;

                  (4) the term "Outstanding Voting Stock" means outstanding
         voting securities of the Company entitled to vote generally in the
         election of directors; and any specified percentage or portion of the
         Outstanding Voting Stock (or of other voting stock) shall be determined
         based on the combined voting power of such securities;

                  (5) the term "Incumbent Director" means a director of the
         Company (x) who was a director of the Company on September 1, 1997 or
         (y) who becomes a director subsequent to such date and whose election,
         or nomination for election by the Company's shareholders, was approved
         by a vote of a majority of the Incumbent Directors at the time of such
         election or nomination, except that any such director shall not be
         deemed an Incumbent Director if his or her initial assumption of office
         occurs as a result of an actual or threatened election contest or other
         actual or threatened solicitation of proxies by or on behalf of a
         Person other than the Board;

                  (6) the term "election contest" is used as it is defined for
         purposes of Rule 14a-11 under the Exchange Act;

                  (7) the term "Business Combination" means (x) a merger or
         consolidation involving the Company or its stock or (y) an acquisition
         by the Company, directly or through one or more subsidiaries, of
         another entity or its stock or assets;

                  (8) the term "parent corporation resulting from a Business
         Combination" means the Company if its stock is not acquired or
         converted in the Business Combination and otherwise means the entity
         which as a result of such Business Combination owns the Company or all
         or substantially all the Company's assets either directly or through
         one or more subsidiaries; and

                  (9) the term "Major Asset Disposition" means the sale or other
         disposition in one transaction or a series of related transactions of
         70% or more of the assets of the Company and its Subsidiaries on a
         consolidated basis; and any specified

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         percentage or portion of the assets of the Company shall be based on
         fair market value, as determined by a majority of the Incumbent
         Directors.

                  "CODE" means the Internal Revenue Code of 1986, as amended
from time to time.

                  "COMMITTEE" means the Special Stock Award Committee or the
Compensation Committee of the Board of Directors of the Company, it being
understood that either such Committee shall have authority to grant Stock Awards
and take other action contemplated by this Plan.

                  "COMMON STOCK" means, subject to the provisions of Section
10.3, the presently authorized common stock, without par value, of the Company.

                  "COMPANY" means Reliant Energy, Incorporated, a Texas
corporation.

                  "DISABILITY" means a physical or mental impairment of
sufficient severity such that an Employee is both eligible for and in receipt of
benefits under the long-term disability provisions of the Company's benefit
plans.

                  "EMPLOYEE" means an employee of the Company or a Subsidiary.

                  "EMPLOYER" means the Company or Subsidiary that employs the
Employee.

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

                  "FAIR MARKET VALUE" means the average of high and low sales
price of a share of Common Stock on the New York Stock Exchange--Composite
Transactions reporting system, as reported in The Wall Street Journal on the
date as of which such value is being determined or, if no sales occurred on such
day, then on the next preceding day on which there were such sales.

                  "PARTICIPANT" means a person selected to participate in this
Plan pursuant to the terms hereof.

                  "PLAN" means the Reliant Energy, Incorporated and Subsidiaries
Common Stock Participation Plan for Designated New Employees and Non-Officer
Employees, as set forth herein and as from time to time amended.

                  "RESTRICTED PERIOD" means the period of employment established
by the Committee which the Participant must complete for the restrictions to
lapse pursuant to Section 6.2.

                  "STOCK AWARD" means an award of shares of Common Stock or
units denominated in shares of Common Stock, of options to purchase shares of
Common Stock, or of the right to a payment measured by the appreciation in the
value of shares of Common Stock or the value of units denominated in shares of
Common Stock, granted by the Company to a Participant pursuant to Section 5.1.

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                  "SUBSIDIARY" means a subsidiary corporation of the Company as
defined in Section 424(f) of the Code.

                                   ARTICLE III

                              RESERVATION OF SHARES

                  The aggregate number of shares of Common Stock which may be
issued under this Plan shall not exceed One Million (1,000,000) shares, subject
to adjustment as hereinafter provided. All or any part of such One Million
shares may be issued pursuant to Stock Awards. The shares of Common Stock which
may be granted pursuant to Stock Awards will consist of either authorized but
unissued shares of Common Stock or shares of Common Stock which have been issued
and which shall have been heretofore or hereafter reacquired by the Company as
treasury shares. The total number of shares authorized under this Plan shall be
subject to increase or decrease in order to give effect to the adjustment
provision of Section 10.3 and to give effect to any amendment adopted as
provided in Section 9.1. The foregoing limitation on the number of shares of
Common Stock issuable under the Plan is a limitation on the aggregate number of
shares of Common Stock issued, net of any shares of Common Stock subject to a
Stock Award implemented by delivery of certificates that are returned to the
Company as provided in Article V, but subject to such other rules and procedures
concerning the counting of shares against the Plan maximum as the Committee may
deem appropriate.

                                   ARTICLE IV

                            PARTICIPATION IN THE PLAN

         4.1 ELIGIBILITY TO RECEIVE STOCK AWARDS. Stock Awards under this Plan
may be granted only to persons selected by the Committee who are not officers of
the Company and who are Employees of the Company or a Subsidiary on the date the
Stock Award is granted. Stock Awards under this Plan may be granted to any
Employee who has become entitled to an award pursuant to another incentive plan
of the Company or a Subsidiary provided that the award is consistent with the
purposes of this Plan.

         4.2 PARTICIPATION NOT GUARANTEE OF EMPLOYMENT. Nothing in this Plan or
in the instrument evidencing the grant of a Stock Award shall in any manner be
construed to limit in any way the right of the Company or a Subsidiary to
terminate a Participant's employment at any time, without regard to the effect
of such termination on any rights such Participant would otherwise have under
this Plan, or give any right to such Participant to remain employed by the
Company or a Subsidiary in any particular position or at any particular rate of
compensation.

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                                    ARTICLE V

                                  STOCK AWARDS

         5.1 GRANT OF STOCK AWARDS.

         (a) SELECTION OF PARTICIPANTS. Subject to the terms of this Plan, the
Committee shall select the persons to whom Stock Awards shall be awarded.
Subject to the eligibility requirements of Section 4.1, awards pursuant to other
incentive plans of the Company or any Subsidiaries denominated in shares of
Common Stock, in the discretion of the Committee, may be granted to Employees
pursuant to the terms of the Plan.

         (b) AWARD OF SHARES. The Committee shall determine the number of shares
of Common Stock covered by each Stock Award awarded to a Participant, as well as
all other terms and conditions of each Stock Award. Shares issued pursuant to
the terms of other incentive plans of the Company or a Subsidiary may be issued
subject to terms established with reference to such other plans. Shares of
Common Stock may be awarded subject to a Restricted Period, without any
restriction whatsoever or subject to such other vesting and forfeiture
conditions, which may be performance based, as may be established by the
Committee. If Stock Awards are issued subject to a Restricted Period, then on or
about the close of, and, if appropriate and in accordance with Section 6.3 or
6.4, during the term of, each Restricted Period, the Committee shall determine
whether restrictions set forth in Article VI hereof shall lapse with respect to
a portion or all of the shares awarded under a Stock Award.

                  The Committee may implement the grant of a Stock Award subject
to a Restricted Period by (i) credit to a bookkeeping account maintained by the
Company evidencing the accrual to a Participant of unsecured and unfunded rights
to receive, subject to the terms of the Stock Award, shares of Common Stock or
(ii) delivery of certificates for shares of Common Stock to the Participant, who
must execute appropriate stock powers in blank and return the certificates and
stock powers to the Company to be held in escrow for future delivery in
accordance with the terms of the Stock Award. The grant of a Stock Award subject
to other vesting and forfeiture conditions shall be implemented in a manner
determined by the Committee.

         (c) FORM OF INSTRUMENT. Each Stock Award shall be made pursuant to an
instrument prescribed in form by the Committee. Such instrument shall specify
the number of shares covered thereby and the restrictions, if any, which, if not
achieved, may cause all or part of the shares to be forfeited.

         5.2 RIGHTS WITH RESPECT TO SHARES.

         (a) AWARD BY BOOKKEEPING ENTRY. No Participant who is granted a Stock
Award implemented by credit to a Company bookkeeping account shall have any
rights as a stockholder by virtue of such grant until shares are actually issued
or delivered to the Participant. The Committee may establish and express in the
written instrument evidencing the Stock Award terms and conditions under which
the Participant granted such Stock Award shall be entitled to receive an
amount equivalent to any dividend payable with respect to the number of shares
which, as of the

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record date for which dividends are payable, have been credited but not
delivered to the Participant. At the Committee's discretion, any such dividend
equivalents (i) may be paid at such time or times during the period when the
shares are as yet undelivered pursuant to the terms of the Stock Award, (ii) may
be paid at the time the shares to which the dividend equivalents apply are
delivered, or (iii) may be reflected by the credit of additional full or
fractional shares to three decimal places in an amount equal to the amount of
such dividend equivalents divided by the Fair Market Value of a full share on
the date of payment of the dividend on which the dividend equivalent is based,
all as shall be expressed in the written instrument evidencing the Stock Award.
Any arrangements for the payment or credit of dividend equivalents shall be
terminated if, and to the extent that, under the terms and conditions so
established, the right to receive shares pursuant to the terms of the Stock
Award shall terminate or lapse.

         (b) AWARD BY STOCK CERTIFICATE. Each Participant to whom a Stock Award
consisting of shares represented by a stock certificate has been made shall have
absolute ownership of such shares including the right to vote the same and to
receive dividends thereon, subject, however, to the terms, conditions and
restrictions, if any, described in this Plan and in the instrument evidencing
the grant of the Stock Award.

                  Notwithstanding the foregoing, shares of Common Stock
transferred pursuant to a Stock Award subject to a Restricted Period shall be
held in escrow pursuant to an agreement satisfactory to the Committee until such
time as the Committee shall have determined whether the restrictions set forth
in Article VI shall have lapsed. Each such escrow agreement shall provide,
without limitation, that the shares of Common Stock subject to such agreement
are subject to the restrictions set forth in Article VI.

                                   ARTICLE VI

                   STOCK AWARDS SUBJECT TO A RESTRICTED PERIOD

         6.1 RESTRICTIONS. Each Stock Award granted under this Plan subject to a
Restricted Period shall contain the following terms, conditions and restrictions
and such additional terms, conditions and restrictions as may be determined by
the Committee.

                  Until the restrictions set forth in this Section 6.1 shall
lapse pursuant to this Article VI, shares of Common Stock awarded to a
Participant pursuant to each Stock Award:

                  (a) shall not be sold, assigned, transferred, pledged,
         hypothecated or otherwise disposed of; and

                  (b) shall be returned to the Company, and all rights of the
         Participant to such shares shall terminate without any payment of
         consideration by the Company, if the Participant's continuous
         employment with the Company or any of its Subsidiaries shall terminate
         for any reason, except as provided in Section 6.2, 6.3 or 6.4.

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         6.2 LAPSE OF RESTRICTIONS DUE TO TERMINATION OF RESTRICTED PERIOD. At
the time of the Stock Award, there may be established for a Participant a
"Restricted Period" which shall be such length of time as established by the
Committee in its discretion. Shares of Common Stock awarded to Participants may
not be sold, assigned, transferred, pledged, otherwise encumbered or disposed
of, except as hereinafter provided, during the Restricted Period. Except for
such restrictions on transfer, the Participant, as owner of such shares, shall
have all the rights of the holder of Common Stock, including but not limited to,
the right to vote the same and to receive all dividends paid on such shares.

         6.3 LAPSE OF RESTRICTIONS DUE TO CERTAIN TERMINATIONS OF EMPLOYMENT.
Unless otherwise provided by the Committee with respect to a particular Stock
Award, if a Participant who has been in the continuous employment of any
Employer since the date on which a Stock Award was granted to such Participant
shall, while in such employment and prior to the close of the Restricted Period
with respect to which such Stock Award was granted, terminate employment by
reason of death, Disability or retirement on or after attainment of age
fifty-five (55), the restrictions set forth in Section 6.1 shall lapse with
respect to all of the shares subject to the Award.

         6.4 TREATMENT UPON CHANGE IN CONTROL. Unless otherwise provided by the
Committee with respect to a particular Stock Award, notwithstanding any
provision of Section 6.1 or any other provision of this Plan, forthwith upon the
occurrence of any Change in Control of the Company, the Company shall pay cash
to each Participant to whom a Stock Award has been made (and with respect to
which the restrictions have not previously lapsed) in an amount equal to the
number of shares of Common Stock granted under this Plan pursuant to outstanding
Stock Awards times the Fair Market Value on the date of the Change in Control.

                                   ARTICLE VII

                                  TAX PAYMENTS

                  A Participant who has received shares of Common Stock pursuant
to a Stock Award may also, at the discretion of the Committee, receive from the
Company a cash payment in an amount determined by the Committee, if any, not to
exceed that amount sufficient to pay such Participant's tax liability with
respect to (i) such shares and (ii) such cash payment.

                                  ARTICLE VIII

                           ADMINISTRATION OF THE PLAN

         8.1 THE COMMITTEE. This Plan shall be administered solely by the
Committee. The Committee shall have full and final authority to interpret this
Plan and the instruments evidencing Stock Awards granted hereunder, to
prescribe, amend and rescind rules and regulations, if any, relating to this
Plan and to make all determinations necessary or advisable for the
administration of this Plan. The Committee's determination in all matters
referred to herein shall be conclusive and binding for all purposes and upon all
persons including, but without limitation, the Company, all Subsidiaries, the
shareholders of the Company, the Committee and each of the members thereof, as
well as Participants and Employees and their respective successors in interest.

                                      -8-
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         8.2 LIABILITY OF COMMITTEE. No member of the Committee shall be liable
for anything done or omitted to be done by such member or by any other member of
the Committee or by any person to whom authority is delegated as provided in the
last sentence of Section 8.1 in connection with this Plan, except for the
willful misconduct of such member or as expressly required by law. The Committee
shall have power to engage outside consultants, auditors or other professionals
to assist in the fulfillment of the Committee's duties under this Plan at the
Company's expense.

         8.3 DETERMINATION OF THE COMMITTEE. In making its determinations
concerning the individuals who will become Participants, as well as the number
of shares to be awarded to each Participant, the Committee shall take into
account such factors as the Committee may deem relevant. The Committee shall
also determine the form of Stock Awards to be issued under this Plan and the
terms and conditions to be included therein, provided such terms and conditions
are not inconsistent with the terms of this Plan. The Committee may, in its sole
discretion, waive any provisions of any Stock Award, provided such waiver is not
inconsistent with the terms of this Plan as then in effect.

                                   ARTICLE IX

                        AMENDMENT AND TERMINATION OF PLAN

         9.1 AMENDMENT, MODIFICATION, SUSPENSION OR TERMINATION. The Board may
amend, modify, suspend or terminate the Plan at any time except that no
amendment or alteration that would impair the rights of any Participant under
any outstanding Stock Award shall be made without such Participant's consent.

         9.2 TERMINATION. The Board may at any time terminate this Plan as of
any date specified in a resolution adopted by the Board. No Stock Awards may be
granted after this Plan has terminated. After this Plan has terminated, the
function of the Committee with respect to this Plan will be limited to
determinations, interpretations and other matters provided herein with respect
to Stock Awards previously granted.

                                    ARTICLE X

                            MISCELLANEOUS PROVISIONS

         10.1 RESTRICTIONS UPON GRANT OF STOCK AWARDS. The listing upon the New
York Stock Exchange or the registration or qualification under any federal or
state law of any shares of Common Stock to be granted pursuant to this Plan
(whether to permit the grant of Stock Awards or the resale or other disposition
of any such shares of Common Stock by or on behalf of the Participants receiving
such shares) may be necessary or desirable and, in any event, if the Committee
in its sole discretion so determines, delivery of the certificates for such
shares of Common Stock shall not be made until such listing, registration or
qualification shall have been completed. In such connection, the Company agrees
that it will use its best efforts to effect any such listing, registration or
qualification, provided, however, that the Company shall not be required to use
its best efforts to effect such registration under the Securities Act of 1933,
as amended, other than on Form S-8, as

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presently in effect, or other such forms as may be in effect from time to time
calling for information comparable to that presently required to be furnished
under Form S-8.

         10.2 RESTRICTIONS UPON RESALE OF UNREGISTERED STOCK. If the shares of
Common Stock that have been transferred to a Participant pursuant to the terms
of this Plan are not registered under the Securities Act of 1933, as amended,
pursuant to an effective registration statement, such Participant, if the
Committee deems it advisable, may be required to represent and agree in writing
(i) that any shares of Common Stock acquired by such Participant pursuant to
this Plan will not be sold except pursuant to Rule 144 under the Securities Act
of 1933 (the "1933 Act"), pursuant to an effective registration statement under
the 1933 Act, or pursuant to an exemption from registration under said Act and
(ii) that such Participant is acquiring such shares of Common Stock for such
Participant's own account and not with a view to the distribution thereof.

         10.3 ADJUSTMENTS.

         (a) The existence of outstanding Stock Awards shall not affect in any
manner the right or power of the Company or its shareholders to make or
authorize any or all adjustments, recapitalizations, reorganizations or other
changes in the capital stock of the Company or its business or any merger or
consolidation of the Company, or any issue of bonds, debentures, preferred or
prior preference stock (whether or not such issue is prior to, on a parity with
or junior to the Common Stock) or the dissolution or liquidation of the Company,
or any sale or transfer of all or any part of its assets or business, or any
other corporate act or proceeding of any kind, whether or not of a character
similar to that of the acts or proceedings enumerated above.

         (b) In the event of any subdivision or combination of outstanding
shares of Common Stock or declaration of a dividend on the Common Stock payable
in shares of Common Stock, the Committee may adjust proportionally the number of
shares of Common Stock reserved under this Plan and covered by outstanding Stock
Awards denominated in Common Stock or units of Common Stock and may also adjust,
if it deems appropriate, any price criteria or other determination in respect of
such Stock Awards. In the event of any consolidation or merger of the Company
with another corporation or entity or the adoption by the Company of a plan of
exchange affecting the Common Stock or any distribution to holders of Common
Stock of securities or property (other than normal cash dividends or dividends
payable in Common Stock) or any reclassification of this Common Stock, the
Committee may make such adjustments or other provisions as it may deem
equitable, including adjustments to avoid fractional shares, to give proper
effect to such event. In the event of a corporate merger, consolidation,
acquisition of property or stock, or liquidating distribution, the Committee
shall be authorized to issue or assume Stock Awards, regardless of whether in a
transaction to which Section 424(a) of the Code applies, by means of
substitution of new Stock Awards for previously issued Stock Awards or an
assumption of previously issued Stock Awards, or to make provision for the
acceleration of the exercisability of, or lapse of restrictions with respect to,
Stock Awards and the termination of unexercised rights with respect to Stock
Awards in connection with such transaction.

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         10.4 RESTRICTIVE LEGENDS.

         (a) Certificates for shares of Common Stock delivered pursuant to Stock
Awards shall bear an appropriate legend conforming to the requirements of
applicable law referring to the terms, conditions and restrictions described in
this Plan and in the instruments evidencing the grant of the Stock Awards. Any
attempt to dispose of any such shares of Common Stock in contravention of the
terms, conditions and restrictions described in this Plan or in the instruments
evidencing the grant of the Stock Award shall be ineffective. The Company may
also place appropriate "stop transfer" instructions in the stock transfer books
of the Company with respect to shares of Common Stock covered by a Stock Award.

         (b) Any shares of Common Stock received by a Participant as a stock
dividend on, or as a result of stock splits, combinations, exchanges of shares,
reorganizations, mergers, consolidations or otherwise with respect to, shares of
Common Stock received pursuant to a Stock Award shall have the same status and
bear the same legend as the shares received pursuant to the Stock Award.

         10.5 WITHHOLDING OF TAXES: The Committee shall deduct applicable taxes
(without regard to any alternative rule permitting the use of a flat percentage
rate in computing such applicable income tax withholding amounts) with respect
to any Stock Award, and withhold, at the time of delivery or other appropriate
time, an appropriate amount of cash or number of shares of Common Stock or a
combination thereof for payment of taxes required by law, such withholding to be
administered on a uniform basis (not involving any election by any Participant).
If shares of Common Stock are used to satisfy tax withholding, such shares shall
be valued based on the Fair Market Value when the tax withholding is required to
be made.

         10.6 POOLING OF INTERESTS: In the event that the Company is party to a
transaction which is otherwise intended to qualify for "pooling of interests"
accounting treatment then (a) the provisions of the Plan shall, to the extent
practicable, be interpreted so as to permit such accounting treatment, and (b)
to the extent that the application of clause (a) of this sentence does not
preserve the availability of such accounting treatment, then, to the extent that
any of the provisions of the Plan or the terms or provisions of any outstanding
award or the manner or timing of the adoption of the Plan or the making of any
award thereunder disqualifies the transaction as a "pooling" transaction, the
Board may amend any provisions of the Plan, amend the provisions of any
outstanding award and/or declare any of the provisions of the Plan or the entire
Plan as well as any outstanding awards null and void if and to the extent
necessary (including declaring such provision or provisions to be null and void
as of the date hereof) so that such transaction may be accounted for as a
"pooling of interests." All determinations with respect to this paragraph shall
be made by the Board, based upon the advice of the accounting firm whose opinion
with respect to "pooling of interests" is required as a condition to the
consummation of such transaction.

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         10.7 EFFECTIVE DATE OF PLAN: This Plan shall be effective as of March
4, 1998.

                                      RELIANT ENERGY, INCORPORATED

                                      By     /s/ LEE W. HOGAN
                                        ----------------------------------------
                                         Name:   Lee Hogan
                                              ----------------------------------
                                         Title:  Vice Chairman
                                               ---------------------------------

ATTEST:

/s/ RUFUS SCOTT
-------------------------------
Assistant Corporate Secretary

                                      -12-<PAGE>   1
                                                                     EXHIBIT 4.C

                                                                  EXECUTION COPY

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

                          FIFTH SUPPLEMENTAL INDENTURE

                                     BETWEEN

                               EL PASO CORPORATION

                                       AND

                            THE CHASE MANHATTAN BANK
                                   AS TRUSTEE

                                    ---------

                                   DATED AS OF

                                FEBRUARY 28, 2001

                     TO INDENTURE DATED AS OF MAY 10, 1999

                                    ---------

            ZERO COUPON CONVERTIBLE DEBENTURES DUE FEBRUARY 28, 2021

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<PAGE>   2

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
<S>                 <C>                                                            <C>
ARTICLE I THE 2021 DEBENTURES........................................................2
   Section 101       Designation of 2021 Debentures; Establishment of Form...........2
   Section 102       Transfer and Exchange...........................................3
   Section 103       Amount..........................................................8
   Section 104       Accrual of Original Issue Discount; Interest....................8
   Section 105       Additional Interest.............................................9
   Section 106       Denominations...................................................9
   Section 107       Place of Payment................................................9
   Section 108       Redemption......................................................9
   Section 109       Conversion......................................................9
   Section 110       Maturity........................................................9
   Section 111       Repurchase.....................................................10
   Section 112       Covenants......................................................10
   Section 113       Amount Due Upon Event of Default...............................10
   Section 114       Discharge of Liability on 2021 Debentures......................10
   Section 115       Other Terms of 2021 Debentures.................................10
ARTICLE II AMENDMENTS TO THE INDENTURE..............................................11
   Section 201       Amendments Applicable Only to 2021 Debentures..................11
   Section 202       Definitions....................................................11
   Section 203       Definition of Outstanding......................................15
   Section 204       Registration, Registration of Transfer and Exchange............15
   Section 205       Mutilated, Destroyed, Lost and Stolen Securities...............15
   Section 206       Payment of Interest; Interest Rights Preserved.................16
   Section 207       Cancellation...................................................16
   Section 208       Redemption.....................................................16
   Section 209       Consolidation, Merger and Sale.................................18
   Section 210       Defaults and Remedies..........................................19
   Section 211       Collection of Indebtedness and Suits for Enforcement
                       by Trustee...................................................19
   Section 212       Unconditional Right of Holders to Receive Principal, Premium
                       and Interest.................................................20
   Section 213       Supplemental Indentures Without Consent of Holders.............20
   Section 214       Supplemental Indenture with Consent of Holder..................20
   Section 215       Maintenance of Office or Agency................................21
   Section 216       Conversion, Tax Event, Repurchase..............................21
ARTICLE III MISCELLANEOUS PROVISIONS................................................49
   Section 301       Integral Part..................................................49
   Section 302       General Definitions............................................49
   Section 303       Adoption, Ratification and Confirmation........................50
   Section 304       Trust Indenture Act Controls...................................50
   Section 305       Governing Law..................................................50
   Section 306       Severability...................................................50
   Section 307       Counterpart Originals..........................................50
   Section 308       Successors.....................................................50
   Section 309       Table of Contents, Headings, etc...............................50
   Section 310       Benefit of Fifth Supplemental Indenture........................51
   Section 311       Acceptance by Trustee..........................................51
</TABLE>

                                      -i-

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         THIS FIFTH SUPPLEMENTAL INDENTURE, dated as of February 28, 2001, is
between El Paso Corporation, (formerly known as El Paso Energy Corporation), a
Delaware corporation (the "Company"), and The Chase Manhattan Bank, as trustee
(the "Trustee").

                             RECITALS OF THE COMPANY

         WHEREAS, the Company has heretofore executed and delivered to the
Trustee an Indenture, dated as of May 10, 1999 (the "Original Indenture," as
supplemented by the First Supplemental Indenture, dated as of May 10, 1999, the
Second Supplemental Indenture, dated as of July 12, 1999, the Third Supplemental
Indenture, dated as of July 12, 1999, and the Fourth Supplemental Indenture,
dated as of May 31, 2000), (collectively and as further supplemented by this
Fifth Supplemental Indenture, dated as of February 28, 2001, the "Indenture"),
providing for the issuance from time to time of one or more series of the
Company's Securities; and

         WHEREAS, Section 901(5) of the Original Indenture provides that the
Company and the Trustee may from time to time enter into one or more indentures
supplemental thereto to establish the form or terms of Securities of a new
series; and

         WHEREAS, Section 901(3) of the Original Indenture permits the execution
of supplemental indentures without the consent of any Holders to add to the
covenants of the Company for the benefit of, and to add any additional Events of
Default with respect to, all or any series of Securities; and

         WHEREAS, Section 901(6) of the Original Indenture permits the execution
of supplemental indentures without the consent of any Holders to make provisions
with respect to matters or questions arising under the Indenture, provided that
such provisions do not adversely affect the interests of the Holders of
Outstanding Securities in any material respect; and

         WHEREAS, Sections 201 and 301 of the Original Indenture provide that
the Company may enter into supplemental indentures to establish the terms and
provisions of a series of Securities issued pursuant to the Indenture; and

         WHEREAS, the Company desires to issue Zero Coupon Convertible
Debentures due February 28, 2021 (the "2021 Debentures"), a new series of
Security, the issuance of which was authorized by or pursuant to resolutions of
the Board of Directors of the Company; and

         WHEREAS, the Company, pursuant to the foregoing authority, proposes in
and by this Fifth Supplemental Indenture to supplement and amend in certain
respects the Original Indenture insofar as it will apply only to the 2021
Debentures (and not to any other series) in certain respects; and

         WHEREAS, all things necessary have been done to make the 2021
Debentures, when executed by the Company and authenticated and delivered
hereunder and duly issued by the Company, the valid obligations of the Company,
and to make this Fifth Supplemental Indenture a valid agreement of the Company,
in accordance with their and its terms.

<PAGE>   4

         NOW THEREFORE:

         In consideration of the premises provided for herein, the Company and
the Trustee mutually covenant and agree for the equal and proportionate benefit
of all Holders of the 2021 Debentures as follows:

                                   ARTICLE I

                               THE 2021 DEBENTURES

Section 101 Designation of 2021 Debentures; Establishment of Form.

         There shall be a series of Securities designated "Zero Coupon
Convertible Debentures due February 28, 2021" of the Company, and the form
thereof shall be substantially as set forth in Annex A hereto, which is
incorporated into and shall be deemed a part of this Fifth Supplemental
Indenture, in each case with such appropriate insertions, omissions,
substitutions and other variations as are required or permitted by the
Indenture, and may have such letters, numbers or other marks of identification
and such legends or endorsements placed thereon as may be required to comply
with the rules of any securities exchange or as may, consistently herewith, be
determined by the officers of the Company executing such 2021 Debentures, as
evidenced by their execution of the 2021 Debentures.

         (a) Restricted Global Securities. All of the 2021 Debentures are
initially being offered and sold to Credit Suisse First Boston Corporation
("CSFB"), as initial purchaser ("Initial Purchaser") pursuant to the Purchase
Agreement, and offered and sold by CSFB to qualified institutional buyers as
defined in Rule 144A (collectively, "QIBs" or individually a "QIB") in reliance
on Rule 144A under the Securities Act and shall be issued initially in the form
of one or more Restricted Global Securities, which shall be deposited on behalf
of the purchasers of the 2021 Debentures represented thereby with the Trustee,
at its Corporate Trust Office, as Security Custodian for the depositary, The
Depository Trust Company ("DTC") (such depositary, or any successor thereto,
being hereinafter referred to as the "Depositary"), and registered in the name
of its nominee, Cede & Co., duly executed by the Company and authenticated by
the Trustee as hereinafter provided. The aggregate Principal Amount of a
Restricted Global Security may from time to time be increased or decreased by
adjustments made on the records of the Security Custodian as hereinafter
provided, subject in each case to compliance with the Applicable Procedures.
Until sold pursuant to Rule 144, pursuant to an effective registration statement
under the Securities Act or pursuant to any other available exemption (other
than Rule 144A) from the registration requirements of the Securities Act, the
Company agrees that if it is not subject to the requirements of Section 13 or
15(d) of the Exchange Act, the Company shall furnish to all Holders of the
Securities and prospective purchasers of same, promptly upon their request, the
information required to be delivered pursuant to Rule 144(d)(4) of the rules and
regulations promulgated under the Securities Act.

         (b) Global Securities in General. Each Global Security shall represent
such of the outstanding 2021 Debentures as shall be specified therein and each
shall provide that it shall represent the aggregate amount of outstanding 2021
Debentures from time to time endorsed thereon and that the aggregate amount of
outstanding 2021 Debentures represented thereby may

                                      -2-
<PAGE>   5

from time to time be reduced or increased, as appropriate, to reflect exchanges,
redemptions, purchases or conversions of such 2021 Debentures. Any endorsement
of a Global Security to reflect the amount of any increase or decrease in the
Principal Amount of Outstanding 2021 Debentures represented thereby shall be
made by the Security Custodian in accordance with the standing instructions and
procedures existing between the Depositary and the Security Custodian.

         Members of, or participants in, the Depositary ("Agent Members") shall
have no rights under this Indenture with respect to any Global Security held on
their behalf by the Depositary or under the Global Security, and the Depositary
(including, for this purpose, its nominee) may be treated by the Company, the
Trustee and any agent of the Company or the Trustee as the absolute owner and
Holder of such Global Security for all purposes whatsoever. Notwithstanding the
foregoing, nothing herein shall (A) prevent the Company, the Trustee or any
agent of the Company or the Trustee from giving effect to any written
certification, proxy or other authorization furnished by the Depositary or (B)
impair, as between the Depositary and its Agent Members, the operation of
customary practices governing the exercise of the rights of a Holder of any 2021
Debenture.

         (c) Certificated Securities. Certificated Securities shall be issued
only under the limited circumstances provided in Section 102(a)(1) hereof.

         The Company initially appoints The Depository Trust Company to act as
Depositary with respect to the Global Securities.

         The Company initially appoints the Trustee to act as Paying Agent,
Security Registrar and Conversion Agent with respect to the 2021 Debentures.

Section 102 Transfer and Exchange.

         (a) Transfer and Exchange of Global Securities.

               (1) Certificated Securities shall be issued in exchange for
          interests in the Global Securities only if (x) the Depositary notifies
          the Company that it is unwilling or unable to continue as depositary
          for the Global Securities or if it at any time ceases to be a
          "clearing agency" registered under the Exchange Act if so required by
          applicable law or regulation and a successor depositary is not
          appointed by the Company within 90 days, or (y) an Event of Default
          has occurred and is continuing. In either case, the Company shall
          execute, and the Trustee shall, upon receipt of a Company Order (which
          the Company agrees to deliver promptly), authenticate and deliver
          Certificated Securities in an aggregate Principal Amount equal to the
          Principal Amount of such Global Securities in exchange therefor. Only
          Restricted Certificated Securities shall be issued in exchange for
          beneficial interests in Restricted Global Securities, and only
          Unrestricted Certificated Securities shall be issued in exchange for
          beneficial interests in Unrestricted Global Securities. Certificated
          Securities issued in exchange for beneficial interests in Global
          Securities shall be registered in such names and shall be in such
          authorized denominations as the Depositary, pursuant to instructions
          from its direct or indirect participants or otherwise, shall instruct
          the Trustee. The Trustee shall deliver or cause to

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<PAGE>   6

          be delivered such Certificated Securities to the persons in whose
          names such Securities are so registered. Such exchange shall be
          effected in accordance with the Applicable Procedures. Nothing herein
          shall require the Trustee to communicate directly with beneficial
          owners, and the Trustee shall in connection with any transfers
          hereunder be entitled to rely on instructions received through the
          registered Holder.

               (2) Notwithstanding any other provisions of this Indenture other
          than the provisions set forth in Section 102(a)(1) hereof, a Global
          Security may not be transferred as a whole except by the Depositary to
          a nominee of the Depositary or by a nominee of the Depositary to the
          Depositary or another nominee of the Depositary or by the Depositary
          or any such nominee to a successor Depositary or a nominee of such
          successor Depositary.

         (b) Transfer and Exchange of Certificated Securities. When Certificated
Securities are presented by a Holder to an office or agency of the Company
maintained pursuant to Section 1002 of the Indenture for such purpose (a
"Registrar") with a request:

               (1) to register the transfer of the Certificated Securities to a
          person who will take delivery thereof in the form of Certificated
          Securities only; or

               (2) to exchange such Certificated Securities for an equal
          Principal Amount of Certificated Securities of other authorized
          denominations,

such Registrar shall register the transfer or make the exchange as requested;
provided, however, that the Certificated Securities presented or surrendered for
register of transfer or exchange:

               (3) shall be duly endorsed or accompanied by a written instrument
          of transfer in accordance with the fifth paragraph of Section 305 of
          the Indenture; and

               (4) in the case of a Restricted Certificated Security, such
          request shall be accompanied by the following additional information
          and documents, as applicable:

                    (A) if such Restricted Certificated Security is being
               delivered to the Registrar by a Holder for registration in the
               name of such Holder, without transfer, or such Restricted
               Certificated Security is being transferred to the Company or a
               Subsidiary of the Company, a certification to that effect from
               such Holder (in substantially the form set forth in the Transfer
               Certificate required pursuant to Section 102(e)(1) hereof); or

                    (B) if such Restricted Certificated Security is being
               transferred to a person the Holder reasonably believes is a QIB
               in accordance with Rule 144A or pursuant to an effective
               registration statement under the Securities Act, a certification
               to that effect from such Holder and the transferee (in
               substantially the form set forth in the Transfer Certificate); or

                    (C) if such Restricted Certificated Security is being
               transferred (i) pursuant to an exemption from the registration
               requirements of the Securities Act in accordance with Rule 144,
               (ii) pursuant to an exemption from the

                                      -4-
<PAGE>   7

               registration requirements of the Securities Act (other than
               pursuant to Rule 144A or Rule 144) and as a result of which, in
               the case of a Security transferred pursuant to this clause (ii),
               such Security shall cease to be a "restricted security" within
               the meaning of Rule 144, a certification to that effect from the
               Holder or (iii) pursuant to an exemption from the registration
               requirements of the Securities Act to a non-U.S. person in an
               offshore transaction under Regulation S under the Securities Act,
               a certification to that effect from the transferor (in
               substantially the form set forth in the Transfer Certificate),
               and, if the Company or such Registrar so requests, a customary
               opinion of counsel, certificates and other information reasonably
               acceptable to the Company and such Registrar to the effect that
               such transfer is in compliance with the Securities Act.

         (c) Transfer of a Beneficial Interest in a Restricted Global Security
for a Beneficial Interest in an Unrestricted Global Security. Any person having
a beneficial interest in a Restricted Global Security may upon request, subject
to the Applicable Procedures, transfer such beneficial interest to a person who
is required or permitted to take delivery thereof in the form of an Unrestricted
Global Security. Upon receipt by the Trustee of written instructions or such
other form of instructions and the following additional information and
documents, in each case in such form as is customary for the Depositary, from
the Depositary or its nominee on behalf of the person having such beneficial
interest in the Restricted Global Security (all of which may be submitted by
facsimile or electronically):

               (1) if such beneficial interest is being transferred pursuant to
          an effective registration statement under the Securities Act, a
          certification to that effect from the transferor (in substantially the
          form set forth in the Transfer Certificate); or

               (2) if such beneficial interest is being transferred (i) pursuant
          to an exemption from the registration requirements of the Securities
          Act in accordance with Rule 144 or (ii) pursuant to an exemption from
          the registration requirements of the Securities Act (other than
          pursuant to Rule 144A or Rule 144) and as a result of which, in the
          case of a Security transferred pursuant to this sub-clause (ii), such
          Security shall cease to be a "restricted security" within the meaning
          of Rule 144, a certification to that effect from the transferor (in
          substantially the form set forth in the Transfer Certificate) and, if
          the Company or the Trustee so requests, a customary opinion of
          counsel, certificates and other information reasonably acceptable to
          the Company and the Trustee to the effect that such transfer is in
          compliance with the Securities Act,

the Trustee, as a Registrar and Security Custodian, shall reduce or cause to be
reduced the aggregate Principal Amount of the Restricted Global Security by the
appropriate Principal Amount and shall increase or cause to be increased the
aggregate Principal Amount of the Unrestricted Global Security by a like
Principal Amount. Such transfer shall otherwise be effected in accordance with
the Applicable Procedures. If no Unrestricted Global Security is then
outstanding, the Company shall execute and the Trustee shall, upon receipt of a
Company Order (which the Company agrees to deliver promptly), authenticate and
deliver an Unrestricted Global Security.

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<PAGE>   8

         (d) Transfers of Certificated Securities for Beneficial Interest in
Global Securities. If Certificated Securities are issued in exchange for
beneficial interests in Global Securities and, thereafter, the events or
conditions specified in Section 102(a)(1) hereof which required such exchange
shall have ceased to exist, the Company shall mail notice to the Trustee and to
the Holders stating that Holders may exchange Certificated Securities for
interests in Global Securities by complying with the procedures set forth herein
and briefly describing such procedures and the events or circumstances requiring
that such notice be given. Thereafter, if Certificated Securities are presented
by a Holder to a Registrar with a request:

               (1) to register the transfer of such Certificated Securities to a
          person who will take delivery thereof in the form of a beneficial
          interest in a Global Security, which request shall specify whether
          such Global Security will be a Restricted Global Security or an
          Unrestricted Global Security; or

               (2) to exchange such Certificated Securities for an equal
          Principal Amount of beneficial interests in a Global Security, which
          beneficial interests will be owned by the Holder transferring such
          Certificated Securities (provided that in the case of such an
          exchange, Restricted Certificated Securities may be exchanged only for
          Restricted Global Securities and Unrestricted Certificated Securities
          may be exchanged only for Unrestricted Global Securities),

the Registrar shall register the transfer or make the exchange as requested by
canceling such Certificated Security and causing, or directing the Security
Custodian to cause, the aggregate Principal Amount of the applicable Global
Security to be increased accordingly and, if no such Global Security is then
outstanding, the Company shall issue and the Trustee shall, upon receipt of a
Company Order (which the Company agrees to deliver promptly), authenticate and
deliver a new Global Security; provided, however, that the Certificated
Securities presented or surrendered for registration of transfer or exchange:

               (3) shall be duly endorsed or accompanied by a written instrument
          of transfer in accordance with the fifth paragraph of Section 305 of
          the Indenture;

               (4) in the case of a Restricted Certificated Security to be
          transferred for a beneficial interest in an Unrestricted Global
          Security, such request shall be accompanied by the following
          additional information and documents, as applicable:

                    (A) if such Restricted Certificated Security is being
               transferred pursuant to an effective registration statement under
               the Securities Act, a certification to that effect from such
               Holder (in substantially the form set forth in the Transfer
               Certificate); or

                    (B) if such Restricted Certificated Security is being
               transferred pursuant to (i) an exemption from the registration
               requirements of the Securities Act in accordance with Rule 144 or
               (ii) pursuant to an exemption from the registration requirements
               of the Securities Act (other than pursuant to Rule 144A or Rule
               144) and as a result of which, in the case of a Security
               transferred pursuant to this clause (ii), such Security shall
               cease to be a "restricted security"

                                      -6-
<PAGE>   9

               within the meaning of Rule 144, a certification to that effect
               from such Holder, and, if the Company or the Registrar so
               requests, a customary opinion of counsel, certificates and other
               information reasonably acceptable to the Company and the Trustee
               to the effect that such transfer is in compliance with the
               Securities Act;

          (5) in the case of a Restricted Certificated Security to be
     transferred or exchanged for a beneficial interest in a Restricted Global
     Security, such request shall be accompanied by a certification from such
     Holder and, in the case of clause (i), the transferee (in substantially the
     form set forth in the Transfer Certificate) to the effect that such
     Restricted Certificated Security is being transferred to (i) a person the
     Holder reasonably believes is a QIB (which, in the case of an exchange,
     shall be such Holder) in accordance with Rule 144A or (ii) a non-U.S.
     person in an offshore transaction under Regulation S under the Securities
     Act; and

          (6) in the case of an Unrestricted Certificated Security to be
     transferred or exchanged for a beneficial interest in an Unrestricted
     Global Security, such request need not be accompanied by any additional
     information or documents.

     (e) Legends.

          (1) Except as permitted by the following paragraphs (2) and (3) of
     this Section 102(e), each Global Security and Certificated Security (and
     all Securities issued in exchange therefor or upon registration of transfer
     or replacement thereof and any Common Stock issuable upon conversion
     thereof) shall bear a legend in substantially the form called for by
     footnote 2 to Annex A hereto (each a "Transfer Restricted Security") for so
     long as such Security or Common Stock issuable upon conversion thereof is
     required by this Indenture to bear such legend. Each Transfer Restricted
     Security shall have attached thereto a certificate (a "Transfer
     Certificate") in substantially the form called for by footnote 6 to Annex A
     hereto.

          (2) Upon any sale or transfer of a Transfer Restricted Security (x)
     pursuant to Rule 144, (y) pursuant to an effective registration statement
     under the Securities Act or (z) pursuant to any other available exemption
     (other than Rule 144A) from the registration requirements of the Securities
     Act and as a result of which, in the case of a Security transferred
     pursuant to this clause (z), such Security shall cease to be a "restricted
     security" within the meaning of Rule 144:

               (A) in the case of any Restricted Certificated Security, any
          Registrar shall permit the Holder thereof to exchange such Restricted
          Certificated Security for an Unrestricted Certificated Security, or
          (under the circumstances described in Section 102(d) hereof) to
          transfer such Restricted Certificated Security to a transferee who
          shall take such Security in the form of a beneficial interest in an
          Unrestricted Global Security, and in each case shall rescind any
          restriction on the transfer of such Security; provided, however, that
          the Holder of such Restricted Certificated Security shall, in
          connection with such exchange or transfer, comply with the other
          applicable provisions of this Section 102; and

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<PAGE>   10

               (B) in the case of any beneficial interest in a Restricted Global
          Security, the Trustee shall permit the beneficial owner thereof to
          transfer such beneficial interest to a transferee who shall take such
          interest in the form of a beneficial interest in an Unrestricted
          Global Security and shall rescind any restriction on transfer of such
          beneficial interest; provided, however, that such Unrestricted Global
          Security shall continue to be subject to the provisions of Section
          102(a)(2) hereof; and provided further, however, that the owner of
          such beneficial interest shall, in connection with such transfer,
          comply with the other applicable provisions of this Section 102.

          (3) Upon the exchange, registration of transfer or replacement of
     Securities not bearing the legend described in paragraph (1) of this
     Section 102(e) above, the Company shall execute and the Trustee shall
     authenticate and deliver Securities that do not bear such legend and which
     do not have a Transfer Certificate attached thereto.

         (f) Transfers to the Company. Nothing in this Indenture or in the
Securities shall prohibit the sale or other transfer of any Securities
(including beneficial interests in Global Securities) to the Company or any of
its Subsidiaries, which Securities shall thereupon be canceled in accordance
with Section 309 of the Indenture.

Section 103 Amount.

         (a) The Trustee shall authenticate and deliver 2021 Debentures for
original issue in an aggregate Principal Amount of up to $1,766,500,000.00 upon
Company Order for the authentication and delivery of 2021 Debentures, without
any further action by the Company; provided, however, that if the Company sells
any Securities pursuant to the over-allotment option (the "Option") granted to
the Initial Purchaser pursuant to Section 3 of the Purchase Agreement, then the
Trustee shall authenticate and deliver Securities for original issue in an
aggregate Principal Amount of up to $1,766,500,000.00 plus up to an additional
aggregate Principal Amount of up to $441,625,000.00 of Securities sold pursuant
to the Option upon a Company Order. The aggregate Principal Amount of 2021
Debentures that may be authenticated and delivered under the Indenture may not
exceed the amount set forth in the foregoing sentence, except for 2021
Debentures authenticated and delivered (1) upon registration of transfer of, or
in exchange for, or in lieu of, other 2021 Debentures pursuant to Sections 204,
304, 305, 306, 906 and 1107, of the Indenture and Sections 1402, 1511 and 1604
hereof or (2) upon any reopening effected in accordance with the fourth
paragraph of Section 301 of the Indenture.

         (b) The Company may not issue new 2021 Debentures to replace 2021
Debentures that it has paid or delivered to the Trustee for cancellation or that
any Holder has converted pursuant to Article FOURTEEN hereof.

Section 104 Accrual of Original Issue Discount; Interest.

         The 2021 Debentures shall be Original Issue Discount Securities.
Original Issue Discount shall accrue with respect to the 2021 Debentures at the
rate set forth under the caption "Interest" in the 2021 Debentures, commencing
on the Issue Date of the 2021 Debentures. Except (a) as provided under the
caption "Tax Event" in the 2021 Debentures and in Article

                                      -8-
<PAGE>   11

SEVENTEEN hereof and (b) for Additional Interest that may become payable as
contemplated in Section 105 hereof, there shall be no periodic payments of
interest on the 2021 Debentures.

Section 105 Additional Interest.

         Additional Interest with respect to the 2021 Debentures shall be
payable in accordance with the provisions and in the amounts set forth in the
Section 5 of the Registration Rights Agreement.

Section 106 Denominations.

         The 2021 Debentures shall be in fully registered form without coupons
in denominations of $1,000 of Principal Amount or any integral multiple thereof.

Section 107 Place of Payment.

         The Place of Payment for the 2021 Debentures and the place or places
where the 2021 Debentures may be surrendered for registration of transfer,
exchange, repurchase, redemption or conversion and where notices may be given to
the Company in respect of the 2021 Debentures is at the office or agency of the
Trustee in New York, New York; provided, however, that payment of interest may
be made at the option of the Company by check mailed to the address of the
Person entitled thereto as such address shall appear in the Security Register
(as defined in the Indenture). Payments in respect of the 2021 Debentures
evidenced by a Global Security shall be made by transfer of immediately
available funds to the accounts specified by the Holder of the Global Security.

Section 108 Redemption.

         (a) There shall be no sinking fund for the retirement of the 2021
Debentures.

         (b) The Company, at its option, may redeem the 2021 Debentures in
accordance with the provisions of and at the Redemption Prices set forth under
the captions "Optional Redemption" and "Notice of Redemption" in the 2021
Debentures and in accordance with the provisions of the Indenture, including,
without limitation, Article ELEVEN.

Section 109 Conversion.

         The 2021 Debentures shall be convertible in accordance with the
provisions and at the Conversion Rate set forth under the caption "Conversion"
in the 2021 Debentures and in accordance with the provisions of the Indenture,
including, without limitation, Article FOURTEEN hereof.

Section 110 Maturity.

         The date on which the principal of the 2021 Debentures matures and is
payable, unless accelerated or required to be repurchased pursuant to the
Indenture, shall be February 28, 2021.

                                      -9-
<PAGE>   12

Section 111 Repurchase.

         (a) The 2021 Debentures shall be repurchased by the Company in
accordance with the provisions and at the Purchase Prices set forth under the
caption "Repurchase by the Company at the Option of the Holder" in the 2021
Debentures and in accordance with the provisions of the Indenture, including,
without limitation, Article FIFTEEN hereof.

         (b) The 2021 Debentures shall be repurchased by the Company in
accordance with the provisions of and at the Change in Control Purchase Prices
set forth under the caption "Purchase of Securities at Option of Holder Upon a
Change in Control" in the 2021 Debentures and in accordance with the provisions
of the Indenture, including, without limitation, Article SIXTEEN hereof.

Section 112 Covenants.

         The 2021 Debentures shall benefit from each of the covenants set forth
in Article TEN of the Indenture, including, without limitation, Sections 1006
("Limitations on Liens") and 1007 ("Limitations on Sale-Leaseback Transactions")
of the Indenture, and the related definitions set forth in Section 101 of the
Indenture.

Section 113 Amount Due Upon Event of Default.

         The portion of the Principal Amount of each 2021 Debenture that shall
become due pursuant to Section 502 of the Indenture in the circumstances
specified therein upon an Event of Default shall be the Issue Price plus accrued
Original Issue Discount on such 2021 Debentures (or, if the 2021 Debentures have
been converted to interest bearing 2021 Debentures pursuant to Section 1701, the
Restated Principal Amount and all accrued and unpaid interest thereon from the
later of the date of conversion and the date on which interest was last paid or
duly provided for).

Section 114 Discharge of Liability on 2021 Debentures.

         The 2021 Debentures may be discharged by the Company in accordance with
the provisions of Article THIRTEEN of the Indenture.

Section 115 Other Terms of 2021 Debentures.

         Without limiting the foregoing provisions of this Article I, the terms
of the 2021 Debentures shall be as set forth in the form of the 2021 Debentures
set forth in Annex A hereto and as provided in the Indenture.

                                      -10-
<PAGE>   13

                                   ARTICLE II

                           AMENDMENTS TO THE INDENTURE

Section 201       Amendments Applicable Only to 2021 Debentures.

         The amendments contained herein shall apply to the 2021 Debentures only
and not to any other series of Security issued under the Indenture and any
covenants provided herein are expressly being included solely for the benefit of
the 2021 Debentures and not for the benefit of any other series of Securities
issued under the Indenture. The amendments contained herein shall be effective
for so long as any 2021 Debentures remain Outstanding.

Section 202 Definitions.

         Section 101 of the Original Indenture is hereby amended, subject to
Section 201 hereof and with respect to the 2021 Debentures only, by inserting or
restating, as the case may be, in their appropriate alphabetical position, the
following definitions:

         "Additional Interest" shall have the meaning set forth in Section 5(a)
of the Registration Rights Agreement.

         "Agent Members" has the meaning specified in Section 101(b) hereof.

         "Applicable Procedures" means, with respect to any transfer or exchange
of beneficial ownership interests in a Global Security, the rules and procedures
of the Depositary that are applicable to such transfer or exchange.

         "Beneficial Owner" has the meaning specified in Section 1601(a) hereof.

         "Certificated Security" means a Security that is in substantially the
form attached hereto as Annex A and that does not include the information or the
schedule called for by footnotes 1, 4 and 5 thereof.

         "Change in Control" has the meaning specified in Section 1601(a)
hereof.

         "Change in Control Purchase Date" has the meaning specified in Section
1601(a) hereof.

         "Change in Control Purchase Notice" has the meaning specified in
Section 1601(c) hereof.

         "Change in Control Purchase Price" has the meaning specified in Section
1601(a) hereof.

         "Common Stock" means any stock of any class of the Company (including,
without limitation, the Company's common stock, par value $3.00 per share) which
has no preference in respect of dividends or of amounts payable in the event of
any voluntary or involuntary liquidation, dissolution or winding up of the
Company and which is not subject to redemption by the Company. References herein
or in the 2021 Debentures to a number of shares of Common

                                      -11-
<PAGE>   14

Stock shall include a reference to a corresponding number of preferred share
purchase rights issued under Rights Agreement.

         "Company Notice Date" has the meaning specified in Section 1503 hereof.

         "Conversion Agent" shall be the person designated as such in Section
101(c) hereof and, with respect to the 2021 Debentures, shall have the duties
and responsibilities specified in Article FOURTEEN hereof. The Company may
appoint such other Person(s) from time to time to serve as a Conversion Agent,
such appointment to be effected by notice delivered by the Company to the
Trustee.

         "Conversion Date" has the meaning specified in Section 1402 hereof.

         "Conversion Rate" has the meaning specified in Section 1401 hereof.

         "CSFB" has the meaning specified in Section 101(a) hereof.

         "Depositary" has the meaning specified in Section 101(a) hereof.

         "Determination Date" has the meaning specified in Section 1406(d)(1)
hereof.

         "DTC" has the meaning specified in Section 101 hereof.

         "Expiration Date" has the meaning specified in Section 1406(d)(2)
hereof.

         "Expiration Time" has the meaning specified in Section 1406(d)(2)
hereof.

         "Global Security" means a permanent Global Security that is in
substantially the form attached hereto as Annex A and that includes the
information and schedule called for by footnotes 1, 4 and 5 thereof and which is
deposited with the Depositary or the Security Custodian and registered in the
name of the Depositary or its nominee.

         "Group" has the meaning specified in Section 1601(a) hereof.

         "Indenture" has the meaning specified in the recitals.

         "Initial Purchaser" has the meaning specified in Section 101(a) hereof.

         "Issue Date" of any 2021 Debenture means the date on which the 2021
Debenture was originally issued or deemed issued as set forth on the face of the
2021 Debenture.

         "Issue Price" of any 2021 Debenture means, in connection with the
original issuance of such 2021 Debenture, the original initial issue price at
which the 2021 Debenture is sold as set forth on the face of the 2021 Debenture.

         "Market Price" has the meaning specified in Section 1504 hereof.

         "non-electing share" has the meaning specified in Section 1411 hereof.

                                      -12-
<PAGE>   15

         "NYSE" has the meaning specified in Section 1406(e) hereof.

         "Nasdaq" has the meaning set forth in Section 1406(e) hereof.

         "Option Exercise Date" has the meaning specified in Section 1701
hereof.

         "Original Issue Discount" of any 2021 Debenture means the difference
between the Issue Price and the Principal Amount of the 2021 Debenture as set
forth on the face of the 2021 Debenture.

         "Permitted Amount" has the meaning specified in Section 1406(d)(1) or
1406(d)(2), as the case may be.

         "Principal Amount" of a 2021 Debenture means the principal amount due
at the Stated Maturity of the 2021 Debentures as set forth on the face of the
2021 Debenture.

         "Purchase Agreement" means the Purchase Agreement, dated as of February
22, 2001, between the Company and Credit Suisse First Boston Corporation.

         "Purchased Shares" has the meaning specified in Section 1406(d)(2)
hereof.

         "QIB" has the meaning specified in Section 101 hereof.

         "Registration Rights Agreement" means the Registration Rights
Agreement, dated as of February 22, 2001, between the Company and Credit Suisse
First Boston Corporation.

         "Regulation S" means Regulation S of the rules and regulations
promulgated under the Securities Act or any successor to such Regulation.

         "Repurchase Date" has the meaning specified in Section 1501 hereof.

         "Repurchase Notice" has the meaning specified in Section 1501 hereof.

         "Repurchase Price" has the meaning specified in Section 1501 hereof.

         "Restated Principal Amount" has the meaning specified in Section 1701
hereof.

         "Restricted Certificated Security" means a Certificated Security which
is a Transfer Restricted Security.

         "Restricted Global Security" means a Global Security that is a Transfer
Restricted Security.

         "Rights Agreement" means the Amended and Restated Preferred Share
Purchase Rights Agreement, dated as of January 20, 1999, between the Company and
BankBoston, N.A., as rights agent, as same may be amended, modified or restated
while any of the 2021 Debentures remain outstanding.

                                      -13-
<PAGE>   16

         "Rule 144" means Rule 144 of the rules and regulations promulgated
under the Securities Act or any successor to such Rule.

         "Rule 144A" means Rule 144A of the rules and regulations promulgated
under the Securities Act or any successor to such Rule.

         "Sale Price" has the meaning specified in Section 1504 hereof.

         "Securities" means any securities authenticated and delivered under the
Indenture, as the same may be amended or supplemented, including 2021
Debentures.

         "Securities Act" means the Securities Act of 1933, as amended, or any
successor statute.

         "Tax Event" means that the Company shall have received an opinion from
independent tax counsel experienced in such matters to the effect that, on or
after February 28, 2001, as a result of (a) any amendment to, or change
(including any announced prospective change) in, the laws (or any regulations
thereunder) of the United States or any political subdivision or taxing
authority thereof or therein or (b) any amendment to, or change in, an
interpretation or application of such laws or regulations by any legislative
body, court, governmental agency or regulatory authority, in each case, which
amendment or change is enacted, promulgated, issued or announced or which
interpretation is issued or announced or which action is taken, on or after
February 28, 2001, there is more than an insubstantial risk that interest
(including Original Issue Discount) payable on the 2021 Debentures either (i)
would not be deductible on a current accrual basis or (ii) would not be
deductible under any other method, in either case, in whole or in part, by the
Company (by reason of deferral, disallowance or otherwise) for United States
Federal income tax purposes.

         "Tax Event Date" has the meaning specified in Section 1701 hereof.

         "tender offer" has the meaning specified in Section 1406(d)(3) hereof.

         "Trading Day" means a day during (i) which trading in securities
generally occurs on the NYSE or, if the Common Stock is not listed for trading
on the NYSE, on the principal other national or regional securities exchange on
which the Common Stock is then listed for trading or, if the Common Stock is not
listed for trading on a national or regional securities exchange, on the Nasdaq
or, if the Common Stock is not quoted on the Nasdaq, on the other principal
market on which the Common Stock is then traded and (ii) trading in the Common
Stock is not then suspended on the NYSE or such principal national or regional
securities exchange, Nasdaq or other principal market, as the case may be, on
which the Common Stock is then traded.

         "Transfer Certificate" has the meaning specified in Section 102(e)(1)
hereof.

         "Transfer Restricted Securities" has the meaning specified in Section
102(e)(1) hereof.

         "Trigger Event" has the meaning specified in Section 1406(c) hereof.

         "Triggering Distribution" has the meaning specified in Section
1406(d)(1) hereof.

                                      -14-
<PAGE>   17

         "2021 Debentures" has the meaning specified in the recitals.

         "Unrestricted Certificated Security" means a Certificated Security
which is not a Transfer Restricted Security.
         "Unrestricted Global Security" means a Global Security which is not a
Transfer Restricted Security.

Section 203       Definition of Outstanding.

         The Original Indenture is hereby amended, subject to Section 201 hereof
and with respect to the 2021 Debentures only, by (a) deleting "and" at the end
of clause (3) of the definition of the term "Outstanding" in Section 101 of the
Original Indenture, (b) deleting the period and inserting "; and" at the end of
clause (4) of the definition of the term "Outstanding" in Section 101 of the
Original Indenture and (c) inserting the following as clause (5) of the
definition of the term "Outstanding" in Section 101 of the Original Indenture:

               (5) 2021 Debentures that have been converted into Common Stock in
          accordance with Section 1402 hereof.

Section 204 Registration, Registration of Transfer and Exchange.

         The Original Indenture is hereby amended, subject to Section 201 hereof
and with respect to the 2021 Debentures only, by replacing the seventh paragraph
of Section 305 of the Original Indenture with the following paragraph:

         The Company shall not be required (i) to issue, register the transfer
         of or exchange the 2021 Debentures during a period beginning at the
         opening of business 15 days before the day of the mailing of a notice
         of redemption of 2021 Debentures selected for redemption and ending at
         the close of business on the day of such mailing, (ii) to register the
         transfer of or exchange any 2021 Debenture so selected for redemption
         in whole or in part, except the unredeemed portion of any Security
         being redeemed in part, or (iii) to exchange or register a transfer of
         any 2021 Debenture or portions thereof in respect of which a Change in
         Control Purchase Notice or Repurchase Notice has been delivered and not
         withdrawn by the Holder thereof (except, in the case of the purchase of
         a 2021 Debenture in part, the portion not to be purchased or which has
         been surrendered for conversion).

Section 205 Mutilated, Destroyed, Lost and Stolen Securities.

         The Original Indenture is hereby amended, subject to Section 201 hereof
and with respect to the 2021 Debentures only, by replacing the third paragraph
of Section 306 of the Original Indenture with the following paragraph:

         If any such mutilated, destroyed, lost or stolen Security constitutes a
         2021 Debenture that has or is about to become due and payable, or is
         about to be purchased by the Company on a Repurchase Date pursuant to
         Article FIFTEEN,

                                      -15-
<PAGE>   18

          or purchased by the Company upon a Change in Control pursuant to
          Article SIXTEEN, the Company in its discretion may, instead of issuing
          a new Security, pay such Security.

Section 206 Payment of Interest; Interest Rights Preserved.

         The Original Indenture is hereby amended, subject to Section 201 hereof
and with respect to the 2021 Debentures only, by inserting the following
paragraph as the second paragraph of Section 307 of the Original Indenture:

         If the Company exercises its option pursuant to Section 1701, then in
         the case of any 2021 Debenture or portion thereof which is surrendered
         for conversion after the close of business on the Regular Record Date
         immediately preceding any Interest Payment Date and prior to the
         opening of business on such next succeeding Interest Payment Date
         (unless such 2021 Debenture or portion thereof which is being
         surrendered for conversion has been called for redemption on a
         Redemption Date within such period), interest whose Stated Maturity is
         on such Interest Payment Date shall be payable on such Interest Payment
         Date notwithstanding such conversion, and such interest (whether or not
         punctually paid or duly provided for) shall be paid to the Person in
         whose name that 2021 Debenture (or one or more Predecessor Securities)
         is registered at the close of business on such Regular Record Date;
         provided, however, that such payment of interest shall be subject to
         the payment to the Company by the Holder of such 2021 Debenture or
         portion thereof surrendered for conversion (such payment to accompany
         such surrender) of an amount equal to the amount of such interest, in
         accordance with Section 1402. Except as otherwise provided in the
         immediately preceding sentence, in the case of any 2021 Debenture which
         is converted, interest whose Stated Maturity is after the date of
         conversion of such 2021 Debenture shall not be payable.

Section 207 Cancellation.

         The Original Indenture is hereby amended, subject to Section 201 hereof
and with respect to the 2021 Debentures only, by inserting "conversion," after
"redemption," in the first sentence of Section 309 of the Original Indenture.

Section 208 Redemption.

         (a) Article ELEVEN of the Original Indenture is hereby amended, subject
to Section 201 hereof and with respect to the 2021 Debentures only, by (1)
replacing "30" in Section 1104 with "15" and (2) deleting and "at the end of
clause (5) of the second paragraph of Section 1104, deleting the period at the
end of clause (6) of such second paragraph and inserting ", and" in its place
and inserting the following as clause (7) of such second paragraph:

               (7) the Conversion Rate and the last date on which 2021
          Debentures may be surrendered for conversion prior to redemption.

                                      -16-
<PAGE>   19

         (b) Article ELEVEN of the Original Indenture is hereby amended, subject
to Section 201 hereof and with respect to the 2021 Debentures only, by inserting
the following as Section 1108:

                                      -17-
<PAGE>   20

         Section 1108 Conversion Arrangement on Call for Redemption.

         In connection with 2021 Debentures, the Company may arrange for the
         purchase and conversion of any 2021 Debentures called for redemption by
         an agreement with one or more investment bankers or other purchasers to
         purchase such 2021 Debentures by paying to a Paying Agent (other than
         the Company or any of its Affiliates) in trust for the Holders, on or
         before 11:00 a.m. New York City time on the Redemption Date, an amount
         that, together with any amounts deposited with such Paying Agent by the
         Company for the redemption of such 2021 Debentures, is not less than
         the Redemption Price of such 2021 Debentures. Notwithstanding anything
         to the contrary contained in this Article ELEVEN, the obligation of the
         Company to pay the Redemption Price of such 2021 Debentures, including
         interest, if any, shall be deemed to be satisfied and discharged to the
         extent such amount is so paid by such purchasers; provided, however,
         that nothing in this Section 1108 shall relieve the Company of its
         obligation to pay the Redemption Price on 2021 Debentures called for
         redemption. If such an agreement is entered into, any 2021 Debentures
         called for redemption and not surrendered for conversion by the Holders
         thereof prior to the relevant Redemption Date may, at the option of the
         Company upon written notice to the Trustee, be deemed, to the fullest
         extent permitted by law, acquired by such purchasers from such Holders
         and (notwithstanding anything to the contrary contained in Article
         ELEVEN) surrendered by such purchasers for conversion, all as of 11:00
         a.m. New York City time on the Redemption Date, subject to payment of
         the above amount as aforesaid. The Paying Agent shall hold and pay to
         the Holders whose 2021 Debentures are selected for redemption any such
         amount paid to it for purchase in the same manner as it would money
         deposited with it by the Company for the redemption of 2021 Debentures.
         Without the Paying Agent's prior written consent, no arrangement
         between the Company and such purchasers for the purchase and conversion
         of any 2021 Debentures shall increase or otherwise affect any of the
         powers, duties, responsibilities or obligations of the Paying Agent as
         set forth in this Indenture, and the Company agrees to indemnify the
         Paying Agent from, and hold it harmless against, any loss, liability or
         expense arising out of or in connection with any such arrangement for
         the purchase and conversion of any 2021 Debentures between the Company
         and such purchasers, including, without limitation, the costs and
         expenses incurred by the Paying Agent in the defense of any claim or
         liability reasonably incurred without negligence or bad faith on its
         part arising out of or in connection with the exercise or performance
         of any of its powers, duties, responsibilities or obligations under
         this Indenture, in accordance with the indemnity provisions applicable
         to the Trustee set forth herein.

Section 209 Consolidation, Merger and Sale.

         Section 801 of the Original Indenture is hereby amended, subject to
Section 201 hereof and with respect to the 2021 Debentures only, by replacing
clause (1) of such Section 801 with the following:

                                      -18-
<PAGE>   21

                  (1) (A) in the case of a merger, the Company is the surviving
         entity, or (B) the Person formed by such consolidation or into which
         the Company is merged or the Person which acquires by sale or transfer,
         or which leases, the properties and assets of the Company as, or
         substantially as, an entirety shall expressly assume, by an indenture
         supplemental hereto, executed and delivered to the Trustee, in form
         reasonably satisfactory to the Trustee, the due and punctual payment of
         the principal of and any premium and interest on, and Additional
         Interest with respect to, all the Securities and the performance or
         observance of every covenant and condition of this Indenture on the
         part of the Company to be performed or observed and shall have
         expressly provided for conversion rights in accordance with Section
         1411.

Section 210 Defaults and Remedies.

         Section 501 of the Original Indenture is hereby amended, subject to
Section 201 hereof and with respect to the 2021 Debentures only, by deleting
subsections (1) and (2), and inserting instead the following as new subsections
(1) and (2) thereof:

                  (1) the Company defaults in the payment of any interest upon
         any 2021 Debenture, when it becomes due and payable, after conversion
         of the 2021 Debentures to interest bearing debentures pursuant to
         Section 1701, or in any payment of Additional Interest when it becomes
         due and payable, and the continuance of any such default for a period
         of 30 days; or

                  (2) the Company defaults in the payment of the Principal
         Amount (or, if the 2021 Debentures have been converted to
         interest-bearing 2021 Debentures pursuant to Section 1701, the Restated
         Principal Amount), the Issue Price plus accrued Original Issue
         Discount, the Redemption Price, the Repurchase Price or the Change in
         Control Purchase Price of any 2021 Debenture when the same becomes due
         and payable; or

Section 211 Collection of Indebtedness and Suits for Enforcement by Trustee.

         Section 503 of the Original Indenture is hereby amended, subject to
Section 201 hereof and with respect to the 2021 Debentures only, by deleting
subsections (1) and (2) of the first paragraph, and inserting instead the
following as new subsections (1) and (2) thereof:

                  (1) the Company defaults in the payment of any interest upon
         any 2021 Debentures, when it becomes due and payable, after conversion
         of the 2021 Debentures to interest bearing debentures pursuant to
         Section 1701, or in any payment of Additional Interest when it becomes
         due and payable, and the continuance of any such default for a period
         of 30 days, or

                  (2) the Company defaults in the payment of the Principal
         Amount (or, if the 2021 Debentures have been converted to
         interest-bearing 2021 Debentures pursuant to Section 1701, the Restated
         Principal Amount), the Issue Price plus accrued Original Issue
         Discount, the Redemption Price, the Repurchase Price or

                                      -19-
<PAGE>   22

          the Change in Control Purchase Price of any 2021 Debentures when the
          same becomes due and payable,

Section 212 Unconditional Right of Holders to Receive Principal, Premium and
Interest.

         Section 508 of the Original Indenture is hereby amended, subject to
Section 201 hereof and with respect to the 2021 Debentures only, by replacing
that Section with the following:

         SECTION 508 Rights of Holders to Receive Payment.

         Notwithstanding any other provision in this Indenture, the right of any
         Holder of a Security to receive payment of the principal of and
         (subject to Sections 307 and 1701) interest on such Security on or
         after the respective due dates expressed in such Security (or in the
         case of redemption, to receive the Redemption Price on the Redemption
         Date, in the case of a repurchase, to receive the Repurchase Price on
         the Repurchase Date, or in the case of a Change in Control, to receive
         the Change in Control Purchase Price on the Change in Control Purchase
         Date), or to institute suit for the enforcement of any such payment on
         or after such respective dates, is absolute and unconditional and shall
         not be impaired without the consent of the Holder.

Section 213 Supplemental Indentures Without Consent of Holders.

         Section 901 of the Original Indenture is hereby amended, subject to
Section 201 hereof and with respect to the 2021 Debentures only, by deleting
"or" at the end of clause (7) of Section 901, by deleting the period and
inserting "; or" at the end of clause (8) and by inserting the following
paragraph as clause (9) of Section 901:

               (9) to make provision with respect to the conversion rights, if
          any, to Holders of 2021 Debentures pursuant to the requirements of
          Article FOURTEEN hereof.

Section 214 Supplemental Indenture with Consent of Holder.

         Section 902 of the Original Indenture is hereby amended, subject to
Section 201 hereof and with respect to the 2021 Debentures only, by deleting
"or" at the end of clause (3) of Section 902, by deleting the period and
inserting "; or" at the end of clause (4) of Section 902 and by inserting the
following as clause (5) of Section 902:

               (5) adversely affect the right to convert any 2021 Debenture as
          provided in Article FOURTEEN, or adversely affect the right to require
          the Company to repurchase the 2021 Debentures as provided in Article
          FIFTEEN or Article SIXTEEN.

                                      -20-
<PAGE>   23

Section 215 Maintenance of Office or Agency.

         The Original Indenture is hereby amended, subject to Section 201 hereof
and with respect to the 2021 Debentures only, by inserting "or conversion" after
"payment" in the first sentence of Section 1002 of the Original Indenture.

Section 216 Conversion, Tax Event, Repurchase.

         The Original Indenture is hereby amended, subject to Section 201 hereof
and with respect to the 2021 Debentures only, by adding the following Articles
FOURTEEN, FIFTEEN, SIXTEEN and SEVENTEEN to the Original Indenture:

                                ARTICLE FOURTEEN
                                   CONVERSION

         Section 1401 Conversion Privilege.

                  (a) The 2021 Debentures shall be convertible in accordance
         with their terms and in accordance with this Article FOURTEEN.

                  (b) A Holder of a 2021 Debenture may convert the Principal
         Amount of such 2021 Debenture (or any portion thereof equal to a
         Principal Amount of $1,000 or any integral multiple of a Principal
         Amount of $1,000 in excess thereof) into Common Stock, at any time
         prior to the close of business on the date specified in the 2021
         Debentures, at the Conversion Rate then in effect. In case a 2021
         Debenture or portion thereof is called for redemption pursuant to
         Article ELEVEN, such conversion right shall terminate at the close of
         business on the Business Day immediately preceding the Redemption Date
         for such 2021 Debenture or such earlier date as the Holder presents
         such 2021 Debenture for redemption (unless the Company shall default in
         making the redemption payment when due, in which case the conversion
         right shall terminate at the close of business on the date such default
         is cured and such 2021 Debenture is redeemed). The number of shares of
         Common Stock issuable upon conversion of a 2021 Debenture per $1,000 of
         Principal Amount thereof (the "Conversion Rate") shall be that number
         set forth under "Conversion" in the 2021 Debentures, subject to
         adjustment as herein set forth. Provisions of this Indenture that apply
         to conversion of all of a 2021 Debenture also apply to conversion of a
         portion of a 2021 Debenture.

                  (c) A 2021 Debenture in respect of which a Holder has
         delivered a Repurchase Notice or Change in Control Purchase Notice
         exercising the option of such Holder to require the Company to purchase
         such 2021 Debenture, may be converted only if such notice of exercise
         is withdrawn in accordance with the terms of this Indenture. A Holder
         of 2021 Debentures is not entitled to any rights of a holder of Common
         Stock until such Holder has converted its 2021 Debentures to Common
         Stock, and only to the extent such 2021 Debentures are

                                      -21-
<PAGE>   24

         deemed to have been converted into Common Stock pursuant to this
         Article FOURTEEN.

         SECTION 1402 Conversion Procedure.

         To convert a 2021 Debenture, a Holder must (a) complete and manually
         sign the conversion notice on the back of the 2021 Debenture and
         deliver such notice to a Conversion Agent, (b) surrender the 2021
         Debenture to a Conversion Agent, (c) furnish appropriate endorsements
         and transfer documents if required by the Security Registrar or a
         Conversion Agent, and (d) pay any transfer or similar tax, if required.
         The date on which the Holder satisfies all of those requirements is the
         "Conversion Date." As soon as practicable after the Conversion Date,
         the Company shall deliver to the Holder through a Conversion Agent a
         certificate for the number of whole shares of Common Stock issuable
         upon the conversion and cash in lieu of any fractional shares pursuant
         to Section 1403. Anything herein to the contrary notwithstanding, in
         the case of Global Securities, conversion notices may be delivered and
         such 2021 Debentures may be surrendered for conversion in accordance
         with the applicable procedures of the Depositary as in effect from time
         to time. The Person in whose name the Common Stock certificate is
         registered shall be deemed to be a stockholder of record on the
         Conversion Date; provided, however, that no surrender of a 2021
         Debenture on any date when the stock transfer books of the Company
         shall be closed shall be effective to constitute the Person or Persons
         entitled to receive the shares of Common Stock upon such conversion as
         the record holder or holders of such shares of Common Stock on such
         date, but such surrender shall be effective to constitute the Person or
         Persons entitled to receive such shares of Common Stock as the record
         holder or holders thereof for all purposes at the close of business on
         the next succeeding day on which such stock transfer books are open;
         provided further, however, that such conversion shall be at the
         Conversion Rate in effect on the date that such 2021 Debenture shall
         have been surrendered for conversion, as if the stock transfer books of
         the Company had not been closed. Upon conversion of a 2021 Debenture,
         such Person shall no longer be a Holder of the 2021 Debenture so
         converted.

         No payment or adjustment will be made for dividends on, or other
         distributions with respect to, any Common Stock except as provided in
         this Article FOURTEEN. On conversion of a 2021 Debenture, that portion
         of accrued Original Issue Discount (and unpaid interest, if the Company
         has exercised its option provided for in Section 1701 hereof)
         attributable to the period from the Issue Date (or, in the case of
         interest, if the Company has exercised the option provided for in
         Section 1701 hereof, the later of (x) the Option Exercise Date and (y)
         the date on which interest was last paid or duly provided for) of the
         2021 Debenture through the Conversion Date with respect to the
         converted 2021 Debenture shall not be cancelled, extinguished or
         forfeited, but rather shall be deemed to be paid in full to the Holder
         thereof through delivery of the Common Stock (together with the cash
         payment, if any, in lieu of fractional shares) in exchange for the 2021
         Debenture being converted pursuant to the provisions

                                      -22-
<PAGE>   25

         hereof; and the fair market value of such shares of Common Stock
         (together with any such cash payment in lieu of fractional shares)
         shall be treated as issued, to the extent thereof, first in exchange
         for Original Issue Discount (and unpaid interest, if the Company has
         exercised its option provided for in Section 1701 hereof) accrued
         through the Conversion Date, and the balance, if any, of such fair
         market value of such Common Stock (and any such cash payment) shall be
         treated as issued in exchange for the Issue Price (or Restated
         Principal Amount, if the Company has exercised its option provided for
         in Section 1701) of the 2021 Debenture being converted pursuant to the
         provisions hereof. Each whole share of Common Stock issued upon
         conversion of any 2021 Debenture shall be accompanied by a preferre
         share purchase right issued under the Rights Agreement, if the Rights
         Agreement is then in effect notwithstanding the occurrence of any
         event that, under the terms of the Rights Agreements, results in the
         separation of rights from the Common Stock.

         If a Holder converts more than one 2021 Debenture at the same time, the
         number of shares of Common Stock issuable upon the conversion shall be
         based on the aggregate Principal Amount of 2021 Debentures so
         converted.

         Upon surrender of a 2021 Debenture that is converted in part, the
         Company shall execute, and the Trustee shall authenticate and deliver
         to the Holder, a new 2021 Debenture equal in Principal Amount to the
         Principal Amount of the unconverted portion of the 2021 Debenture
         surrendered.

         If the Company has exercised its option under Section 1701, 2021
         Debentures or portions thereof surrendered for conversion during the
         period from the close of business on any Regular Record Date
         immediately preceding any Interest Payment Date to the opening of
         business on such Interest Payment Date shall (unless such 2021
         Debentures or portions thereof have been called for redemption on a
         Redemption Date within such period) be accompanied by payment to the
         Company or its order, in New York Clearing House funds or other funds
         acceptable to the Company, of an amount equal to the interest payable
         on such Interest Payment Date on the principal amount of 2021
         Debentures or portions thereof being surrendered for conversion.

         SECTION 1403 Fractional Shares.

         The Company will not issue fractional shares of Common Stock upon
         conversion of 2021 Debentures. In lieu of such fractional shares, the
         Company will pay an amount in cash based upon the closing price
         (determined as provided in Section 1406(e)) of the Common Stock on the
         Trading Day immediately prior to the Conversion Date.

         SECTION 1404 Taxes on Conversion.

         If a Holder converts a 2021 Debenture, the Company shall pay any
         documentary, stamp or similar issue or transfer tax due on the issue of
         shares of Common Stock

                                      -23-
<PAGE>   26

         upon such conversion. However, the Holder shall pay any such tax which
         is due because the Holder requests the shares to be issued in a name
         other than the Holder's name. The Conversion Agent may refuse to
         deliver the certificate representing the Common Stock being issued in
         a name other than the Holder's name until the Conversion Agent
         receives a sum sufficient to pay any tax which will be due because the
         shares are to be issued in a name other than the Holder's name.
         Nothing herein shall preclude any tax withholding required by law or
         regulation.

         SECTION 1405 Company to Provide Common Stock.

         The Company shall, prior to issuance of any 2021 Debentures under this
         Indenture, and from time to time as may be necessary, reserve, out of
         its authorized but unissued Common Stock, a sufficient number of shares
         of Common Stock to permit the conversion of all 2021 Debentures
         Outstanding into shares of Common Stock. All shares of Common Stock
         delivered upon conversion of the 2021 Debentures shall be duly
         authorized, validly issued, fully paid and nonassessable and shall be
         free from preemptive rights and free of any Lien or adverse claim.

         The Company will endeavor promptly to comply with all federal and state
         securities laws regulating the registration of the offer, issuance and
         delivery of shares of Common Stock to a converting Holder upon
         conversion of 2021 Debentures, if any, and will list or cause to have
         quoted such shares of Common Stock on each national securities exchange
         or on the Nasdaq National Market or other over-the-counter market or
         such other market on which the shares of Common Stock are then listed
         or quoted.

         SECTION 1406 Adjustment of Conversion Rate.

         The Conversion Rate shall be adjusted from time to time by the Company
as follows:

                  (a) If the Company shall (i) pay a dividend on its Common
         Stock in shares of Common Stock, (ii) make a distribution on its Common
         Stock in shares of Common Stock, (iii) subdivide its outstanding Common
         Stock into a greater number of shares, or (iv) combine its outstanding
         Common Stock into a smaller number of shares, the Conversion Rate in
         effect immediately prior thereto shall be adjusted so that the Holder
         of any 2021 Debenture thereafter surrendered for conversion shall be
         entitled to receive that number of shares of Common Stock which it
         would have owned had such 2021 Debenture been converted immediately
         prior to the happening of such event. An adjustment made pursuant to
         this subsection (a) shall become effective immediately after the record
         date in the case of a dividend or distribution and shall become
         effective immediately after the effective date in the case of
         subdivision or combination.

                                      -24-
<PAGE>   27

                  (b) If the Company shall issue rights or warrants to all or
         substantially all holders of its Common Stock entitling them (for a
         period commencing no earlier than the record date described below and
         expiring not more than 60 days after such record date) to subscribe for
         or purchase shares of Common Stock (or securities convertible into
         Common Stock) at a price per share (or having a conversion price per
         share) less than the current market price per share of Common Stock (as
         determined in accordance with Section 1406(e)) on the record date for
         the determination of stockholders entitled to receive such rights or
         warrants, the Conversion Rate in effect immediately prior thereto shall
         be adjusted so that the same shall equal the rate determined by
         multiplying the Conversion Rate in effect immediately prior to such
         record date by a fraction, of which the numerator shall be the number
         of shares of Common Stock outstanding on such record date plus the
         number of additional shares of Common Stock offered (or into which the
         convertible securities so offered are convertible), and of which the
         denominator shall be the number of shares of Common Stock outstanding
         on such record date plus the number of shares which the aggregate
         offering price of the total number of shares of Common Stock so offered
         (or the aggregate conversion price of the convertible securities so
         offered, which shall be determined by multiplying the number of shares
         of Common Stock issuable upon conversion of such convertible securities
         by the conversion price per share of Common Stock pursuant to the terms
         of such convertible securities) would purchase at the current market
         price per share (as determined in accordance with Section 1406(e)) of
         Common Stock on such record date. Such adjustment shall be made
         successively whenever any such rights or warrants are issued, and shall
         become effective immediately after such record date. If at the end of
         the period during which such rights or warrants are exercisable not all
         rights or warrants shall have been exercised, the adjusted Conversion
         Rate shall be immediately readjusted to what it would have been based
         upon the number of additional shares of Common Stock actually issued
         (or the number of shares of Common Stock issuable upon conversion of
         convertible securities actually issued).

                  (c) If the Company shall (by dividend or otherwise) distribute
         to all or substantially all holders of its Common Stock any shares of
         capital stock (other than dividends or distributions of Common Stock on
         Common Stock to which Section 1406(a) applies) of the Company,
         evidences of indebtedness or other assets (including securities of any
         Person other than the Company, but excluding all-cash distributions or
         any distribution of rights or warrants referred to in 1406(b), any of
         the foregoing in respect of which an adjustment would be made pursuant
         to this Section 1406(c) and referred to as the "Described Securities"),
         then in each such case (unless the Company elects to reserve Described
         Securities for distribution to Holders of 2021 Debentures upon
         conversion of same so that any such Holder would receive upon such
         conversion, in addition to the shares of Common Stock (and cash in lieu
         of fractional shares, if any) to which such Holder is entitled, the
         amount and kind of Described Securities that such Holder would have
         received if such Holder had converted its 2021 Debenture(s) into Common
         Stock immediately prior to the record date for distribution of the
         Described Securities) the Conversion Rate shall be adjusted so that the
         same shall equal the

                                      -25-
<PAGE>   28

         rate determined by multiplying the current Conversion Rate by a
         fraction, of which the numerator shall be the current market price per
         share (as determined in accordance with Section 1406(e)) of the Common
         Stock on the record date referred to below, and of which the
         denominator shall be the current market price per share (as determined
         in accordance with Section 1406(e)) of the Common Stock on such record
         date less the fair market value on such record date (as determined by
         the Board of Directors, whose determination shall be conclusive
         evidence absent manifest error of such fair market value and which
         shall be evidenced by an Officer's Certificate delivered to the
         Trustee) of the portion of the Described Securities so distributed or
         of such rights or warrants applicable to one share of Common Stock
         (determined on the basis of the number of shares of Common Stock
         outstanding on the record date); provided, however, that if the then
         fair market value (as so determined) of the portion of the Described
         Securities so distributed applicable to one share of Common Stock is
         equal to or greater than the current market price (determined as
         aforesaid) of the Common Stock on the record date referred to below,
         in lieu of the foregoing adjustment, adequate provision shall be made
         so that each Holder of 2021 Debentures shall have the right to receive
         upon conversion the amount of Described Securities such Holder would
         have received had such Holder converted each 2021 Debenture on such
         Record Date. Such adjustment shall be made successively whenever any
         such distribution is made and shall become effective immediately after
         the record date for the determination of stockholders entitled to
         receive such distribution.

         If the Rights Agreement expires or is terminated and, while any of the
         2021 Debentures remain Outstanding, the Company implements another
         shareholder rights plan, such rights plan shall provide, subject to
         customary exceptions and limitations, that in lieu of making an
         adjustment of the Conversion Rate pursuant to this Section 1406(c) in
         respect of rights distributed under such other shareholder rights plan,
         upon conversion of the 2021 Debentures the Holders will receive, in
         addition to the Common Stock issuable upon such conversion, the rights
         issued under such rights plan (notwithstanding the occurrence of an
         event causing such rights to separate from the Common Stock at or prior
         to the time of conversion). Any distribution of rights or warrants
         pursuant to a shareholder rights plan complying with the requirements
         set forth in the immediately preceding sentence of this paragraph shall
         not constitute a distribution of rights or warrants for which an
         adjustment is to be made pursuant to this Section 1406(c).

         Rights or warrants distributed after the date hereof by the Company to
         all holders of Common Stock entitling the holders thereof to subscribe
         for or purchase shares of the Company's capital stock (either initially
         or under certain circumstances), which rights or warrants, until the
         occurrence of a specified event or events ("Trigger Event"): (i) are
         deemed to be transferred with such shares of Common Stock; (ii) are not
         exercisable; and (iii) are also issued in respect of future issuances
         of Common Stock, shall be deemed not to have been distributed for
         purposes of this Section 1406(c) (and no adjustment to the Conversion
         Rate under this Section 1406(c) will be required) until the occurrence
         of the earliest Trigger Event. If such right or warrant is subject to
         subsequent events, upon the

                                      -26-
<PAGE>   29

         occurrence of which such right or warrant shall become exercisable to
         purchase different securities, evidences of indebtedness or other
         assets or entitle the holder to purchase a different number or amount
         of the foregoing or to purchase any of the foregoing at a different
         purchase price, then the occurrence of each such event shall be deemed
         to be the date of issuance and record date with respect to a new right
         or warrant (and a termination or expiration of the existing right or
         warrant without exercise by the holder thereof). In addition, if (1)
         any distribution (or deemed distribution) of rights or warrants, or
         any Trigger Event or other event (of the type described in the
         preceding sentence) with respect thereto, resulted in an adjustment to
         the Conversion Rate under this Section 1406(c) and (2)(A) all such
         rights or warrants shall thereafter have been redeemed or repurchased
         without exercise by any holders thereof, then the Conversion Rate
         shall be readjusted upon such final redemption or repurchase to give
         effect to such distribution or Trigger Event, as the case may be, as
         though it were a cash distribution, equal to the per share redemption
         or repurchase price received by a holder of Common Stock with respect
         to such rights or warrants (assuming such holder had retained such
         rights or warrants), made to all holders of Common Stock as of the
         date of such redemption or repurchase, or (2) all of such rights or
         warrants shall thereafter have expired or been terminated without
         exercise, the Conversion Rate shall be readjusted as if such rights
         and warrants had never been issued.

                  (d) (1) If the Company shall, by dividend or otherwise, at any
         time distribute (a "Triggering Distribution") to all or substantially
         all holders of its Common Stock all-cash distributions in an aggregate
         amount that, together with the aggregate sum of (A) any cash and the
         fair market value (as determined by the Board of Directors, whose
         determination shall be conclusive evidence thereof and which shall be
         evidenced by an Officer's Certificate delivered to the Trustee) of any
         other consideration payable in respect of any tender offer (other than
         an odd-lot offer) by the Company or a Subsidiary of the Company for
         Common Stock consummated within the 12 months preceding the date of
         payment of the Triggering Distribution and in respect of which no
         Conversion Rate adjustment pursuant to this Section 1406 has been made
         and (B) all other cash distributions to all or substantially all
         holders of its Common Stock made within the 12 months preceding the
         date of payment of the Triggering Distribution and in respect of which
         no Conversion Rate adjustment pursuant to this Section 1406 has been
         made, exceeds an amount equal to 12.5% of the product (the amount of
         such product, the "Permitted Amount") of (I) the current market price
         per share of Common Stock (as determined in accordance with Section
         1406(e)) on the Business Day (the "Determination Date") immediately
         preceding the day on which such Triggering Distribution is declared by
         the Company multiplied by (III) the number of shares of Common Stock
         outstanding on the Determination Date (excluding shares held in the
         treasury of the Company), then, immediately prior to the opening of
         business on the day following the date on which the Triggering
         Distribution is paid, the Conversion Rate shall be increased so that
         the same shall equal the rate determined by multiplying such Conversion
         Rate in effect immediately prior to the Determination Date by a
         fraction, of which the numerator shall be such current market price per
         share of Common Stock (as determined in accordance with Section
         1406(e)) on the Determination Date, and of which the denominator shall
         be the current market price per share of Common Stock (as

                                      -27-
<PAGE>   30

         determined in accordance with Section 1406(e)) on the Determination
         Date less the sum of the aggregate amount of cash and the aggregate
         fair market value (determined as aforesaid) of any such other
         consideration so distributed, paid or payable within such 12 months
         (including, without limitation, the Triggering Distribution)
         applicable to one share of Common Stock (determined on the basis of
         the number of shares of Common Stock outstanding on the Determination
         Date) (such amount, the "Adjustment Amount"); provided, however, that
         if the Adjustment Amount is equal to or greater than the current
         market price (determined in accordance with Section 1406(e)) of the
         Common Stock on the Determination Date, in lieu of the foregoing
         adjustment to the Conversion Rate, adequate provision shall be made so
         that each Holder of 2021 Debentures shall have the right to receive
         upon conversion the amount of cash such Holder would have received had
         such Holder converted each 2021 Debenture on the record date for such
         distribution.

                  (2) If any tender offer (other than an odd-lot offer) made by
         the Company or any of its Subsidiaries for Common Stock shall expire
         and such tender offer (as amended upon the expiration thereof) shall
         involve the payment of aggregate consideration in an amount (determined
         as the sum of the aggregate amount of cash consideration and the
         aggregate fair market value (as determined by the Board of Directors,
         whose determination shall be conclusive evidence thereof and which
         shall be evidenced by an Officer's Certificate delivered to the Trustee
         thereof ) of any other consideration) that, together with the aggregate
         sum of (A) any cash and the fair market value (as determined by the
         Board of Directors, whose determination shall be conclusive evidence
         thereof and which shall be evidenced by an Officer's Certificate
         delivered to the Trustee) of any other consideration payable in respect
         of any other tender offers (other than an odd-lot offer(s)) by the
         Company or any Subsidiary of the Company for Common Stock consummated
         within the 12 months preceding the Expiration Date (as defined below)
         and in respect of which no Conversion Rate adjustment pursuant to this
         Section 1406 has been made and (B) all cash distributions to all or
         substantially all holders of its Common Stock made within the 12 months
         preceding the Expiration Date and in respect of which no Conversion
         Rate adjustment pursuant to this Section 1406 has been made, exceeds an
         amount equal to 12.5% of the product (the amount of such product, the
         "Permitted Amount") of the current market price per share of Common
         Stock (as determined in accordance with Section 1406(e)) as of the last
         date (the "Expiration Date") tenders could have been made pursuant to
         such tender offer (as it may be amended) (the last time at which such
         tenders could have been made on the Expiration Date is hereinafter
         sometimes called the "Expiration Time") multiplied by the number of
         shares of Common Stock outstanding (including tendered shares but
         excluding any shares held in the treasury of the Company) at the
         Expiration Time, then, immediately prior to the opening of business on
         the day after the Expiration Date, the Conversion Rate shall be
         increased so that the same shall equal the rate determined by
         multiplying the Conversion Rate in effect immediately prior to the

                                      -28-
<PAGE>   31

         close of business on the Expiration Date by a fraction, of which the
         numerator shall be the sum of (x) the aggregate consideration
         (determined as aforesaid) payable to stockholders based on the
         acceptance (up to any maximum specified in the terms of the tender
         offer) of all shares validly tendered and not withdrawn as of the
         Expiration Time (the shares deemed so accepted, up to any such maximum,
         being referred to as the "Purchased Shares") and (y) the product of the
         number of shares of Common Stock outstanding (excluding any Purchased
         Shares and any shares held in the treasury of the Company) at the
         Expiration Time and the current market price per share of Common Stock
         (as determined in accordance with Section 1406(e)) on the Trading Day
         next succeeding the Expiration Date, and of which the denominator shall
         be the product of the number of shares of Common Stock outstanding
         (including tendered shares but excluding any shares held in the
         treasury of the Company) at the Expiration Time multiplied by the
         current market price per share of Common Stock (as determined in
         accordance with Section 1406(e)) on the Trading Day next succeeding the
         Expiration Date, such increase to become effective immediately prior to
         the opening of business on the day following the Expiration Date. If
         the Company is obligated to purchase shares pursuant to any such tender
         offer, but the Company is permanently prevented by applicable law from
         effecting any or all such purchases or any or all such purchases are
         rescinded, the Conversion Rate shall again be adjusted to be the
         Conversion Rate which would have been in effect based upon the number
         of shares actually purchased. If the application of this Section
         1406(d)(2) to any tender offer would result in a decrease in the
         Conversion Rate, no adjustment shall be made for such tender offer
         under this Section 1406(d)(2).

                  (3) For purposes of this Section 1406(d), the term "tender
         offer" shall mean and include both tender offers and exchange offers,
         all references to "purchases" of shares in tender offers (and all
         similar references) shall mean and include both the purchase of shares
         in tender offers and the acquisition of shares pursuant to exchange
         offers, and all references to "tendered shares" (and all similar
         references) shall mean and include shares tendered in both tender
         offers and exchange offers.

                  (e) For the purpose of any computation under Sections 1406(b),
         1406(c) and 1406(d), the current market price per share of Common Stock
         on any date shall be deemed to be the average of the daily closing
         prices for the 30 consecutive Trading Days commencing 45 Trading Days
         before (i) the Determination Date or the Expiration Date, as the case
         may be, with respect to distributions or tender offers under Section
         1406(d) or (ii) the record date with respect to distributions,
         issuances or other events requiring such computation under Section
         1406(b) or Section 1406(c). The closing price for each day shall be the
         last reported sales price (regular way) or, in case no such reported
         sale takes place on such date, the average of the reported closing bid
         and asked prices in either case on the New York Stock Exchange (the
         "NYSE") or, if the Common Stock is not listed or admitted to trading on
         the NYSE, on the principal national securities exchange on which the
         Common Stock is listed or admitted to trading or, if not listed or
         admitted to trading on any national securities exchange, the last

                                      -29-
<PAGE>   32

         reported sales price of the Common Stock as quoted on Nasdaq (the term
         "Nasdaq" shall include, without limitation, the Nasdaq National Market)
         or, if no reported sales takes place, the average of the closing bid
         and asked prices as quoted on Nasdaq or any comparable system or, if
         the Common Stock is not quoted on Nasdaq or any comparable system, the
         closing sales price or, in case no reported sale takes place, the
         average of the closing bid and asked prices, as furnished by any two
         members of the National Association of Securities Dealers, Inc.
         selected from time to time by the Company for that purpose. If no such
         prices are available, the current market price per share shall be the
         fair value of a share of Common Stock as determined by the Board of
         Directors (which shall be evidenced by an Officer's Certificate
         delivered to the Trustee).

                  (f) In any case in which this Section 1406 shall require that
         an adjustment be made following a record date or a Determination Date
         or Expiration Date, as the case may be, established for purposes of
         this Section 1406, the Company may elect to defer (but only until five
         Business Days following the filing by the Company with the Trustee of
         the certificate described in Section 1409) issuing to the Holder of any
         2021 Debenture converted after such record date or Determination Date
         or Expiration Date the shares of Common Stock and other capital stock
         of the Company issuable upon such conversion over and above the shares
         of Common Stock and other capital stock of the Company issuable upon
         such conversion only on the basis of the Conversion Rate prior to
         adjustment; and, in lieu of the shares the issuance of which is so
         deferred, the Company shall issue or cause its transfer agents to issue
         due bills or other appropriate evidence prepared by the Company of the
         right to receive such shares. If any distribution in respect of which
         an adjustment to the Conversion Rate is required to be made as of the
         record date or Determination Date or Expiration Date therefor is not
         thereafter made or paid by the Company for any reason, the Conversion
         Rate shall be readjusted to the Conversion Rate that would then be in
         effect if such record date had not been fixed or such effective date or
         Determination Date or Expiration Date had not occurred.

         SECTION 1407 No Adjustment.

         No adjustment in the Conversion Rate shall be required unless the
         adjustment would require an increase or decrease of at least 1% in the
         Conversion Rate as last adjusted; provided, however, that any
         adjustments which by reason of this Section 1407 are not required to be
         made shall be carried forward and taken into account in any subsequent
         adjustment. All calculations under this Article FOURTEEN shall be made
         to the nearest cent or to the nearest 1/1000th of a share, as the case
         may be.

         No adjustment need be made for issuances of Common Stock pursuant to
         (a) any Company plan for reinvestment of dividends or interest or (b)
         any Company employee or director benefit or compensation plan, or for a
         change in the par value or a change to no par value of the Common
         Stock.

                                      -30-
<PAGE>   33

         To the extent that the 2021 Debentures become convertible into the
         right to receive cash, no adjustment need be made thereafter as to the
         cash. Interest will not accrue on the cash.

         SECTION 1408 Adjustment for Tax Purposes.

         The Company shall be entitled to make such adjustments in the
         Conversion Rate, in addition to those required by Section 1406, as it
         in its discretion shall determine to be advisable in order that any
         stock dividends, subdivisions of shares, distributions of rights to
         purchase stock or securities or distributions of securities convertible
         into or exchangeable for stock hereafter made by the Company to its
         stockholders shall not be taxable.

         SECTION 1409 Notice of Adjustment.

         Whenever the Conversion Rate is adjusted, the Company shall promptly
         mail to Holders a notice of the adjustment and file with the Trustee an
         Officer's Certificate specifying the adjusted Conversion Rate, the
         effective date of such adjustment and briefly stating the facts
         requiring the adjustment and the manner of computing it.

         SECTION 1410 Notice of Certain Transactions.

                  If:

               (a) the Company takes any action that would require an adjustment
         in the Conversion Rate,

               (b) the Company takes any action that requires a supplemental
         indenture pursuant to Section 1411, or

               (c) there is a dissolution or liquidation of the Company,

         the Company shall mail to Holders and file with the Trustee a notice
         stating the proposed record or effective date, as the case may be. The
         Company shall mail (or shall send by facsimile transmission promptly
         confirmed in writing mailed to the Trustee) the notice not less than 15
         days before such date. Failure to so give such notice or any defect
         therein shall not affect the validity of any transaction referred to in
         clause (a), (b) or (c) of this Section 1410.

         SECTION 1411 Effect of Reclassification, Consolidation, Merger or Sale
                      on Conversion Privilege.

         If any of the following shall occur, namely:

                  (a) any reclassification or change of shares of Common Stock
         issuable upon conversion of the 2021 Debentures (other than a change in
         par value, or

                                      -31-
<PAGE>   34

         from par value to no par value, or from no par value to par value, or
         as a result of a subdivision or combination);

                  (b) any consolidation or merger in which the Company is a
         party consolidating with another entity or merging with or into another
         entity other than a merger in which the Company is the continuing
         corporation and which does not result in any reclassification of, or
         change (other than a change in par value, or from par value to no par
         value, or from no par value to par value, or as a result of a
         subdivision or combination) in, outstanding shares of Common Stock; or

                  (c) any sale or conveyance of the properties and assets of the
         Company as, or substantially as, an entirety to any Person,

         then the Company, or such successor, purchasing or transferee
         corporation, as the case may be, shall, as a condition precedent to
         such reclassification, change, consolidation, merger, sale or
         conveyance, execute and deliver to the Trustee a supplemental indenture
         providing that the Holder of each 2021 Debenture then outstanding shall
         have the right to convert such 2021 Debenture into the kind and amount
         of shares of stock and other securities and property (including cash)
         receivable upon such reclassification, change, consolidation, merger,
         sale or conveyance by a holder of the number of shares of Common Stock
         deliverable upon conversion of such 2021 Debenture immediately prior to
         such reclassification, change, consolidation, merger, sale or
         conveyance; provided, however, that if the kind or amount of shares of
         stock and other securities and property (including cash) receivable
         upon such reclassification, change, consolidation, merger, sale or
         conveyance is not the same for each share of Common Stock of the
         Company held immediately prior to such reclassification, change,
         consolidation, merger, sale or conveyance in respect of which the
         holder(s) thereof shall not have exercised their rights of election in
         respect of consideration receivable for each share ("non-electing
         share"), then for the purpose of this Section 1411 the kind and amount
         of securities, cash and other property receivable upon such
         reclassification, change, consolidation, merger, sale or conveyance by
         each non-electing share shall be deemed to be the kind and amount so
         receivable per share by a plurality of the non-electing shares. Such
         supplemental indenture shall provide for adjustments of the Conversion
         Rate which shall be as nearly equivalent as may be practicable to the
         adjustments of the Conversion Rate provided for in this Article
         FOURTEEN. If, in the case of any such consolidation, merger, sale or
         conveyance, the stock or other securities and property (including cash)
         receivable thereupon by a holder of Common Stock include shares of
         stock or other securities and property of a Person other than the
         successor, purchasing or transferee corporation, as the case may be, in
         such consolidation, merger, sale or conveyance, then such supplemental
         indenture shall also be executed by such other Person and shall contain
         such additional provisions to protect the interests of the Holders of
         the 2021 Debentures as the Board of Directors shall reasonably consider
         necessary by reason of the foregoing. The provisions of this Section
         1411 shall similarly apply to successive reclassifications, changes,
         consolidations, mergers, sales or conveyances.

                                      -32-
<PAGE>   35

         If the Company shall (a) execute a supplemental indenture pursuant to
         this Section 1411, the Company shall promptly file with the Trustee (1)
         an Officer's Certificate briefly stating the reasons therefor, the kind
         or amount of shares of stock or other securities or property (including
         cash) receivable by Holders of the 2021 Debentures upon the conversion
         of their 2021 Debentures after any such reclassification, change,
         consolidation, merger, sale or conveyance, any adjustment to be made
         with respect thereto and that all conditions precedent have been
         complied with and (2) an Opinion of Counsel that all conditions
         precedent have been complied with, and (b) shall promptly mail notice
         thereof to all Holders.

         SECTION 1412 Trustee's Disclaimer.

         The Trustee shall have no duty to determine when an adjustment under
         this Article FOURTEEN should be made, how it should be made or what
         such adjustment should be, but may accept as conclusive evidence of
         that fact or the correctness of any such adjustment, and shall be
         protected in relying upon, an Officer's Certificate including the
         Officer's Certificate with respect thereto which the Company is
         obligated to file with the Trustee pursuant to Section 1409. The
         Trustee makes no representation as to the validity or value of any
         securities or assets issued upon conversion of 2021 Debentures, and the
         Trustee shall not be responsible for the Company's failure to comply
         with any provisions of this Article FOURTEEN.

         The Trustee shall not be under any responsibility to determine the
         correctness of any provisions contained in any supplemental indenture
         executed pursuant to Section 1411, but may accept as conclusive
         evidence of the correctness thereof, and shall be fully protected in
         relying upon, the Officer's Certificate with respect thereto which the
         Company is obligated to file with the Trustee pursuant to Section 1411.

         SECTION 1413 Voluntary Increase.

         The Company from time to time may increase the Conversion Rate, in
         addition to those which may be required pursuant to other provisions of
         this Article FOURTEEN, by any amount and for any period of time as the
         Company's Board of Directors determines to be in the best interests of
         the Company, provided that (a) the period of such increase is at least
         20 days or such longer period as may be required by law and (b) the
         increase is irrevocable during the period. Subsequent to any increase
         in the Conversion Rate made pursuant to this Section 1413, the Company
         may lower the Conversion Rate to any Conversion Rate that is not lower
         than the Conversion Rate that would have been applicable had the
         increase pursuant to this Section 1413 not been made. A determination
         by the Company's Board of Directors to increase or decrease the
         Conversion Rate in accordance with this Section 1413 shall be
         conclusive. If the Company increases or decreases the Conversion Rate,
         the Company will give at least seven days' advance notice of same, such
         notice to be given in accordance with Section 1410.

                                      -33-
<PAGE>   36

                                 ARTICLE FIFTEEN

                REPURCHASE OF SECURITIES AT OPTION OF THE HOLDER

         SECTION 1501 General.

                  The Company may be required to repurchase 2021 Debentures in
         accordance with their terms and in accordance with this Article
         FIFTEEN.

                  2021 Debentures shall be purchased by the Company under the
         paragraph "Repurchase by the Company at the Option of the Holder" of
         the 2021 Debentures on February 28, 2006, February 28, 2011 and
         February 28, 2016 (each, a "Repurchase Date"), at the repurchase price
         specified therein (each, a "Repurchase Price"), at the option of the
         Holder thereof, upon:

                  (1) delivery to the Paying Agent by the Holder of a written
         notice of purchase (a "Repurchase Notice") at any time during the
         period that commences on the opening of business on the date that is 20
         Business Days prior to a Repurchase Date and ends at the close of
         business on the Business Day next preceding such Repurchase Date
         stating:

                           (A) the certificate number of the 2021 Debenture
                  which the Holder will deliver to be repurchased or, if any of
                  the 2021 Debentures is in the form of a Global Security, then
                  a beneficial owner of a 2021 Debenture shall comply with the
                  procedures of the Depositary applicable to the repurchase of a
                  Global Security;

                           (B) the portion of the Principal Amount of the 2021
                  Debenture which the Holder will deliver to be repurchased,
                  which portion must be $1,000 or an integral multiple thereof;

                           (C) that such 2021 Debenture shall be purchased as of
                  the Repurchase Date pursuant to the terms and conditions
                  specified under the paragraph "Repurchase by the Company at
                  the Option of the Holder" in the 2021 Debentures and in this
                  Indenture;

                           (D) if the Company elects, pursuant to Section 1502
                  hereof, to pay the Repurchase Price to be paid as of such
                  Repurchase Date, in whole or in part, in Common Stock but such
                  portion of the Repurchase Price shall ultimately be payable to
                  such Holder entirely in cash because any of the conditions to
                  payment of the Repurchase Price in Common Stock is not
                  satisfied prior to the close of business on such Repurchase
                  Date, as set forth in Section 1502 or 1504 hereof, whether
                  such Holder elects (i) to withdraw such Repurchase Notice as
                  to some or all of the 2021 Debentures to which such Repurchase
                  Notice relates (stating the Principal Amount and certificate
                  numbers of the 2021 Debentures

                                      -34-
<PAGE>   37

                   as to which such withdrawal shall relate or if certificated
                   2021 Debentures have not been issued, a beneficial owner of
                   a 2021 Debenture shall comply with the procedures of the
                   Depositary applicable to the withdrawal of a Repurchase
                   Note), or (ii) to receive cash in respect of the entire
                   Repurchase Price for all 2021 Debentures (or portions
                   thereof) to which such Repurchase Price relates; and

                  (2) delivery of such 2021 Debenture(s) to the Paying Agent
         prior to, on or after the Repurchase Date (together with all necessary
         endorsements) at the offices of the Paying Agent, such delivery being a
         condition to receipt by the Holder of the Repurchase Price therefor;
         provided, however, that such Repurchase Price shall be so paid pursuant
         to this Article FIFTEEN only if the 2021 Debenture so delivered to the
         Paying Agent shall conform in all respects to the description thereof
         in the related Repurchase Notice.

         If a Holder, in such Holder's Repurchase Notice and in any written
         notice of withdrawal delivered by such Holder pursuant to the terms of
         Section 1509 hereof, fails to indicate such Holder's choice with
         respect to the election set forth in clause (D) of Section 1501(1),
         such Holder shall be deemed to have elected to receive cash in respect
         of the Repurchase Price for all 2021 Debentures subject to the
         Repurchase Notice in the circumstances set forth in such clause (D).

         The Company shall purchase from the Holder thereof, pursuant to this
         Article FIFTEEN, a portion of a 2021 Debenture if the Principal Amount
         of such portion is $1,000 or an integral multiple of $1,000. Provisions
         of this Indenture that apply to the purchase of all of a 2021 Debenture
         also apply to the purchase of such portion of such 2021 Debenture.

         Any purchase by the Company contemplated pursuant to the provisions of
         this Article FIFTEEN, shall be consummated by the delivery of the
         consideration to be received by the Holder promptly following the later
         of the Repurchase Date and the time of delivery of the 2021 Debenture.

         Notwithstanding anything herein to the contrary, any Holder delivering
         to the Paying Agent the Repurchase Notice contemplated by this Section
         1501 shall have the right to withdraw such Repurchase Notice at any
         time prior to the close of business on the Business Day next preceding
         the Repurchase Date by delivery of a written notice of withdrawal to
         the Paying Agent in accordance with Section 1509.

         The Paying Agent shall promptly notify the Company of the receipt by it
         of any Repurchase Notice or written notice of withdrawal thereof.

                                      -35-
<PAGE>   38

         SECTION 1502 The Company's Right to Elect Manner of Payment of
                      Repurchase Price.

                  The Repurchase Price of 2021 Debentures in respect of which a
         Repurchase Notice pursuant to Section 1501 has been given will be paid
         by the Company, at the election of the Company in its sole discretion,
         with cash or Common Stock or in any combination of cash and Common
         Stock, subject to the conditions set forth in this Section 1502 and in
         Section 1504 hereof. The Company shall designate, in the Company Notice
         delivered pursuant to Section 1505 hereof, whether the Company will
         purchase the 2021 Debentures for cash or Common Stock, or, if a
         combination thereof, the percentages of the Repurchase Price of 2021
         Debentures in respect of which it will pay in cash and Common Stock;
         provided, however, that the Company will pay cash for fractional
         interests in Common Stock. For purposes of determining the existence of
         potential fractional interests, all 2021 Debentures subject to purchase
         by the Company held by a Holder shall be considered together (no matter
         how many separate certificates are to be presented). Each Holder whose
         2021 Debentures are purchased pursuant to this Article FIFTEEN shall
         receive the same percentage of cash or Common Stock in payment of the
         Repurchase Price for such 2021 Debentures, except (i) as provided in
         Section 1504 with regard to the payment of cash in lieu of fractional
         Common Stock and (ii) if the Company is unable to purchase the 2021
         Debentures of a Holder or Holders for Common Stock because any
         necessary qualifications or registrations of the Common Stock under
         applicable state securities laws cannot be obtained, the Company may
         purchase the 2021 Debentures of such Holder or Holders for cash. The
         Company may not change its election with respect to the consideration
         (or components or percentages of components thereof) to be paid once
         the Company has given its Company Notice to Holders except pursuant to
         this Section 1502 or pursuant to Section 1504 hereof in the event of a
         failure to satisfy, prior to the close of business on the Repurchase
         Date, any condition to the payment of the Repurchase Price, in whole or
         in part, in Common Stock.

         Not less than five Business Days before the Company Notice Date, the
         Company shall deliver an Officer's Certificate to the Trustee
         specifying:

                  (i) the manner of payment selected by the Company;

                  (ii) the information required by Section 1505 hereof;

                  (iii) if the Company elects to pay the Repurchase Price, or a
         specified percentage thereof, in Common Stock, that the conditions to
         such manner of payment set forth in Section 1504 hereof have been or
         will be complied with; and

                  (iv) whether the Company desires the Trustee to give the
         Company Notice required by Section 1505 hereof.

                                      -36-
<PAGE>   39

         SECTION 1503 Purchase with Cash.

                  On each Repurchase Date, at the option of the Company, the
         Repurchase Price of 2021 Debentures in respect of which a Repurchase
         Notice pursuant to Section 1501 hereof has been given, or a specified
         percentage thereof, may be paid by the Company with cash equal to the
         aggregate Repurchase Price of such 2021 Debentures. If the Company
         elects to purchase 2021 Debentures with cash, the Company Notice, as
         provided in Section 1505 hereof, shall be sent to Holders (and to
         beneficial owners as required by applicable law) not less than 20
         Business Days prior to such Repurchase Date (the "Company Notice
         Date").

         SECTION 1504 Payment by Issuance of Common Stock.

                  On each Repurchase Date, at the option of the Company, the
         Repurchase Price of 2021 Debentures in respect of which a Repurchase
         Notice pursuant to Section 1501 hereof has been given, or a specified
         percentage thereof, may be paid by the Company by the issuance to the
         Holder(s) of such 2021 Debenture(s) of a number of shares of Common
         Stock equal to the quotient obtained by dividing (i) the amount of cash
         to which the Holder(s) would have been entitled had the Company elected
         to pay all or such specified percentage, as the case may be, of the
         Repurchase Price of such 2021 Debentures in cash by (ii) the Market
         Price of a share of Common Stock, subject to the next succeeding
         paragraph.

                  The Company will not issue any fractional shares of Common
         Stock in payment of the Repurchase Price. Instead the Company will pay
         cash for the current market value of the fractional share. The current
         market value of a fraction of a share of Common Stock shall be
         determined by multiplying the Market Price by such fraction and
         rounding the product to the nearest whole cent with one-half cent being
         rounded upwards. If a Holder elects to have more than one 2021
         Debenture repurchased, the number of shares of Common Stock shall be
         based on the aggregate amount of 2021 Debentures to be repurchased.

                  If the Company elects to purchase 2021 Debentures pursuant to
         this Article FIFTEEN by the issuance of Common Stock, the Company
         Notice, as provided in Section 1505, shall be sent to the Holders (and
         to beneficial owners as required by applicable law) not later than the
         Company Notice Date.

                  The Company's right to exercise its election to purchase the
         2021 Debentures pursuant to this Article FIFTEEN by issuing shares of
         Common Stock shall be conditioned upon:

                  (i) the Company's not having given its Company Notice of an
         election to pay entirely in cash and its giving of timely Company
         Notice of election to purchase all or a specified percentage of the
         2021 Debentures with Common Stock as provided herein;

                                      -37-
<PAGE>   40

                  (ii) the registration of the Common Stock to be issued in
         respect of the payment of the Repurchase Price under the Securities Act
         or the Exchange Act, in each case, if required for the initial issuance
         thereof;

                  (iii) any necessary qualification or registration under
         applicable state securities laws or the availability of an exemption
         from such qualification and registration; and

                  (iv) the receipt by the Trustee of an Officer's Certificate
         and an Opinion of Counsel each stating that (A) the terms of the
         issuance of the Common Stock are in conformity with this Indenture and
         (B) the shares of Common Stock to be issued by the Company in payment
         of the Repurchase Price in respect of 2021 Debentures have been duly
         authorized and, when issued and delivered pursuant to the terms of this
         Indenture in payment of the Repurchase Price in respect of the 2021
         Debentures, will be validly issued, fully paid and nonassessable and,
         to such counsel's knowledge, free from preemptive rights, and, in the
         case of such Officer's Certificate, stating that conditions (i), (ii)
         and (iii) above and the condition set forth in the second sentence of
         the immediately following paragraph have been satisfied and, in the
         case of such Opinion of Counsel, stating that conditions (ii) and (iii)
         above have been satisfied.

                  Such Officer's Certificate shall also set forth the number of
         shares of Common Stock to be issued for each $1,000 Principal Amount at
         Maturity of 2021 Debentures and the Sale Price of a share of Common
         Stock on each Trading Day during the period commencing on the first
         Trading Day of the period during which the Market Price is calculated
         and ending three Business Days prior to the applicable Repurchase Date
         (if the third Business Day prior to the applicable Repurchase Date is a
         Trading Day, or if not, then on the last Trading Day prior to such
         third Business Day). The Company may pay the Repurchase Price (or any
         portion thereof) in Common Stock only if the information necessary to
         calculate the Market Price is published in The Wall Street Journal or
         another daily newspaper of national circulation. If the conditions set
         forth in this paragraph and the immediately preceding paragraph are not
         satisfied with respect to a Holder or Holders prior to the close of
         business on the Repurchase Date and the Company has elected to
         repurchase the 2021 Debentures pursuant to this Article FIFTEEN through
         the issuance of Common Stock, the Company shall pay, without further
         notice, the entire Repurchase Price of the 2021 Debentures of such
         Holder or Holders in cash.

                  The term "Market Price" as used in this Section 1504 means the
         average of the Sale Prices of the Common Stock for the five Trading Day
         period ending on (if the third Business Day prior to the applicable
         Repurchase Date is a Trading Day, or if not, then on the last Trading
         Day prior to), the third Business Day prior to the applicable
         Repurchase Date appropriately adjusted to take into account the
         occurrence, during the period commencing on the first of such Trading
         Days during such five Trading Day period and ending on such Repurchase
         Date, of any

                                      -38-
<PAGE>   41

         event described in Section 1406; subject, however, to the conditions
         set forth in Sections 1406(f) and 1407.

                  The term "Sale Price" as used in this Section 1504 of the
         Common Stock on any date as used in this Section means the closing per
         share sale price (or, if no closing sale price is reported, the average
         of the bid and ask prices or, if more than one in either case, the
         average of the average bid and average ask prices) on such date as
         reported in the composite transactions for the principal United States
         securities exchange on which the Common Stock is listed for trading or,
         if the Common Stock is not listed on a United States national or
         regional securities exchange, as reported by the National Association
         of Securities Dealers Automated Quotation System or its successors.

         SECTION 1505 Notice of Election.

                  The Company's notice of election to repurchase with cash or
         Common Stock or any combination thereof shall be sent to the Holders in
         the manner provided in Section 106 of the Indenture at the time
         specified in Section 1503 or 1504 hereof, as applicable (the "Company
         Notice"). Such Company Notice shall state the manner of payment elected
         and shall contain the following information:

                  If the Company has elected to pay the Repurchase Price (or a
         specified percentage thereof) with Common Stock, the Company Notice
         shall:

                  (1) state that each Holder will receive Common Stock with a
         Market Price equal to such specified percentage of the Repurchase Price
         of the 2021 Debentures held by such Holder (except any cash amount to
         be paid in lieu of fractional shares);

                  (2) set forth the method of calculating the Market Price of
         the Common Stock; and

                  (3) state that because the Market Price of Common Stock will
         be determined prior to the Repurchase Date, Holders will bear the
         market risk with respect to the value of the Common Stock to be
         received from the date such Market Price is determined to the
         Repurchase Date.

                  In any case, each Company Notice shall include a form of
         Repurchase Notice to be completed by a Holder and shall state:

                           (A) the Repurchase Price and the Conversion Rate;

                           (B) the name and address of the Paying Agent and the
                  Conversion Agent;

                           (C) that 2021 Debentures as to which a Repurchase
                  Notice has been given may be converted pursuant to Article

                                      -39-
<PAGE>   42

                  FOURTEEN hereof only if the applicable Repurchase Notice has
                  been withdrawn in accordance with the terms of this Indenture;

                           (D) that 2021 Debentures must be surrendered to the
                  Paying Agent to collect payment;

                           (E) that the Repurchase Price for any 2021 Debenture
                  as to which a Repurchase Notice has been given and not
                  withdrawn will be paid promptly following the later of the
                  Repurchase Date and the time of surrender of such 2021
                  Debenture as described in clause (D) of this paragraph;

                           (F) the procedures the Holder must follow to exercise
                  repurchase rights under this Article FIFTEEN and a brief
                  description of those rights;

                           (G) briefly, the conversion rights of the 2021
                  Debentures; and

                           (H) the procedures for withdrawing a Repurchase
                  Notice (including, without limitation, for a conditional
                  withdrawal pursuant to the terms of Section 1501 or Section
                  1509).

                  At the Company's request in accordance with Section 1502, the
         Trustee shall give such Company Notice in the Company's name and at the
         Company's expense; provided, however, that, in all cases, the text of
         such Company Notice shall be prepared by the Company.

                  Upon determination of the actual number of shares of Common
         Stock to be issued for each $1,000 Principal Amount of 2021 Debentures,
         the Company will publish such determination at the Company's Web site
         on the World Wide Web or through such other public medium as the
         Company may use at that time.

         SECTION 1506 Covenants of the Company.

                  All Common Stock delivered upon purchase of the 2021
         Debentures shall be newly issued shares or treasury shares, shall be
         duly authorized, validly issued, fully paid and nonassessable and shall
         be free from preemptive rights and free of any lien or adverse claim.
         The Company shall use its reasonable efforts to list for trading or
         cause to have quoted any Common Stock to be issued to purchase 2021
         Debentures on the principal national securities exchange or
         over-the-counter or other domestic market on which the Common Stock is
         then listed for trading or quoted.

         SECTION 1507 Procedure upon Repurchase.

                  The Company shall deposit cash (in respect of a cash purchase
         under Section 1503 or for fractional shares of Common Stock, as
         applicable) or

                                      -40-
<PAGE>   43

         Common Stock, or a combination thereof, as applicable, at the time and
         in the manner as provided in Section 1510, sufficient to pay the
         aggregate Repurchase Price of all 2021 Debentures to be purchased on
         the applicable Repurchase Date pursuant to this Article FIFTEEN.

                  As soon as practicable after the Repurchase Date, the Company
         shall deliver to each Holder entitled to receive Common Stock through
         the Paying Agent, a certificate for the number of full shares of Common
         Stock issuable in payment of the Repurchase Price and cash in lieu of
         any fractional shares of Common Stock. The Person in whose name the
         certificate for Common Stock is registered shall be treated as a holder
         of record of Common Stock on the Business Day following the Repurchase
         Date. No payment or adjustment will be made for dividends on the Common
         Stock the record date for which occurred on or prior to the Repurchase
         Date.

         SECTION 1508 Taxes.

                  If a Holder of a 2021 Debenture is paid in Common Stock, the
         Company shall pay any documentary, stamp or similar issue or transfer
         tax due on such issue of Common Stock. However, the Holder shall pay
         any such tax which is due because the Holder requests the Common Stock
         to be issued in a name other than the Holder's name. The Paying Agent
         may refuse to deliver the certificates representing the shares of
         Common Stock being issued in a name other than the Holder's name until
         the Paying Agent receives a sum sufficient to pay any tax which will be
         due because the shares of Common Stock are to be issued in a name other
         than the Holder's name.

         SECTION 1509 Effect of Repurchase Notice.

                  Upon receipt by the Paying Agent of the Repurchase Notice, the
         Holder of the 2021 Debenture in respect of which such Repurchase Notice
         was given shall (unless such Repurchase Notice is withdrawn as
         specified in the following two paragraphs) thereafter be entitled to
         receive solely the Repurchase Price with respect to such 2021
         Debenture. Such Repurchase Price shall be paid to such Holder, subject
         to receipt of funds and/or Common Stock by the Paying Agent, promptly
         following the later of (x) the Repurchase Date with respect to such
         2021 Debenture (provided the conditions in Section 1501 have been
         satisfied) and (y) the time of delivery of such 2021 Debenture to the
         Paying Agent by the Holder thereof in the manner required by Section
         1501. 2021 Debentures in respect of which a Repurchase Notice has been
         given by the Holder thereof may not be converted pursuant to Article
         FOURTEEN hereof on or after the date of the delivery of such Repurchase
         Notice unless such Repurchase Notice has first been validly withdrawn
         as specified in the following two paragraphs.

                  A Repurchase Notice may be withdrawn by means of a written
         notice of withdrawal delivered to the office of the Paying Agent in
         accordance with the Repurchase Notice at any time prior to the close of
         business on the Business Day next preceding the applicable Repurchase
         Date specifying:

                                      -41-
<PAGE>   44

                  (1) the certificate number of the 2021 Debenture in respect of
         which such notice of withdrawal is being submitted or, if any of the
         2021 Debentures is in the form of a Global Security, then a beneficial
         owner of a 2021 Debenture shall comply with the procedures of the
         Depositary applicable to the withdrawal of a Repurchase Notice;

                  (2) the Principal Amount of the 2021 Debenture with respect
         to which such notice of withdrawal is being submitted; and

                  (3) the Principal Amount, if any, of such 2021 Debenture which
         remains subject to the original Repurchase Notice and which has been or
         will be delivered for purchase by the Company.

                  A written notice of withdrawal of a Repurchase Notice may be
         in the form set forth in the preceding paragraph or may be in the form
         of (i) a conditional withdrawal contained in a Repurchase Notice
         pursuant to the terms of Section 1501(1)(D) or (ii) a conditional
         withdrawal containing the information set forth in Section 1501(1)(D)
         and the preceding paragraph and contained in a written notice of
         withdrawal delivered to the Paying Agent as set forth in the preceding
         paragraph.

                  There shall be no purchase of any 2021 Debentures pursuant to
         this Article FIFTEEN (other than through the issuance of Common Stock
         in payment of the Repurchase Price, including cash in lieu of
         fractional shares) if there has occurred (prior to, on or after, as the
         case may be, the giving, by the Holders of such 2021 Debentures, of the
         required Repurchase Notice) and is continuing an Event of Default
         (other than a default in the payment of the Repurchase Price with
         respect to such 2021 Debentures). The Paying Agent will promptly return
         to the respective Holders thereof any 2021 Debentures (x) with respect
         to which a Repurchase Notice has been withdrawn in compliance with this
         Indenture, or (y) held by it during the continuance of an Event of
         Default (other than a default in the payment of the Repurchase Price
         with respect to such 2021 Debentures) in which case, upon such return,
         the Repurchase Notice with respect thereto shall be deemed to have been
         withdrawn.

         SECTION 1510 Deposit of Repurchase Price.

                  Prior to 11:00 a.m. (New York City time) on the Business Day
         following the Repurchase Date, the Company shall deposit with the
         Trustee or with the Paying Agent an amount of money (in immediately
         available funds if deposited on such Business Day) and/or Common Stock,
         if permitted hereunder, sufficient to pay the aggregate Repurchase
         Price of all of the 2021 Debentures or portions thereof which are to be
         purchased as of the Repurchase Date.

                                      -42-
<PAGE>   45

         SECTION 1511 Securities Repurchased in Part.

                  Any 2021 Debenture which is to be purchased only in part shall
         be surrendered at the office of the Paying Agent (with, if the Company
         or the Trustee so requires, due endorsement by, or a written instrument
         of transfer in form satisfactory to the Company or the Trustee duly
         executed by, the Holder thereof or such Holder's attorney duly
         authorized in writing) and the Company shall execute and the Trustee
         shall authenticate and deliver to the Holder of such 2021 Debenture,
         without service charge, a new 2021 Debenture or 2021 Debentures, of any
         authorized denomination as requested by such Holder in aggregate
         Principal Amount equal to, and in exchange for, the portion of the
         Principal Amount of the 2021 Debenture so surrendered which is not
         purchased.

         SECTION 1512 Comply with Securities Laws Upon Purchase of Securities.

                  In connection with any offer to purchase or purchase of 2021
         Debentures under this Article FIFTEEN (provided that such offer or
         purchase constitutes an "issuer tender offer" for purposes of Rule
         13e-4 (which term, as used herein, includes any successor provision
         thereto) under the Exchange Act at the time of such offer or purchase),
         the Company shall (i) comply with Rule 13e-4 under the Exchange Act,
         (ii) file the related Schedule TO (or any successor schedule, form or
         report) under the Exchange Act and (iii) otherwise comply with all
         Federal and state securities laws so as to permit the rights and
         obligations under this Article FIFTEEN to be exercised in the time and
         in the manner specified in this Article FIFTEEN.

         SECTION 1513 Repayment to the Company.

                  The Trustee and the Paying Agent shall return to the Company
         any cash or Common Stock that remain unclaimed for two years, subject
         to applicable unclaimed property law, together with interest or
         dividends, if any, thereon held by them for the payment of the
         Repurchase Price; provided, however, that to the extent that the
         aggregate amount of cash or Common Stock deposited by the Company
         pursuant to Section 1510 exceeds the aggregate Repurchase Price of the
         2021 Debentures or portions thereof which the Company is obligated to
         purchase as of the Repurchase Date, then promptly after the Business
         Day following the Repurchase Date the Trustee shall return any such
         excess to the Company together with interest or dividends, if any,
         thereon. After that, Holders entitled to money or Common Stock must
         look to the Company for payment as general creditors, unless an
         applicable abandoned property law designates another Person, and all
         liability of the Trustee and the Paying Agent with respect to such
         money or Common Stock shall thereupon cease.

         SECTION 1514 Conversion Arrangement on Repurchase.

                  Any 2021 Debentures required to be repurchased under this
         Article FIFTEEN, unless surrendered for conversion before the close of
         business on the

                                      -43-
<PAGE>   46

         Repurchase Date, may be deemed to be purchased from the Holders of
         such 2021 Debentures for an amount in cash equal to not less than the
         Repurchase Price, by one or more investment bankers or other
         purchasers who may agree with the Company to purchase such Securities
         from the Holders, to convert them into Common Stock of the Company and
         to make payment for such 2021 Debentures to the Trustee in trust for
         such Holders.

                                 ARTICLE SIXTEEN

                       PURCHASE OF SECURITIES AT OPTION OF
                        THE HOLDER UPON CHANGE IN CONTROL

         SECTION 1601 Right to Require Repurchase.

                  (a) If at any time that 2021 Debentures remain Outstanding
         there shall occur a Change in Control, 2021 Debentures shall be
         purchased by the Company at the option of the Holders thereof as of the
         date that is 35 Business Days after the occurrence of the Change in
         Control (the "Change in Control Purchase Date") at a purchase price
         equal to the Issue Price plus accrued Original Issue Discount through
         the Change in Control Purchase Date (or, if the option under Section
         1701 has been exercised, the Restated Principal Amount plus accrued and
         unpaid interest from the later of the Option Exercise Date and the date
         on which interest was last paid or duly provided for to the Change in
         Control Purchase Date) (the "Change in Control Purchase Price"),
         subject to satisfaction by or on behalf of any Holder of the
         requirements set forth in Section 1601(c).

                  As used in this Section 1601, the term "Change in Control"
         shall be deemed to have occurred at such time as (a) any Person, or any
         Persons acting together in a manner which would constitute a "group" (a
         "Group") for purposes of Section 13(d) of the Exchange Act, or any
         successor provision thereto, together with any Affiliates thereof
         become the Beneficial Owners, directly or indirectly, of capital stock
         of the Company, entitling such Person or Persons and its or their
         Affiliates to exercise more than 50% of the total voting power of all
         classes of the Company's capital stock entitled to vote generally in
         the election of the Company's directors or (b) the Company shall
         consolidate with or merge into any other Person (other than a
         Subsidiary), or any other Person (other than a Subsidiary) shall
         consolidate with or merge into the Company, or the Company shall sell,
         convey, transfer or lease its properties and assets substantially as an
         entirety to any Person (other than a Subsidiary), and, in the case of
         any such transaction the outstanding Common Stock is reclassified into,
         exchanged for or converted into the right to receive any other property
         or security, unless the stockholders of the Company immediately before
         such transaction beneficially own, directly or indirectly, immediately
         following such transaction, at least a majority of the combined voting
         power of the outstanding voting securities of the Person resulting from
         such transaction or the Person acquiring such properties and assets,
         entitled to vote generally in the election of such resulting or
         acquiring

                                      -44-
<PAGE>   47

         Person's directors, in substantially the same proportion as their
         ownership of the Common Stock immediately before such transaction,
         provided, however, that, with respect to both clauses (a) and (b) of
         this definition, a Change in Control shall not be deemed to have
         occurred if at least 50% of the consideration (excluding cash payments
         for fractional shares) in the transaction or transactions constituting
         the Change in Control consists of shares of voting common stock of
         such Person that are, or upon issuance will be, traded on a United
         States national securities exchange or approved for trading on an
         established automated over-the-counter trading market in the United
         States.

                  As used in this Section 1601, the term "Beneficial Owner"
         shall be determined in accordance with Rules 13d-3 and 13d-5
         promulgated by the Securities and Exchange Commission under the
         Exchange Act or any successor provision thereto, except that a Person
         shall be deemed to have "beneficial ownership" of all shares that such
         Person has the right to acquire, whether such right is exercisable
         immediately or only after the passage of time.

                  (b) Within 15 Business Days after the occurrence of a Change
         in Control, the Company shall mail a written notice of the Change in
         Control to the Trustee and to each Holder. The notice shall include the
         form of a Change in Control Purchase Notice to be completed by the
         Holder and shall state:

                           (1) the date of such Change in Control and, briefly,
                  the events causing such Change in Control;

                           (2) the date by which the Change in Control Purchase
                  Notice pursuant to this Section 1601 must be given;

                           (3) the Change in Control Purchase Date;

                           (4) the Change in Control Purchase Price;

                           (5) briefly, the conversion rights of the 2021
                  Debentures;

                           (6) the name and address of each Paying Agent and
                  Conversion Agent;

                           (7) the Conversion Rate and any adjustments thereto;

                           (8) that 2021 Debentures as to which a Change in
                  Control Purchase Notice has been given may be converted into
                  Common Stock pursuant to Article FOURTEEN only to the extent
                  that the Change in Control Purchase Notice has been withdrawn
                  in accordance with the terms of this Indenture;

                           (9) the procedures that the Holder must follow to
                  exercise rights under this Section 1601;

                                      -45-
<PAGE>   48

                           (10) the procedures for withdrawing a Change in
                  Control Purchase Notice, including a form of notice of
                  withdrawal; and

                           (11) that the Holder must satisfy the requirements
                  set forth in the 2021 Debentures in order to convert the
                  Securities.

                  If any of the 2021 Debentures is in the form of a Global
         Security, then the Company shall modify such notice to the extent
         necessary to accord with the procedures of the Depositary applicable to
         the repurchase of Global Securities.

                  (c) A Holder may exercise its rights specified in subsection
         (a) of this Section 1601 upon delivery of a written notice (which shall
         be in substantially the form included as an attachment to the 2021
         Debentures and which may be delivered by letter, overnight courier,
         hand delivery, facsimile transmission or in any other written form and,
         in the case of Global Securities, may be delivered electronically or by
         other means in accordance with the Depositary's customary procedures)
         of the exercise of such rights (a "Change in Control Purchase Notice")
         to any Paying Agent at any time prior to the close of business on the
         Business Day next preceding the Change in Control Purchase Date.

                  The delivery of such 2021 Debenture to any Paying Agent
         (together with all necessary endorsements) at the office of such Paying
         Agent shall be a condition to the receipt by the Holder of the Change
         in Control Purchase Price therefor.

                  The Company shall purchase from the Holder thereof, pursuant
         to this Section 1601, a portion of a 2021 Debenture if the Principal
         Amount of such portion is $1,000 or an integral multiple of $1,000.
         Provisions of this Indenture that apply to the purchase of all of a
         2021 Debenture pursuant to Sections 1601 through 1606 also apply to the
         purchase of such portion of such 2021 Debenture.

                  Notwithstanding anything herein to the contrary, any Holder
         delivering to a Paying Agent the Change in Control Purchase Notice
         contemplated by this Section 1601(c) shall have the right to withdraw
         such Change in Control Purchase Notice in whole or as to a portion
         thereof that is a Principal Amount of $1,000 or an integral multiple
         thereof at any time prior to the close of business on the Business Day
         next preceding the Change in Control Purchase Date by delivery of a
         written notice of withdrawal to the Paying Agent in accordance with
         Section 1602.

                  A Paying Agent shall promptly notify the Company of the
         receipt by it of any Change in Control Purchase Notice or written
         withdrawal thereof.

                  Anything herein to the contrary notwithstanding, in the case
         of Global Securities, any Change in Control Purchase Notice may be
         delivered or withdrawn and such 2021 Debentures may be surrendered or
         delivered for purchase in accordance with the applicable procedures of
         the Depositary as in effect from time to time.

                                      -46-
<PAGE>   49

         SECTION 1602 Effect of Change in Control Purchase Notice.

                  Upon receipt by any Paying Agent of the Change in Control
         Purchase Notice specified in Section 1601(c), the Holder of the 2021
         Debenture in respect of which such Change in Control Purchase Notice
         was given shall (unless such Change in Control Purchase Notice is
         withdrawn as specified below) thereafter be entitled to receive the
         Change in Control Purchase Price with respect to such 2021 Debenture.
         Such Change in Control Purchase Price shall be paid to such Holder
         promptly following the later of (a) the Change in Control Purchase Date
         with respect to such 2021 Debenture (provided the conditions in Section
         1601(c) hereof have been satisfied) and (b) the time of delivery of
         such 2021 Debenture to a Paying Agent by the Holder thereof in the
         manner required by Section 1601(c) hereof. 2021 Debentures in respect
         of which a Change in Control Purchase Notice has been given by the
         Holder thereof may not be converted into Common Stock on or after the
         date of the delivery of such Change in Control Purchase Notice unless
         such Change in Control Purchase Notice has first been validly
         withdrawn.

                  A Change in Control Purchase Notice may be withdrawn by means
         of a written notice (which may be delivered by letter, overnight
         courier, hand delivery, facsimile transmission or in any other written
         form and, in the case of Global Securities, may be delivered
         electronically or by other means in accordance with the Depositary's
         customary procedures) of withdrawal delivered by the Holder to a Paying
         Agent at any time prior to the close of business on the Business Day
         immediately preceding the Change in Control Purchase Date, specifying
         the Principal Amount of the Security or portion thereof (which must be
         a Principal Amount of $1,000 or an integral multiple of $1,000 in
         excess thereof) with respect to which such notice of withdrawal is
         being submitted.

         SECTION 1603 Deposit of Change in Control Purchase Price.

                  On or before 11:00 a.m. New York City time on the Change in
         Control Purchase Date, the Company shall deposit with the Trustee or
         with a Paying Agent (other than the Company or an Affiliate of the
         Company) an amount of money (in immediately available funds if
         deposited on such Business Day) sufficient to pay the aggregate Change
         in Control Purchase Price of all the 2021 Debentures or portions
         thereof that are to be purchased as of such Change in Control Purchase
         Date. The manner in which the deposit required by this Section 1603 is
         made by the Company shall be at the option of the Company, provided,
         however, that such deposit shall be made in a manner such that the
         Trustee or a Paying Agent shall have immediately available funds on the
         Change in Control Purchase Date.

                  If a Paying Agent holds, in accordance with the terms hereof,
         money sufficient to pay the Change in Control Purchase Price of any
         2021 Debenture for which a Change in Control Purchase Notice has been
         tendered and not withdrawn in accordance with this Indenture then, on
         the Change in Control Purchase Date, such 2021 Debenture will cease to
         be outstanding and the rights of the Holder in

                                      -47-
<PAGE>   50

         respect thereof shall terminate (other than the right to receive the
         Change in Control Purchase Price as aforesaid). The Company shall
         publicly announce the Principal Amount of 2021 Debentures purchased as
         a result of such Change in Control on or as promptly as practicable
         after the Change in Control Purchase Date.

         SECTION 1604 Securities Purchased In Part.

                  Any 2021 Debenture that is to be purchased only in part shall
         be surrendered at the office of a Paying Agent and promptly after the
         Change in Control Purchase Date the Company shall execute and the
         Trustee shall authenticate and deliver to the Holder of such 2021
         Debenture, without service charge, a new 2021 Debenture or 2021
         Debentures, of such authorized denomination or denominations as may be
         requested by such Holder, in aggregate Principal Amount equal to, and
         in exchange for, the portion of the Principal Amount of the 2021
         Debenture so surrendered that is not purchased.

         SECTION 1605 Compliance With Securities Laws Upon Purchase of
                      Securities.

                  In connection with any offer to purchase or purchase of 2021
         Debentures under Section 1601, the Company shall (a) comply with Rule
         13e-4 (or any successor to either such Rule), if applicable, under the
         Exchange Act, (b) file the related Schedule TO (or any successor or
         similar schedule, form or report) if required under the Exchange Act,
         and (c) otherwise comply with all federal and state securities laws in
         connection with such offer, all so as to permit the rights of the
         Holders and obligations of the Company under Sections 1601 through 1606
         hereof to be exercised in the time and in the manner specified therein.

         SECTION 1606 Repayment to the Company.

                  To the extent that the aggregate amount of cash deposited by
         the Company pursuant to Section 1603 hereof exceeds the aggregate
         Change in Control Purchase Price together with interest, if any,
         thereon of the 2021 Debentures or portions thereof that the Company is
         obligated to purchase, then promptly after the Change in Control
         Purchase Date the Trustee or a Paying Agent, as the case may be, shall
         return any such excess to the Company.

                                ARTICLE SEVENTEEN

                          SPECIAL TAX EVENT CONVERSION

         SECTION 1701 Optional Conversion to Interest-Bearing Securities Upon
                      Tax Event.

                  From and after (i) the date (the "Tax Event Date") of the
         occurrence of a Tax Event and (ii) the date the Company exercises such
         option (which exercise

                                      -48-
<PAGE>   51

         shall be evidenced by written notice delivered to the Trustee stating
         that a Tax Event has occurred and the Company has exercised such
         option or that, if a Tax Event shall occur and if the Company shall
         have given the Trustee notice thereof, the Company shall be deemed to
         have exercised such option), whichever is later (the "Option Exercise
         Date"), at the option of the Company with respect to its 2021
         Debentures only, interest in lieu of Original Issue Discount shall
         accrue at the rate of 4.00% per annum on a restated principal amount
         per $1,000 original Principal Amount (the "Restated Principal Amount")
         equal to the Issue Price plus Original Issue Discount accrued to the
         Option Exercise Date and shall be payable semi-annually on each
         Interest Payment Date (as defined in the 2021 Debentures) to holders
         of record at the close of business on each Regular Record Date (as
         defined in the 2021 Debentures) immediately preceding such Interest
         Payment Date. Interest will be computed on the basis of a 360-day year
         comprised of twelve 30-day months and will accrue from the most recent
         date on which interest has been paid or duly provided for or, if no
         interest has been paid, from the Option Exercise Date. Within 15 days
         after the occurrence of a Tax Event, the Company shall mail a written
         notice of such Tax Event by first-class mail to the Trustee and within
         15 days of its exercise of such option the Company shall mail a
         written notice of the Option Exercise Date by first-class mail to the
         Trustee and Holders of the 2021 Debentures. From and after the Option
         Exercise Date, (i) the Company shall be obligated to pay at Stated
         Maturity, in lieu of the Principal Amount of a Security, the Restated
         Principal Amount thereof and (ii) "Issue Price and accrued Original
         Issue Discount," "Issue Price plus Original Issue Discount" or similar
         words, as used herein, shall mean Restated Principal Amount plus
         accrued and unpaid interest with respect to any 2021 Debenture. 2021
         Debentures authenticated and delivered after the Option Exercise Date
         may, and shall if required by the Trustee, bear a notation in a form
         approved by the Trustee as to the conversion of the 2021 Debentures to
         interest-bearing 2021 Debentures.

                                  ARTICLE III

                            MISCELLANEOUS PROVISIONS

Section 301 Integral Part.

         This Fifth Supplemental Indenture constitutes an integral part of the
Indenture with respect to the 2021 Debentures only.

Section 302 General Definitions.

         For all purposes of this Fifth Supplemental Indenture:

         (a) capitalized terms used herein without definition shall have the
meanings specified in the Indenture; and

         (b) the terms "herein", "hereof", "hereunder" and other words of
similar import refer to this Fifth Supplemental Indenture.

                                      -49-
<PAGE>   52

Section 303 Adoption, Ratification and Confirmation.

         The Indenture, as supplemented and amended by this Fifth Supplemental
Indenture, is in all respects hereby adopted, ratified and confirmed, and, as
provided in the Original Indenture, this Fifth Supplemental Indenture shall be
deemed part of the Indenture in the manner and to the extent herein and therein
provided. The provisions of this Fifth Supplemental Indenture shall, subject to
the terms hereof, supersede the provisions of the Original Indenture to the
extent the Original Indenture is inconsistent herewith.

Section 304 Trust Indenture Act Controls.

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

Section 305 Governing Law.

         THIS FIFTH SUPPLEMENTAL INDENTURE AND THE 2021 DEBENTURES SHALL BE
GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK,
WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAWS TO THE
EXTENT THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

Section 306 Severability.

         In case any provision in this Fifth Supplemental Indenture or in the
2021 Debentures shall be invalid, illegal or unenforceable, the validity,
legality and enforceability of the remaining provisions shall, to the fullest
extent permitted by applicable law, not in any way be affected or impaired
thereby.

Section 307 Counterpart Originals.

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

Section 308 Successors.

         All agreements of the Company in this Fifth Supplemental Indenture and
the 2021 Debentures shall bind its successors. All agreements of the Trustee in
this Fifth Supplemental Indenture shall bind its successors.

Section 309 Table of Contents, Headings, etc..

         The table of contents, cross-reference table and headings of the
Articles and Sections of this Fifth Supplemental Indenture have been inserted
for convenience of reference only, are not to be considered a part hereof and
shall in no way modify or restrict any of the terms or provisions hereof.

                                      -50-
<PAGE>   53

Section 310 Benefit of Fifth Supplemental Indenture.

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

Section 311 Acceptance by Trustee.

         The Trustee accepts the amendments to the Indenture effected by this
Fifth Supplemental Indenture and agrees to execute the trusts created by the
Indenture as hereby amended, but only upon the terms and conditions set forth in
this Fifth Supplemental Indenture and the Indenture. Without limiting the
generality of the foregoing, the Trustee assumes no responsibility for the
correctness of the recitals contained herein, which shall be taken as the
statements of the Company, and except as provided in the Indenture the Trustee
shall not be responsible or accountable in any way whatsoever for or with
respect to the validity or execution or sufficiency of this Fifth Supplemental
Indenture and the Trustee makes no representation with respect thereto. The
Trustee shall not be accountable for the use or application by the Company of
the 2021 Debentures or of the proceeds thereof.

                                      -51-
<PAGE>   54

         IN WITNESS WHEREOF, said EL PASO CORPORATION has caused this Fifth
Supplemental Indenture to be duly executed in its corporate name by its Chairman
of the Board, or its President or one of its Vice Presidents, and said THE CHASE
MANHATTAN BANK has caused this Fifth Supplemental Indenture to be executed in
its corporate name by one of its Assistant Vice Presidents as of the day and
year first written above.

                                             EL PASO CORPORATION

                                             By: /s/ JOHN HOPPER
                                                 -------------------------------
                                                 Name: John Hopper
                                                      --------------------------
                                                 Title: Vice President
                                                       -------------------------

                                             THE CHASE MANHATTAN BANK

                                             By: /s/ R. LORENZEN
                                                 -------------------------------
                                                 Name: R. Lorenzen
                                                      --------------------------
                                                 Title: Assistant Vice President
                                                       -------------------------

                                      -52-
<PAGE>   55

                                                                         ANNEX A

                                 GLOBAL SECURITY
                           [FORM OF FACE OF SECURITY]

         FOR UNITED STATES FEDERAL INCOME TAX PURPOSES, THIS SECURITY BEARS
ORIGINAL ISSUE DISCOUNT. INFORMATION INCLUDING THE ISSUE PRICE, AMOUNT OF
ORIGINAL ISSUE DISCOUNT, THE ISSUE DATE AND THE YIELD TO MATURITY WILL BE MADE
AVAILABLE TO HOLDERS UPON REQUEST TO THE INVESTOR RELATIONS DEPARTMENT OF THE
COMPANY, AT (713) 420-2131.

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

         THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE
HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY OR A
NOMINEE THEREOF. THIS SECURITY MAY NOT BE TRANSFERRED TO, OR REGISTERED OR
EXCHANGED FOR SECURITIES REGISTERED IN THE NAME OF, ANY PERSON OTHER THAN THE
DEPOSITARY OR A NOMINEE THEREOF AND NO SUCH TRANSFER MAY BE REGISTERED, EXCEPT
IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE. EVERY SECURITY
AUTHENTICATED AND DELIVERED UPON REGISTRATION OF TRANSFER OF, OR IN EXCHANGE FOR
OR IN LIEU OF, THIS SECURITY SHALL BE A GLOBAL SECURITY SUBJECT TO THE
FOREGOING, EXCEPT IN SUCH LIMITED CIRCUMSTANCES.](1)

         [THIS DEBENTURE (OR ITS PREDECESSOR) WAS ORIGINALLY ISSUED IN A
TRANSACTION EXEMPT FROM REGISTRATION UNDER THE UNITED STATES SECURITIES ACT OF
1933 (THE "SECURITIES ACT"), AND THIS DEBENTURE AND THE COMMON STOCK ISSUABLE
UPON CONVERSION THEREOF MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED IN THE
ABSENCE OF SUCH REGISTRATION OR AN APPLICABLE EXEMPTION THEREFROM. EACH
PURCHASER OF THIS DEBENTURE IS HEREBY NOTIFIED THAT THE SELLER OF THIS DEBENTURE
MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE
SECURITIES ACT PROVIDED BY RULE 144A THEREUNDER.

---------

(1)  These paragraphs should be included only if the Security is a Global
     Security.

                                      A-1
<PAGE>   56

         THE HOLDER OF THIS DEBENTURE AGREES FOR THE BENEFIT OF THE COMPANY THAT
(A) THIS DEBENTURE AND THE COMMON STOCK ISSUABLE UPON CONVERSION THEREOF MAY BE
OFFERED, RESOLD, PLEDGED OR OTHERWISE TRANSFERRED, ONLY (I) IN THE UNITED STATES
TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL
BUYER (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT) IN A TRANSACTION
MEETING THE REQUIREMENTS OF RULE 144A, (II) OUTSIDE THE UNITED STATES IN AN
OFFSHORE TRANSACTION IN ACCORDANCE WITH RULE 904 UNDER THE SECURITIES ACT, (III)
PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT PROVIDED BY
RULE 144 THEREUNDER (IF AVAILABLE) OR (IV) PURSUANT TO AN EFFECTIVE REGISTRATION
STATEMENT UNDER THE SECURITIES ACT, IN EACH OF CASES (I) THROUGH (IV) IN
ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED
STATES, AND (B) THE HOLDER WILL, AND EACH SUBSEQUENT HOLDER IS REQUIRED TO,
NOTIFY ANY PURCHASER OF THIS DEBENTURE FROM IT OF THE RESALE RESTRICTIONS
REFERRED TO IN (A) ABOVE.](2)

---------

(2)  [These paragraphs to be included only if the Security is a Transfer
     Restricted Security.]

                                      A-2
<PAGE>   57

                           [FORM OF FACE OF SECURITY]

                               EL PASO CORPORATION

             ZERO COUPON CONVERTIBLE DEBENTURE DUE FEBRUARY 28, 2021

Issue Date: February 28, 2001                       Maturity: February 28, 2021

Principal Amount at Maturity: $_________                       CUSIP: 28336LAA7

Original Issue Discount: $547.11                           Issue Price: $452.89
(per $1,000 Principal Amount)                     (per $1,000 Principal Amount)

Registered: No. R-

         El Paso Corporation, a Delaware corporation (the "Company", which term
includes any successor Person under the indenture hereinafter referred to), for
value received, hereby promises to pay to _______________, or registered
assigns, the principal sum of __________________ DOLLARS ($_________) [(or such
greater or lesser amount as is indicated on the Schedule of Exchanges of
Securities on the other side of this Security)](3) on February 28, 2021. The
principal of this Security shall not bear interest, except in the case of
default in payment of principal upon acceleration, redemption, repurchase or
maturity or as specified on the other side of this Security. Original Issue
Discount will accrue as specified on the other side of this Security. This
Security is convertible as specified on the other side of this Security.

         Payment of the principal of and interest, if any, on this Security will
be made at the office or agency of the Company maintained for that purpose in
The City of New York, in such coin or currency of the United States of America
as at the time of payment is legal tender for payment of public and private
debts; provided, however, that at the option of the Company, payment of
interest, if any, may be made by check mailed to the address of the Person
entitled thereto as such address shall appear in the Security Register.
[Payments in respect of this Security shall be made by transfer of immediately
available funds to the account specified by the Holder.](4)

         Reference is hereby made to the further provisions of this Security set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

         Unless the certificate of authentication hereon has been executed by
the Trustee referred to on the reverse hereof by manual signature, this Security
shall not be entitled to any benefit under the Indenture or be valid or
obligatory for any purpose.

---------

(3)  [This language to be included only if the Security is a Global Security.]

(4)  [This sentence should be included only if the Security is a Global
     Security.]

                                      A-3
<PAGE>   58

         IN WITNESS WHEREOF, the Company has caused this Security to be signed
manually or by facsimile by an authorized officer.

Dated:  ___________________

                                                     EL PASO CORPORATION

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

                                      A-4
<PAGE>   59

                     TRUSTEE'S CERTIFICATE OF AUTHENTICATION

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

                                                   THE CHASE MANHATTAN BANK,
                                                       as Trustee

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

                                      A-5
<PAGE>   60

                       [FORM OF REVERSE SIDE OF SECURITY]

                               EL PASO CORPORATION

             ZERO COUPON CONVERTIBLE DEBENTURE DUE FEBRUARY 28, 2021

         This Security is one of a duly authorized issue of senior securities of
the Company (the "Securities"), issued and to be issued in one or more series
under an Indenture, dated as of May 10, 1999, as amended by the Fifth
Supplemental Indenture thereto, dated as of February 28, 2001 (as so amended,
herein called the "Indenture"), between the Company and The Chase Manhattan
Bank, as Trustee (the "Trustee", which term includes any successor trustee under
the Indenture), to which Indenture and all indentures supplemental thereto
reference is hereby made for a statement of the respective rights, limitations
of rights, duties and immunities thereunder of the Company, the Trustee and the
Holders of the Securities and of the terms upon which the Securities are, and
are to be, authenticated and delivered. As provided in the Indenture, the
Securities may be issued in one or more series, which different series may be
issued in various aggregate principal amounts, may mature at different times,
may bear interest, if any, at different rates, may be subject to different
redemption provisions, if any, may be subject to different sinking, purchase or
analogous funds, if any, may be subject to different covenants and Events of
Default and may otherwise vary as in the Indenture provided or permitted. This
Security is one of the series designated on the face hereof, limited in
aggregate Principal Amount at Maturity to $1,766,500,000.00, subject to any
reopening pursuant to Section 301 of the Indenture; provided, however, that if
the Company sells any Securities pursuant to the Option granted to the Initial
Purchaser pursuant to Section 3 of the Purchase Agreement, the Securities of
this series shall be limited in aggregate Principal Amount at Maturity to up to
$441,625,000.00, subject to any reopening pursuant to Section 301 of the
Indenture. Capitalized terms used in this Security but not defined shall have
the meaning assigned to such term in the Indenture.

INTEREST

         This Security shall not bear interest, except as specified in this
paragraph or as described under "Tax Event". If the Principal Amount hereof or
any portion of such Principal Amount is not paid when due (whether upon
acceleration pursuant to Section 502 of the Indenture, upon the date set for
payment of the Redemption Price as described under "Optional Redemption", upon
the date set for payment of the Change in Control Purchase Price pursuant to
"Purchase of Securities at Option of Holder Upon a Change in Control", upon the
date set for payment of the Repurchase Price under "Repurchase by the Company at
the Option of the Holder" or upon the Stated Maturity of this Security) or if
interest due hereon, if any (or any portion of such interest), is not paid when
due, then in each such case the overdue amount shall, to the extent permitted by
law, bear interest at the rate of 4.0% per annum, compounded semi-annually,
which interest shall accrue from the date such overdue amount was originally due
to the date payment of such amount, including interest thereon, has been made or
duly provided for. All such interest shall be payable as set forth in the
Indenture. The accrual of such interest on overdue amounts shall be in lieu of,
and not in addition to, the continued accrual of Original Issue Discount.
Original Issue Discount (the difference between the Issue Price and the
Principal Amount of this Security), in the period during which this Security
remains Outstanding, shall accrue at 4.0% per annum, on a

                                      A-6
<PAGE>   61

semi-annual bond equivalent basis using a 360-day year composed of twelve 30-day
months, from the Issue Date of this Security.

OPTIONAL REDEMPTION

         No sinking fund is provided for the Securities. The Securities are
redeemable as a whole, or from time to time in part, at any time at the option
of the Company at the Redemption Price set forth below, on or after February 28,
2006.

         The table below shows Redemption Prices of a Security of this series
per $1,000 Principal Amount on the dates shown below and at Stated Maturity on
February 28, 2021, which prices reflect accrued Original Issue Discount
calculated through each such date. The Redemption Price of a Security redeemed
between such dates shall include an additional amount reflecting the additional
Original Issue Discount accrued since the immediately preceding date in the
table.

<TABLE>
<CAPTION>
                                                            (1)                 (2)                    (3)
                                                           ISSUE           ACCRUED ORIGINAL      REDEMPTION PRICE
                 REDEMPTION DATE                           PRICE           ISSUE DISCOUNT           (1) + (2)
------------------------------------------------         ----------        -----------------     ----------------
<S>                                                     <C>                 <C>                 <C>
February 28, 2006...............................         $   452.89          $    99.18            $    552.07
February 28, 2007...............................         $   452.89          $   121.48            $    574.37
February 28, 2008...............................         $   452.89          $   144.69            $    597.58
February 28, 2009...............................         $   452.89          $   168.83            $    621.72
February 28, 2010...............................         $   452.89          $   193.95            $    646.84
February 28, 2011...............................         $   452.89          $   220.08            $    672.97
February 28, 2012...............................         $   452.89          $   247.27            $    700.16
February 28, 2013...............................         $   452.89          $   275.56            $    728.45
February 28, 2014...............................         $   452.89          $   304.98            $    757.87
February 28, 2015...............................         $   452.89          $   335.60            $    788.49
February 28, 2016...............................         $   452.89          $   367.46            $    820.35
February 28, 2017...............................         $   452.89          $   400.60            $    853.49
February 28, 2018...............................         $   452.89          $   435.08            $    887.97
February 28, 2019...............................         $   452.89          $   470.95            $    923.84
February 28, 2020...............................         $   452.89          $   508.28            $    961.17
February 28, 2021 (Stated Maturity).............         $   452.89          $   547.11            $  1,000.00
                                                         ----------          ----------            -----------
</TABLE>

         If converted to an interest-bearing debenture following the occurrence
of a Tax Event, this Security will be redeemable at the Restated Principal
Amount plus accrued and unpaid interest from the later of the date of such
conversion and the date on which interest was last past or duly provided for to
the Redemption Date; but in no event will this Security be redeemable before
February 28, 2006.

         If the Company redeems less than all of the outstanding Securities, the
Trustee will select the Securities to be redeemed (i) by lot; (ii) pro rata; or
(iii) by another method the Trustee considers fair and appropriate. If the
Trustee selects a portion of a Holder's Securities for partial redemption and
the Holder converts a portion of the same Securities, the converted portion will
be deemed to be from the portion selected for redemption. Upon any redemption of
less than all the Securities of this Series, the Company and the Trustee may
treat as Outstanding Securities of this series surrendered for conversion during
the period 15 days next preceding the mailing of a

                                      A-7
<PAGE>   62

notice of redemption and need not treat as Outstanding any Security of this
series authenticated and delivered during such period in exchange for the
unconverted portion of any Security of this series converted in part during such
period.

NOTICE OF REDEMPTION

         Notice of redemption will be mailed by first-class mail not less than
15 days but not more than 60 days before the Redemption Date to each Holder of
Securities to be redeemed at its registered address. Securities of this series
in denominations larger than $1,000 Principal Amount at Maturity may be redeemed
in part, but only in whole multiples of $1,000. On and after the Redemption
Date, subject to the deposit with the Paying Agent of funds sufficient to pay
the Redemption Price, Original Issue Discount (or interest, if this Security is
converted to an interest-bearing debenture) ceases to accrue on Securities of
this series or portions thereof called for redemption.

PURCHASE OF SECURITIES AT OPTION OF HOLDER UPON A CHANGE IN CONTROL

         At the option of the Holder and subject to the terms and conditions of
the Indenture, the Company shall become obligated to purchase all or any part
specified by the Holder (so long as the Principal Amount at Maturity of such
part is $1,000 or an integral multiple of $1,000 in excess thereof) of this
Security on the date that is 35 Business Days after the occurrence of a Change
in Control, at a Change in Control Purchase Price equal to the Issue Price plus
accrued Original Issue Discount through the Change in Control Purchase Date. The
Holder shall have the right to withdraw any Change in Control Purchase Notice
(in whole or in a portion thereof that is $1,000 Principal Amount at Maturity or
an integral multiple of $1,000 in excess thereof) at any time prior to the close
of business on the Business Day prior to the Change in Control Purchase Date by
delivering a written notice of withdrawal to the Paying Agent in accordance with
the terms of the Indenture.

         If prior to a Change in Control Purchase Date this Security has been
converted to an interest-bearing debenture following the occurrence of a Tax
Event, the Change in Control Purchase Price shall be equal to the Restated
Principal Amount plus accrued and unpaid interest from the later of the date of
conversion and the date on which interest was last paid or provided for to the
Change in Control Purchase Date.

CONVERSION

         A Holder of this Security may convert the Security into shares of
Common Stock, so long as the conditions described in Section 1402 of the
Indenture are met, at any time until the close of business on the Business Day
prior to the Stated Maturity; provided, however, that if the Security is called
for redemption, the conversion right will terminate at the close of business on
the Business Day immediately preceding the Redemption Date for such Security or
such earlier date as the Holder presents such Security for redemption (unless
the Company shall default in making the redemption payment when due, in which
case the conversion right shall terminate at the close of business on the date
such default is cured and such Security is redeemed). A Security in respect of
which a Holder has delivered a Repurchase Notice or Change in Control Purchase
Notice exercising the option of such Holder to require the Company to purchase
such Security

                                      A-8
<PAGE>   63

may be converted only if such notice of exercise is withdrawn in accordance with
the terms of the Indenture. The initial Conversion Rate is 4.7872 shares of
Common Stock per $1,000 Principal Amount at Maturity, subject to adjustment in
certain events described in the Indenture. The Company will deliver cash or a
check in lieu of any fractional share of Common Stock.

         If the Company exercises its option pursuant to Section 1701 of the
Indenture to have interest in lieu of Original Issue Discount accrue on this
Security following a Tax Event, the Holder will be entitled on conversion to
receive the same number of shares of Common Stock such Holder would have
received if the Company had not exercised such option. If the Company exercises
such option, Securities surrendered for conversion during the period from the
close of business on any Regular Record Date immediately preceding any Interest
Payment Date to the opening of business of such Interest Payment Date (unless
such Securities or portions thereof have been called for redemption on a
Redemption Date within such period) must be accompanied by payment from the
Holder of an amount equal to the interest thereon that the registered Holder is
to receive from the Company on such Interest Payment Date. Except where
Securities surrendered for conversion must be accompanied by payment as
described above, no interest on converted Securities will be payable by the
Company on any Interest Payment Date subsequent to the date of conversion.

         A Holder may convert a portion of this Security if the Principal Amount
at Maturity of such portion is $1,000 or an integral multiple of $1,000. No
payment or adjustment will be made for dividends on the Common Stock except as
provided in the Indenture. On conversion of this Security, that portion of
accrued Original Issue Discount (and interest if the Security is converted to an
interest-bearing debenture) attributable to the period from the Issue Date (or,
in the case of interest, if the Company has exercised the option referred to in
"Tax Event", the later of (x) the Option Exercise Date and (y) the date on which
interest was last paid or duly provided for) through the Conversion Date with
respect to the converted Security shall not be cancelled, extinguished or
forfeited, but rather shall be deemed to be paid in full to the Holder thereof
through the delivery of the Common Stock (together with the cash payment, if
any, in lieu of fractional shares) in exchange for the Security being converted
pursuant to the terms hereof; and the fair market value of such shares of Common
Stock (together with any such cash payment in lieu of fractional shares) shall
be treated as issued, to the extent thereof, first in exchange for Original
Issue Discount (and unpaid interest, if the Company has exercised its option
provided for in "Tax Event") accrued through the Conversion Date, and the
balance, if any, of such fair market value of such Common Stock (and any such
cash payment) shall be treated as issued in exchange for the Issue Price (or
Restated Principal Amount, if the Company has exercised its option provided for
in "Tax Event") of the Security being converted pursuant to the provisions
hereof.

         No fractional shares will be issued upon conversion; in lieu thereof,
an amount will be paid in cash based upon the closing price of the Common Stock
on the Trading Day immediately prior to the Conversion Date.

         To convert a Security, a Holder must (a) complete and manually sign the
conversion notice set forth below and deliver such notice to a Conversion Agent,
(b) surrender the Security to the Conversion Agent, (c) furnish appropriate
endorsements and transfer documents (including

                                      A-9
<PAGE>   64

any certification that may be required under applicable law) if required by the
Conversion Agent, and (d) pay any transfer or similar tax, if required.

REPURCHASE BY THE COMPANY AT THE OPTION OF THE HOLDER

         Subject to the terms and conditions of the Indenture, the Company shall
become obligated to purchase, at the option of the Holder, this Security on the
following Repurchase Dates and at the following Repurchase Prices per $1,000
Principal Amount at Maturity, upon delivery of a Repurchase Notice containing
the information set forth in the Indenture, at any time from the opening of
business on the date that is 20 Business Days prior to such Repurchase Date
until the close of business on the Business Day next preceding such Repurchase
Date and upon delivery of this Security to the Paying Agent by the Holder as set
forth in the Indenture.

<TABLE>
<CAPTION>
                       REPURCHASE DATE                        REPURCHASE PRICE
               --------------------------------------         ----------------
<S>                                                           <C>
               February 28, 2006.....................             $552.07
               February 28, 2011.....................             $672.97
               February 28, 2016.....................             $820.35
</TABLE>

         The Repurchase Price (equal to the Issue Price plus accrued Original
Issue Discount through the Repurchase Date) may be paid, at the option of the
Company, in cash or by the issuance of Common Stock (as provided in the
Indenture), or in any combination thereof.

         If prior to a Repurchase Date this Security has been converted to an
interest-bearing debenture following the occurrence of a Tax Event, the
Repurchase Price will be equal to the Restated Principal Amount plus accrued and
unpaid interest from the date of conversion to the Repurchase Date.

         Holders have the right to withdraw any Repurchase Notice by delivering
to the Paying Agent a written notice of withdrawal prior to the close of
business on the Business Day next preceding the Repurchase Date in accordance
with the provisions of the Indenture.

         If cash (and/or securities if permitted under the Indenture) sufficient
to pay the Repurchase Price of all Securities or portions thereof to be
purchased as of the Repurchase Date, is deposited with the Paying Agent on the
Business Day following the Repurchase Date, such Securities shall cease to be
Outstanding, Original Issue Discount (or interest, if this Security has been
converted to an interest-bearing debenture following the occurrence of a Tax
Event) ceases to accrue on such Securities (or portions thereof) immediately
after such Repurchase Date, and the Holder thereof shall have no other rights as
such (other than the right to receive the Repurchase Price upon surrender of
such Security).

TAX EVENT

         From and after (i) the date (the "Tax Event Date") of the occurrence of
a Tax Event and (ii) the date the Company exercises such option, at the option
of the Company, whichever is later (the "Option Exercise Date"), interest in
lieu of future Original Issue Discount shall accrue at the rate of 4.0% per
annum on a Principal Amount at Maturity per Security (the "Restated Principal

                                      A-10
<PAGE>   65

Amount") equal to the Issue Price plus Original Issue Discount accrued through
the Option Exercise Date and shall be payable semi-annually on February 28 and
August 28 of each year (each an "Interest Payment Date") to holders of record at
the close of business on February 15 or August 15 (each a "Regular Record Date")
immediately preceding such Interest Payment Date. Interest will be computed on
the basis of a 360-day year comprised of twelve 30-day months and will accrue
from the most recent date to which interest has been paid or duly provided for
or, if no interest has been paid or duly provided for, from the Option Exercise
Date.

         Interest on any Security that is payable, and is punctually paid or
duly provided for, on any Interest Payment Date shall be paid to the person in
whose name that Security is registered at the close of business on the Regular
Record Date.

         Except as otherwise specified with respect to the Securities, any
Defaulted Interest on any Security shall forthwith cease to be payable to the
registered Holder thereof on the relevant Regular Record Date by virtue of
having been such Holder, and such Defaulted Interest may be paid by the Company
as provided for in Section 307 of the Indenture.

CONVERSION ARRANGEMENT ON CALL FOR REDEMPTION

         Any Securities of this series called for redemption, unless surrendered
for conversion before the close of business on the Redemption Date, may be
deemed to be purchased from the Holders of such Securities at an amount not less
than the Redemption Price, by one or more investment bankers or other purchasers
who may agree with the Company to purchase such Securities from the Holders, to
convert them into Common Stock of the Company and to make payment for such
Securities to the Paying Agent in trust for such Holders.

TRANSFER

         As provided in the Indenture and subject to certain limitations therein
set forth, the transfer of this Security is registrable in the Security
Register, upon surrender of this Security for registration or transfer at the
office or agency in a place of payment for Securities of this series, duly
endorsed by, or accompanied by a written instrument of transfer in form
satisfactory to the Company and the Security Registrar duly executed by, the
Holder hereof or his attorney duly authorized in writing, and thereupon one or
more new Securities of this series, of any authorized denominations and for the
same aggregate principal amount, executed by the Company and authenticated and
delivered by the Trustee, will be issued to the designated transferee or
transferees.

         The Securities of this series are issuable only in registered form
without coupons in denominations of $1,000 Principal Amount at Maturity and any
integral multiple thereof. As provided in the Indenture and subject to certain
limitations set forth therein and on the face of this Security, Securities of
this series are exchangeable for a like aggregate principal amount of Securities
of this series of a different authorized denomination as requested by the Holder
surrendering the same.

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

                                      A-11
<PAGE>   66

         Prior to due presentment of this Security for registration of transfer,
the Company, the Trustee or any agent of the Company or the Trustee may treat
the Person in whose name this Security is registered as the owner hereof for all
purposes, whether or not this Security be overdue, and neither the Company, the
Trustee nor any such agent shall be affected by notice to the contrary.

AMENDMENT, SUPPLEMENT AND WAIVER

         Subject to certain exceptions and limitations, the Indenture or the
Securities may be amended or supplemented with the consent of the Holders of at
least a majority in principal amount of the then Outstanding Securities of all
series of Securities affected by such amendment or supplement (acting as one
class), and any existing or past Default or Event of Default under, or
compliance with any provision of, the Indenture may be waived (other than any
continuing Default or Event of Default in the payment of the principal of or
interest on the Securities) by the Holders of at least a majority in principal
amount of the then Outstanding Securities of any series or of all series (acting
as one class) in accordance with the terms of the Indenture. Without the consent
of any Holder, the Company and the Trustee may amend or supplement the Indenture
or the Securities, to secure the Securities pursuant to the requirements of
Section 1006 of the Indenture or otherwise; to evidence the succession of
another Person to the Company, and the assumption by any such successor of the
covenants in the Indenture and in the Securities; to add to the covenants of the
Company or the Events of Default for the benefit of the Holders of all or any
series of the Securities, or to surrender any right or power conferred by the
Indenture upon the Company; to add to, change or eliminate any of the provisions
of the Indenture in respect of any one or more series of Securities, provided
that any such addition, change or elimination shall become effective only when
there is no Security Outstanding of any series created prior to execution of
such supplemental indenture which is entitled to the benefit of such provision;
to establish the form or terms of Securities as permitted by the Indenture; to
cure any ambiguity, to correct or supplement any provision herein which may be
inconsistent with any other provision herein, to comply with any applicable
mandatory provisions of law or to make any other provisions with respect to
matters or questions arising under the Indenture, provided that such action
shall not adversely affect the interests of the Holders of Securities of any
series in any material respect; to evidence and provide for the acceptance of
appointment by a successor Trustee with respect to the Securities of one or more
series and to add to or change any of the provisions of the Indenture as shall
be necessary to provide for or facilitate the administration of the trusts by
more than one Trustee, pursuant to the requirements of Section 611 of the
Indenture; to modify, eliminate or add to the provisions of the Indenture to
such extent as shall be necessary to effect the qualification of the Indenture
under the Trust Indenture Act or under any similar federal statute subsequently
enacted, and to add to the Indenture such other provisions as may be expressly
required under the Trust Indenture Act; and to make provision with respect to
the conversion rights of this Security pursuant to the requirements of Article
FOURTEEN of the Indenture.

         The right of any Holder to participate in any consent required or
sought pursuant to any provision of the Indenture (and the obligation of the
Company to obtain any such consent otherwise required from such Holder) may be
subject to the requirement that such Holder shall have been the Holder of record
of any Securities with respect to which such consent is required or sought as of
a date fixed in accordance with the terms of the Indenture.

                                      A-12
<PAGE>   67

         Without the consent of each Holder affected, the Company may not (i)
change the Stated Maturity of the principal of, or any installment of principal
of or interest, if any, on, any Security, or reduce the principal amount thereof
or premium, if any, on or the rate of interest thereon; (ii) reduce the
percentage in principal amount of the Outstanding Securities of any series, the
consent of whose Holders is required for any such supplemental indenture, or the
consent of whose Holders is required for any waiver (of compliance with certain
provisions of this Indenture or certain defaults hereunder and their
consequences) provided for in the Indenture; (iii) change any obligation of the
Company, with respect to Outstanding Securities of a series, to maintain an
office or agency in the places and for the purposes specified in Section 1002 of
the Indenture for such series; (iv) modify any of the provisions of Section 902,
Section 513 or Section 1008 of the Indenture, except to increase any such
percentage or to provide that certain other provisions of the Indenture cannot
be modified or waived without the consent of the Holder of each Outstanding
Security affected thereby; provided, however, that this clause shall not be
deemed to require the consent of any Holder with respect to changes in the
references to "the Trustee" and concomitant changes, or the deletion of this
proviso, in accordance with the requirements of Sections 611 and 901(7) of the
Indenture; or (v) adversely affect the right to convert this Security as
provided in Article FOURTEEN of the Indenture, or adversely affect the right to
require the Company to repurchase this Security as provided in Article FIFTEEN
or Article SIXTEEN of the Indenture.

         A supplemental indenture that changes or eliminates any covenant or
other provision of the Indenture which has expressly been included solely for
the benefit of one or more particular series of Securities under the Indenture,
or which modifies the rights of the Holders of Securities of such series with
respect to such covenant or other provision, shall be deemed not to affect the
rights under the Indenture of the Holders of Securities of any other series.

SUCCESSOR PERSON

         When a successor person assumes all the obligations of its predecessor
under the Securities and the Indenture in accordance with the terms and
conditions of the Indenture, the predecessor person will (except in certain
circumstances specified in the Indenture) be released from those obligations.

DEFAULTS AND REMEDIES

         Events of Default are defined in the Indenture and generally include:
(i) default by the Company in the payment of any interest upon the Securities of
this series, when it becomes due and payable, after conversion to
interest-bearing Securities pursuant to Section 1701 of the Indenture, or in the
payment of Additional Interest when it becomes due and payable, and continuance
of any such default for a period of 30 days; (ii) default by the Company in
payment of the Principal Amount at Maturity (or, if the Securities of this
series have been converted to interest-bearing Securities pursuant to Section
1701 of the Indenture following a Tax Event, the Restated Principal Amount), the
Issue Price plus accrued Original Issue Discount, the Redemption Price,
Repurchase Price or Change in Control Purchase Price, as the case may be, in
respect of the Securities of this series when the same becomes due and payable;
(iii) default by the Company in compliance with any of its other covenants or
agreements in, or provisions of, the Securities or in the Indenture which shall
not have been remedied within 60 days after written

                                      A-13
<PAGE>   68

notice by the Trustee or by the holders of at least 25% in principal amount of
the Securities of the relevant series then outstanding; or (iv) certain events
involving bankruptcy, insolvency or reorganization of the Company. If an Event
of Default occurs and is continuing, the Trustee or the Holders of at least 25%
in principal amount of the then outstanding Securities of the series affected by
such default may declare the principal of and interest on all the Securities of
that series to be immediately due and payable. The portion of the Principal
Amount of each Security of this series that shall become due upon the
acceleration is equal to the Issue Price plus accrued Original Issue Discount on
such Security or, if such Security has been converted to an interest-bearing
Security, the Restated Principal Amount plus accrued and unpaid interest from
the later of the date of conversion and the date on which interest was last paid
or duly provided for. Holders may not enforce the Indenture or the Securities
except as provided in the Indenture. The Trustee may require indemnity
reasonably satisfactory to it before it enforces the Indenture or the
Securities. Subject to certain limitations, Holders of a majority in principal
amount of the then outstanding Securities of this series may direct the Trustee
in its exercise of any trust or power with respect to such series. The Trustee
may withhold from Holders notice of any continuing default (except a default in
payment of principal or interest) if it determines that withholding notice is in
their interests. The Company must furnish an annual compliance certificate to
the Trustee.

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

DISCHARGE PRIOR TO MATURITY

         The Indenture provides that the Company (a) will be discharged from any
and all obligations in respect of the Securities (except for certain obligations
described in the Indenture), or (b) need not comply with certain restrictive
covenants of the Indenture, in each case if the Company deposits, in trust, with
the Trustee money or U.S. Government Obligations (or a combination thereof)
which through the payment of interest thereon and principal thereof in
accordance with their terms will provide money, in an amount sufficient to pay
all the principal of and interest on the Securities, but such money need not be
segregated from other funds except to the extent required by law.

NO RECOURSE AGAINST OTHERS

         No recourse under or upon any obligation, covenant or agreement of or
contained in the Indenture or of or contained in any Security, or for any claim
based thereon or otherwise in respect thereof, or in any Security, or because of
the creation of any indebtedness represented thereby, shall be had against any
incorporator, stockholder, officer or director, as such, past, present or
future, of the Company or of any successor Person, either directly or through
the Company or any successor Person, whether by virtue of any constitution,
statute or rule of law, or by the enforcement of any assessment, penalty or
otherwise; it being expressly understood that all such liability is hereby
expressly waived and released by the acceptance hereof and as a condition of,
and as part of the consideration for, the Securities and the execution of the
Indenture.

                                      A-14
<PAGE>   69

AUTHENTICATION

         This Security shall not be valid until authenticated by the manual
signature of the Trustee or an authenticating agent.

INDENTURE TO CONTROL; GOVERNING LAW

         In the case of any conflict between the provisions of this Security and
the Indenture, the provisions of the Indenture shall control.

         THE INDENTURE AND THE SECURITIES SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT GIVING EFFECT TO
APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THE LAWS OF ANOTHER
JURISDICTION WOULD BE REQUIRED THEREBY.

ABBREVIATIONS AND DEFINITIONS

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

         All terms defined in the Indenture and used in this Security but not
specifically defined herein are defined in the Indenture and are used herein as
so defined.

                                      A-15
<PAGE>   70

                                CONVERSION NOTICE

         To convert this Security into Common Stock of the Company, check the
box: [ ]

         To convert only part of this Security, state the Principal Amount at
Maturity to be converted (must be $1,000 or a multiple of $1,000):
$______________.

         If you want the stock certificate made out in another person's name,
fill in the form below:

--------------------------------------------------------------------------------
                (Insert other person's soc. sec. or tax I.D. no.)

--------------------------------------------------------------------------------
            (Print or type other person's name, address and zip code)

Your Signature:                               Date:
                ---------------------------         ----------------------------
(Sign exactly as your name appears on the other side of this Security)

*Signature guaranteed by:
                          ------------------------------------------------------

By:
    ---------------------------------

---------
         *The signature must be guaranteed by an institution which is a member
of one of the following recognized signature guaranty programs: (i) the
Securities Transfer Agent Medallion Program (STAMP); (ii) the New York Stock
Exchange Medallion Program (MSP); (iii) the Stock Exchange Medallion Program
(SEMP); or (iv) such other guaranty program acceptable to the Trustee.

                                      A-16
<PAGE>   71

             OPTION OF HOLDER TO ELECT PURCHASE ON CHANGE IN CONTROL

         If you want to elect to have this Security purchased, in whole or in
part, by the Company pursuant to Section 1601 of the Indenture, check the
following box: [ ]

         If you want to have only part of this Security purchased by the Company
pursuant to Section 1601 of the Indenture, state the Principal Amount at
Maturity that you want to be purchased (must be $1,000 or a multiple of $1,000):
$
 ----------------

Your Signature:                               Date:
                ---------------------------         ----------------------------
(Sign exactly as your name appears on the other side of this Security)

*Signature guaranteed by:
                          ------------------------------------------------------

By:
    ---------------------------------

---------

         *The signature must be guaranteed by an institution which is a member
of one of the following recognized signature guaranty programs: (i) the
Securities Transfer Agent Medallion Program (STAMP); (ii) the New York Stock
Exchange Medallion Program (MSP); (iii) the Stock Exchange Medallion Program
(SEMP); or (iv) such other guaranty program acceptable to the Trustee.

                                      A-17
<PAGE>   72

                      SCHEDULE OF EXCHANGES OF SECURITIES(5)

         The following exchanges, redemptions, repurchases or conversions of a
part of this Global Security have been made:

<TABLE>
<CAPTION>
                           AMOUNT OF DECREASE IN         AMOUNT OF INCREASE IN
                          PRINCIPAL AMOUNT OF THIS      PRINCIPAL AMOUNT OF THE
DATE OF TRANSACTION          GLOBAL SECURITY                GLOBAL SECURITY
-------------------       ------------------------      -----------------------
<S>                       <C>                           <C>
</TABLE>

---------

(5)  This Schedule should be included only if the Security is a Global Security.

                                      A-18
<PAGE>   73

          CERTIFICATE TO BE DELIVERED UPON EXCHANGE OR REGISTRATION OF
                       TRANSFER OF RESTRICTED SECURITIES(6)

         Re:   Zero Coupon Convertible Debentures Due February [ ], 2021 (the
               "Securities") of El Paso Corporation.

         This certificate relates to $_________ Principal Amount at Maturity of
Securities owned in (check applicable box)

         [ ] Book-entry or

         [ ] definitive form

by                                      (the "Transferor").
   ------------------------------------

         The Transferor has requested a Registrar or the Trustee to exchange or
register the transfer of such Securities.

         In connection with such request and in respect of each such Security,
the Transferor does hereby certify that the Transferor is familiar with transfer
restrictions relating to the Securities as provided in Section 102 of the Fifth
Supplemental Indenture dated as of February [ ], 2001 to the Indenture, dated as
of May 10, 1999 (as so amended and supplemented, the "Indenture"), between El
Paso Corporation and The Chase Manhattan Bank.

         In connection with any transfer of any of the Securities evidenced by
this certificate occurring prior to the expiration of the period referred to in
Rule 144(k) under the Securities Act after the later of the date of original
issuance of such Securities and the last date, if any, on which such Securities
were owned by the Company or any Affiliate of the Company, the undersigned
confirms that such Securities are being transferred in accordance with its
terms:

CHECK ONE BOX BELOW

         (1)     [ ]       to the Transferor in an exchange for an equal
                           Principal Amount of Securities of other
                           denominations as set forth in the attached
                           instruction; or

         (2)     [ ]       to the Company; or

         (3)     [ ]       pursuant to an effective registration statement
                           under the Securities Act of 1933; or

         (4)     [ ]       inside the United States to a "qualified
                           institutional buyer" (as defined in Rule 144A under
                           the Securities Act of 1933) that purchases for its
                           own account or for the account of a qualified
                           institutional buyer to whom notice is given that such
                           transfer is being made in reliance on Rule 144A,

---------
(6)  This certificate should only be included if this Security is a Transfer
     Restricted Security.

                                      A-19
<PAGE>   74

                           in each case pursuant to and in compliance with
                           Rule 144A under the Securities Act of 1933; or

         (5)     [ ]       outside the United States in an offshore
                           transaction within the meaning of Regulation S under
                           the Securities Act in compliance with Rule 904 under
                           the Securities Act of 1933; or

         (6)     [ ]       pursuant to an exemption from the registration
                           requirements of the Securities Act of 1933 in
                           accordance with Rule 144 under the Securities Act of
                           1933, or pursuant to another available exemption from
                           the registration requirements of the Securities Act
                           of 1933 (other than pursuant to Rule 144A or Rule 144
                           under the Securities Act of 1933) as a result of
                           which such Securities shall cease to be a restricted
                           security within the meaning of Rule 144.

Unless one of the boxes is checked, the Trustee will refuse to register any of
the Securities evidenced by this certificate in the name of any person other
than the registered holder thereof; provided, however, that if box (5) or (6) is
checked, the Trustee may require, prior to registering any such transfer of the
Securities, such legal opinions, certifications and other information as the
Company has reasonably requested to confirm that such transfer is being made
pursuant to an exemption from, or in a transaction not subject to, the
registration requirements of the Securities Act of 1933, such as the exemption
provided by Rule 144 under such Act.

                                                 -------------------------------
                                                 Signature

Signature Guarantee:

------------------------------------             -------------------------------
Signature must be guaranteed                     Signature

              TO BE COMPLETED BY PURCHASER IF (3) ABOVE IS CHECKED.

         The undersigned represents and warrants that it is purchasing this
Security for its own account or an account with respect to which it exercises
sole investment discretion and that it and any such account is a "qualified
institutional buyer" within the meaning of Rule 144A under the Securities Act of
1933, and is aware that the sale to it is being made in reliance on Rule 144A
and acknowledges that it has received such information regarding the Company as
the undersigned has requested pursuant to Rule 144A or has determined not to
request such information and that it is aware that the transferor is relying
upon the undersigned's foregoing representations in order to claim the exemption
from registration provided by Rule 144A.

Dated:                                       -----------------------------------
      -------------------------------        NOTICE:  To be executed by an
                                                      executive officer

                                      A-20

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