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                                                                     Exhibit 4.1


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                          FIRST SUPPLEMENTAL INDENTURE


                                     BETWEEN


                                PERKINELMER, INC.

                                       AND


                          BANK ONE TRUST COMPANY, N.A.



                                 AUGUST 7, 2000

                                  TO INDENTURE
                           DATED AS OF AUGUST 7, 2000
                           PROVIDING FOR THE ISSUANCE
                         OF SENIOR SECURITIES IN SERIES




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                                TABLE OF CONTENTS



ARTICLE ONE - THE 2020 DEBENTURES........................................    2

   SECTION 101. DESIGNATION OF 2020 DEBENTURES; ESTABLISHMENT OF FORM....    2
   SECTION 102. AMOUNT...................................................    3
   SECTION 103. ACCRUAL OF ORIGINAL ISSUE DISCOUNT; INTEREST.............    3
   SECTION 104. DENOMINATIONS............................................    3
   SECTION 105. PLACE OF PAYMENT.........................................    3
   SECTION 106. REDEMPTION...............................................    3
   SECTION 107. DISCHARGE OF LIABILITY ON 2020 DEBENTURES................    4
   SECTION 108. CONVERSION...............................................    4
   SECTION 109. MATURITY.................................................    4
   SECTION 110. REPURCHASE...............................................    4
   SECTION 111. AMOUNT DUE UPON EVENT OF DEFAULT.........................    4
   SECTION 112. OTHER TERMS OF 2020 DEBENTURES...........................    5

ARTICLE TWO - AMENDMENTS TO THE INDENTURE................................    5

   SECTION 201. DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION..    5
   SECTION 202. REGISTRATION, REGISTRATION OF TRANSFER AND EXCHANGE......    9
   SECTION 203. MUTILATED, DESTROYED, LOST AND STOLEN SECURITIES.........    9
   SECTION 204. PAYMENT OF INTEREST; INTEREST RIGHTS PRESERVED...........    9
   SECTION 205. CANCELLATION.............................................   10
   SECTION 206. EVENTS OF DEFAULT; UNCONDITIONAL RIGHT OF HOLDERS TO
                RECEIVE PRINCIPAL, PREMIUM AND INTEREST..................   10
   SECTION 207. THE TRUSTEE..............................................   11
   SECTION 208. CONSOLIDATION............................................   11
   SECTION 209. SUPPLEMENTAL INDENTURES..................................   11
   SECTION 210. EXECUTION OF SUPPLEMENTAL INDENTURES.....................   12
   SECTION 211. MAINTENANCE OF OFFICE OR AGENCY..........................   12
   SECTION 212. COVENANTS................................................   12
   SECTION 213. REDEMPTION...............................................   12
   SECTION 214. COUNTERPARTS.............................................   13
   SECTION 215. CONVERSION...............................................   13
   SECTION 216. REPURCHASE AT OPTION OF HOLDER; REPURCHASE UPON CHANGE
                IN CONTROL; TAX EVENTS...................................   24

ARTICLE THREE - MISCELLANEOUS............................................   39

   SECTION 301. INTEGRAL PART............................................   39
   SECTION 302. GENERAL DEFINITIONS......................................   39
   SECTION 303. ADOPTION, RATIFICATION AND CONFIRMATION..................   39


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   SECTION 304. COUNTERPARTS.............................................   39
   SECTION 305. GOVERNING LAW............................................   39

ANNEX A - FORM OF 2020 DEBENTURE



















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                                PERKINELMER, INC.
                          FIRST SUPPLEMENTAL INDENTURE

     THIS FIRST SUPPLEMENTAL INDENTURE, dated as of August 7, 2000, between
PerkinElmer, Inc. (formerly, EG&G, Inc.), a Massachusetts corporation (the
"Company") and Bank One Trust Company, N.A. (the "Trustee").


                               W I T N E S S E T H


     WHEREAS, the Company has executed and delivered to the Trustee an
Indenture, of even date herewith (the "Indenture").

     WHEREAS, the Indenture provides for the Company's issuance from time to
time of senior unsecured debt securities;

     WHEREAS, no Securities have heretofore been issued under the indenture and
no securityholders currently exist thereunder;

     WHEREAS, Article Nine of the Indenture provides that the Company, when
authorized by or pursuant to a Board Resolution, and the Trustee may without the
consent of any Securityholders enter into one or more indentures supplemental to
the Indenture to establish the form and terms of Securities of any series,
including redemption, conversion and repurchase terms and procedures;

     WHEREAS, the Company desires to issue a series of zero coupon senior
convertible debentures due August 7, 2020 under the Indenture, and has duly
authorized the creation and issuance of such debentures and the execution and
delivery of this Supplemental Indenture to modify the Indenture and provide
certain additional provisions as hereinafter described;

     WHEREAS, the Company and the Trustee deem it advisable to enter into this
Supplemental Indenture for the purpose of establishing the terms of such
convertible subordinated debt securities and providing for the rights,
obligations and duties of the Trustee with respect to such debt securities;

     WHEREAS, concurrent with the execution hereof, the Company has delivered an
Officer's Certificate and has caused its counsel to deliver to the Trustee an
Opinion of Counsel or a reliance letter upon an Opinion of Counsel to the effect
that the execution of this Supplemental Indenture is authorized or permitted by
the Indenture;

     WHEREAS, all conditions and requirements of the Indenture necessary to make
this Supplemental Indenture a valid, binding and legal instrument in accordance
with its terms have been performed and fulfilled by the parties hereto.


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     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 Securities as follows:

                                   ARTICLE ONE
                              THE 2020 DEBENTURES

SECTION 101. DESIGNATION OF 2020 DEBENTURES; ESTABLISHMENT OF FORM.

     There shall be a series of Securities designated "Zero Coupon Convertible
Debentures Due August 7, 2020" of the Company (the "2020 Debentures"), 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 First Supplemental
Indenture, in each case with such appropriate insertions, omissions,
substitutions and other variations as are required or permitted by the
Indenture, and which 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 2020 Debentures, as evidenced by their execution of the 2020 Debentures.

     The 2020 Debentures will initially be issued in permanent global form,
substantially in the form set forth in Annex A hereto (the "Global Securities"),
as a Book-Entry Security. Each Global Security shall represent such of the
Outstanding 2020 Debentures as shall be specified therein and shall provide that
it shall represent the aggregate amount of Outstanding 2020 Debentures from time
to time endorsed thereon and that the aggregate amount of Outstanding 2020
Debentures represented thereby may from time to time be reduced to reflect
exchanges conversions, repurchases and redemptions. Any endorsement of a Global
Security to reflect the amount, or any increase or decrease in the amount, of
Outstanding 2020 Debentures represented thereby shall be made by the Trustee in
accordance with written instructions or such other written form of instructions
as is customary for the Depositary, from the Depositary or its nominee on behalf
of any Person having the beneficial interest in the Global Security.

     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 its agent, Paying
Agent and Conversion Agent, pursuant to Section 1002 of the Indenture, with
respect to the 2020 Debentures.


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SECTION 102. AMOUNT.

     (a) The Trustee shall authenticate and deliver 2020 Debentures for original
issue in an aggregate Principal Amount of up to $920,737,000 upon Company Order
for the authentication and delivery of 2020 Debentures, without any further
action by the Company. The aggregate Principal Amount of 2020 Debentures that
may be authenticated and delivered under the Indenture may not exceed the amount
set forth in the foregoing sentence, except for 2020 Debentures authenticated
and delivered upon registration of transfer of, or in exchange for, or in lieu
of, other 2020 Debentures pursuant to Section 304, 305, 306, 906, 1107, 1403 or
1511 of the Indenture.

     (b) The Company may not issue new 2020 Debentures to replace 2020
Debentures that it has paid or delivered to the Trustee for cancellation or that
any Holder has converted pursuant to Article Fourteen of the Indenture.

SECTION 103. ACCRUAL OF ORIGINAL ISSUE DISCOUNT; INTEREST.

     The 2020 Debentures shall be Original Issue Discount Securities. Original
Issue Discount shall accrue with respect to the 2020 Debentures at the rate set
forth under the caption "Interest" in the 2020 Debentures, commencing on the
Issue Date of the 2020 Debentures. Except as provided under the caption "Tax
Event" in the 2020 Debentures and in Article Sixteen of the Indenture, there
shall be no periodic payments of interest on the 2020 Debentures.

SECTION 104. DENOMINATIONS.

     The 2020 Debentures shall be in fully registered form without coupons in
denominations of $1,000 of Principal Amount or any integral multiple thereof.

SECTION 105. PLACE OF PAYMENT.

     The Place of Payment for the 2020 Debentures and the place or places where
the 2020 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 2020 Debentures is at the office of the Trustee in New
York, New York and at the agency of the Trustee maintained for that purpose at
the office of the Trustee; provided 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).

SECTION 106. REDEMPTION.

     (a) There shall be no sinking fund for the retirement of the 2020
Debentures.


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     (b) The Company, at its option, may redeem the 2020 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 2020
Debentures and in accordance with the provisions of the Indenture, including,
without limitation, Article Eleven thereof.

SECTION 107. DISCHARGE OF LIABILITY ON 2020 DEBENTURES.

     Article 13 of the Indenture shall be applicable to the 2020 Debentures.

SECTION 108. CONVERSION.

     The 2020 Debentures shall be convertible in accordance with the provisions
and at the conversion price set forth under the caption "Conversion" in the 2020
Debentures and in accordance with the provisions of the Indenture, including,
without limitation, Article Fourteen thereof.

SECTION 109. MATURITY.

     The date on which the principal of the 2020 Debentures is payable pursuant
to the Indenture, except as otherwise provided in the 2020 Debenture shall be
August 7, 2020. The Stated Maturity of the 2020 Debentures is August 7, 2020.

SECTION 110. REPURCHASE.

     (a) The 2020 Debentures shall be repurchased by the Company in accordance
with the provisions and at the Repurchase Prices set forth under the caption
"Repurchase by the Company at the Option of the Holder" in the 2020 Debentures
and in accordance with the provisions of the Indenture, including, without
limitation, Article Fifteen thereof.

     (b) The Company, at the option of the Holders thereof, shall repurchase the
2020 Debentures 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 2020 Debentures and in
accordance with the provisions of the Indenture, including, without limitation,
Article Fifteen thereof.


SECTION 111. AMOUNT DUE UPON EVENT OF DEFAULT.

     If an Event of Default with respect to any 2020 Debentures that are at the
time Outstanding occurs and is continuing, then in accordance with Section 502
of the Indenture, the


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Trustee or the Holders of not less than 25% in principal amount of the
Outstanding 2020 Debentures may declare all unpaid Issue Price plus accrued
Original Issue Discount through the acceleration date, if any (or, if the 2020
Debentures have been converted to interest-bearing 2020 Debentures pursuant to
Section 1601 of the Indenture, the Restated Principal Amount plus accrued and
unpaid interest, if any, from the date of conversion to the acceleration date),
of all of the 2020 Debentures to be due and payable immediately by a notice in
writing to the Company (and to the Trustee if given by Holders), and upon any
such declaration such specified amount shall become immediately due and payable.
If an Event of Default described in clause (6) or (7) of Section 501 of the
Indenture shall occur, such specified amount of all Outstanding 2020 Debentures
ipso facto shall become and be immediately due and payable without any
declaration or other act on the part of the Trustee or any Holder.

SECTION 112. OTHER TERMS OF 2020 DEBENTURES.

     Without limiting the foregoing provisions of this Article One, the terms of
the 2020 Debentures shall be as set forth in the form of 2020 Debentures set
forth in Annex A hereto and as provided in the Indenture. In the event of a
conflict or inconsistency between the Indenture and this First Supplement, this
First Supplement will control.

                                  ARTICLE TWO
                           AMENDMENTS TO THE INDENTURE

     The amendments contained herein shall apply to 2020 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 2020
Debentures. These amendments shall be effective for so long as any 2020
Debentures remain Outstanding.

SECTION 201. DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION.

     (a) Section 101 of the Indenture is amended by inserting, amending or
restating, as the case may be, in their appropriate alphabetical position, the
following definitions:

     "Capital Stock" or "capital stock" of any Person means any and all shares,
interests, partnership interests, participations, rights or other equivalents
(however designated) of such Person's equity interest (however designated)
issued by that Person.

     "Change in Control" has the meaning specified in Section 1501(b) of the
Indenture.

     "Change in Control Purchase Date" has the meaning specified in Section
1501(b) of the Indenture.

     "Change in Control Purchase Notice" has the meaning specified in Section
1501(b) of the Indenture.



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     "Change in Control Purchase Price" has the meaning specified in Section
1501(b) of the Indenture.

     "Common Stock" means any stock of any class of the Company 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. However, subject to the
provisions of Section 1412, shares issuable on conversion of Securities shall
include only shares of the class designated as Common Stock of the Company at
the date of this instrument or shares of any class or classes resulting from any
reclassification or reclassifications thereof and which have 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 are
not subject to redemption by the Company; provided that if at any time there
shall be more than one such resulting class, the shares of each such class then
so issuable shall be substantially in the proportion which the total number of
shares of such class resulting from all such reclassifications bears to the
total number of shares of all such classes resulting from all such
reclassifications; provided further, however, that if the Company shall
reclassify its Common Stock by authorizing one or more series of so-called
tracking stock and immediately after such reclassification, the Company shall
have retained at least a majority ownership interest in the business represented
by a series of tracking stock (any such series of tracking stock, a "Subsidiary
Track") and the holders of Common Stock of the Company prior to such
reclassification shall continue to hold the shares of another series of tracking
stock immediately after such reclassification in substantially the same
proportions as they held the Common Stock immediately prior to the
reclassification (the "Public Track"), thereafter the Subsidiary Track (or if
there is more than one, the Subsidiary Tracks) shall not be treated as Common
Stock, and only the Public Track shall be so treated.

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

     "Conversion Agent" means the Person authorized by the Company to effect the
conversion of the 2020 Debentures and shall initially be the agent specified in
Section 101 hereof.

     "Corporate Trust Office" means the principal office of the Trustee at which
at any particular time its corporate trust business shall be administered, which
office at the date of original execution of this Indenture is located at 1 Bank
One Plaza, Suite IL-1-0126, Chicago, Illinois 60670-0126, Attention: Corporate
Trust Services Division, except that, with respect to presentation of the
Securities for payment or registration of transfers or exchanges and the
location of the register, such term means the office or agency of the Trustee at
which at any particular time its corporate agency business shall be conducted,
which at the date of original execution of this Indenture is located at 14 Wall
Street, 8th Floor-Window 2, New York, New York 10005.

     "Notional Conversion Price" means the price of a share of Common Stock
calculated by FIRST, adding (i) the Issue Price to (ii) Original Issue Discount
accrued to the measurement date


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and SECOND, dividing that sum by the quotient obtained by dividing (x) $1,000 by
(y) the then-applicable conversion price under this Indenture.

     "Exchange Act" means the Securities Exchange Act of 1934, as amended, or
any successor statute.

     "Expiration Time" has the meaning specified in Section 1405.

     "Global Securities" has the meaning specified in Section 101 hereof.

     "Holder Repurchase Notice" has the meaning specified in Section 1501(a) of
the Indenture.

     "Interest", when used with respect to an Original Issue Discount Security
which by its terms bears interest only after Maturity or a Tax Event, means
interest payable after Maturity or a Tax Event.

     "Issue Date" of any 2020 Debenture means the date on which the 2020
Debenture was originally issued or deemed issued as set forth on the face of the
2020 Debenture.

     "Issue Price" of any 2020 Debenture means, in connection with the original
issuance of such 2020 Debenture, the initial issue price at which the 2020
Debenture is sold to the public as set forth on the face of the 2020 Debenture.

     "Market Price" has the meaning specified in Section 1504 of the Indenture.

     "Optional Repurchase Price" has the meaning specified in Section 1501(a) of
the Indenture.

     "Original Issue Discount" of any 2020 Debenture means the difference
between the Issue Price and the Principal Amount of the 2020 Debenture as set
forth on the face of the 2020 Debenture.

     "Principal Amount" of a 2020 Debenture means the Principal Amount as set
forth on the face of the 2020 Debenture.

     "Purchased Shares" has the meaning specified in 1405 of the Indenture.

     "Repurchase Date" has the meaning specified in Section 1501 of the
Indenture.

     "Repurchase Notice" means either the Change in Control Purchase Notice or
the Holder Repurchase Notice, as the case may be.

     "Repurchase Price" means either the Change in Control Purchase Price or the
Optional Repurchase Price, as the case may be.



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     "Responsible Officer", when used with respect to the Trustee, means any
officer assigned to administer corporate trust matters and also means, with
respect to a particular corporate trust matter, any other officer to whom such
matter is referred because of his or her knowledge of and familiarity with the
particular subject.

     "Restated Principal Amount" has the meaning specified in Section 1601 of
the Indenture.

     "Sale Price" has the meaning specified in Section 1504 of the Indenture.

     "Securities" has the meaning stated in the first recital of this Indenture
and more particularly means any Securities authenticated and delivered under
this Indenture, including 2020 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 August 7, 2000, 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 August 7, 2000, there is more than an
insubstantial risk that interest (including Original Issue Discount) payable on
the 2020 Debentures (i) would not be deductible on a current accrual basis and
(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.

     "Trading Day" means a day during which trading in securities generally
occurs on the New York Stock Exchange or, if the Common Stock is not listed on
the New York Stock Exchange, on the principal other national or regional
securities exchange on which the Common Stock is then listed or, if the Common
Stock is not listed on a national or regional securities exchange, on the Nasdaq
National Market System or, if the Common Stock is not quoted on the Nasdaq
National Market System, on the principal other market on which the Common Stock
is then traded.

     "2020 Debentures" means the Zero Coupon Convertible Debentures due August
2020 of the Company authorized by resolution of the Board of Directors.

     "Voting Stock" means any class or classes of Capital Stock pursuant to
which the holders thereof under ordinary circumstances have the power to vote in
the election of the board of directors, managers or trustees of any Person (or
other Persons performing similar functions), irrespective of whether or not, at
the time, Capital Stock of any other class or classes shall have, or might have,
voting power by reason of the happening of any contingency.


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(b)  The Indenture shall be amended by replacing Section 112 of the Indenture
     with the following:

     Section 112. GOVERNING LAW.

     THIS INDENTURE AND THE SECURITIES SHALL BE GOVERNED BY AND CONSTRUED IN
     ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO
     CONFLICTS OF LAW PRINCIPLES THEREOF.

SECTION 202. REGISTRATION, REGISTRATION OF TRANSFER AND EXCHANGE.

     The Indenture shall be amended by replacing the seventh paragraph of
Section 305 with the following paragraph:

          The Company shall not be required (i) to issue, register the transfer
     of or exchange the Securities of any series during a period beginning at
     the opening of business 15 days before the day of the mailing of a notice
     of redemption of Securities of that series 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 2020 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 2020 Debenture or portions thereof in respect of which a
     Change in Control Purchase Notice or Holder Repurchase Notice has been
     delivered and not withdrawn by the Holder thereof (except, in the case of
     the purchase of a 2020 Debenture in part, the portion not to be purchased).

SECTION 203. MUTILATED, DESTROYED, LOST AND STOLEN SECURITIES.

     The Indenture shall be amended by replacing the third paragraph of Section
306 with the following paragraph:

          In case any such mutilated, destroyed, lost or stolen Security has or
     is about to become due and payable, or is about to be redeemed or purchased
     by the Company upon a Change in Control or purchased by the Company on a
     Repurchase Date, in each case pursuant to Article Fifteen, the Company in
     its discretion may, instead of issuing a new Security, pay such Security.

SECTION 204. PAYMENT OF INTEREST; INTEREST RIGHTS PRESERVED.

     Section 307 of the Indenture is amended by adding the following paragraph
immediately following Clause (2) thereof:

          In the case of any Security which is converted after any Regular
     Record Date and on or prior to the next succeeding Interest Payment Date
     (other than any Security whose Maturity is prior to such Interest Payment
     Date), interest whose Stated Maturity is on such Interest Payment Date
     shall be payable on such Interest Payment Date


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<PAGE>   13


     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 Security (or one or more Predecessor Securities) is registered at
     the close of business on such Regular Record Date. Except as otherwise
     expressly provided in the immediately preceding sentence, in the case of
     any Security which is converted, interest whose Stated Maturity is after
     the date of conversion of such Security shall not be payable.

SECTION 205. CANCELLATION.

     The first sentence of Section 309 of the Indenture shall be amended by
inserting the word "conversion" in the first sentence thereof, following the
word "redemption".

SECTION 206. EVENTS OF DEFAULT; UNCONDITIONAL RIGHT OF HOLDERS TO RECEIVE
PRINCIPAL, PREMIUM AND INTEREST.

          (a) Clause (1) of Section 501 of the Indenture is amended to read in
     its entirety as follows:

               (1) default in the payment of any interest upon any Security,
          including default in the payment of any interest after the conversion
          of the 2020 Debentures to interest-bearing 2020 Debentures pursuant to
          Section 1601 upon any 2020 Debentures when such interest becomes due
          and payable and continuance of such default for a period of 30 days;

          (b) Clause (2) of Section 501 of the Indenture is amended to read in
     its entirety as follows:

               (2) default in the payment of the Principal Amount at Maturity
          (or, if the 2020 Debentures have been converted to interest-bearing
          2020 Debentures pursuant to Section 1601, the Restated Principal
          Amount), the Redemption Price, the Optional Repurchase Price or the
          Change in Control Purchase Price when the same becomes due and payable
          upon redemption, upon declaration of acceleration, when due for
          repurchase by the Company or otherwise;

     (c) Section 508 of the Indenture shall be amended by replacing that section
with the following:

     Section 508. UNCONDITIONAL RIGHT OF HOLDERS TO RECEIVE PRINCIPAL, PREMIUM
AND, INTEREST.

          Notwithstanding any other provision in this Indenture, the Holder of
     any Security shall have the right, which is absolute and unconditional, to
     receive payment of the principal of (and premium, if any) and (subject to
     Section 307) interest on, if any, with respect to such Security on the
     Maturity or Maturities 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 Optional Repurchase Price on the
     Repurchase Date,


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<PAGE>   14

     or in the case of a Change in Control, to receive the Change in Control
     Purchase Price on the Change in Control Purchase Date) and to institute
     suit for the enforcement of any such payment on or after such respective
     dates, and such rights shall not be impaired without the consent of such
     Holder.

SECTION 207. THE TRUSTEE.

     Article Six of the Indenture shall be amended

          (a) by inserting at the end of Section 607 thereof the following
     paragraph:

          The provisions of this Section 607 shall survive the resignation or
     removal of the Trustee and the termination of this Indenture.

          (b) by deleting the first sentence of Section 609 thereof and
     restating it in its entirety as follows:

               There shall at all times be a Trustee hereunder which shall be a
          Person that is eligible pursuant to the Trust Indenture Act to act as
          such and has a combined capital and surplus of at least $50,000,000
          and an office (which may be an agency office) in the Borough of
          Manhattan, The City of New York.

          (c) by deleting the fourth paragraph of Section 614 thereof and
     replacing it in its entirety with the following:

               The Company agrees to pay to each Authenticating Agent from time
          to time reasonable compensation for its services under this Section
          614.

SECTION 208. CONSOLIDATION.

     Section 801 of the Indenture shall be amended by deleting Clause (c)
thereof and renumbering Clause (d) as Clause (c).

SECTION 209. SUPPLEMENTAL INDENTURES.

     Section 902 of the Indenture shall be amended by inserting at the end of
the first numbered clause to the provision in the first paragraph the phrase "or
adversely affect the right to convert any Security as contemplated by Article
Fourteen."



SECTION 210. EXECUTION OF SUPPLEMENTAL INDENTURES

     Article Nine of the Indenture shall be amended by deleting Section 903
     thereof and replacing it with the following:


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<PAGE>   15

          Section 903. EXECUTION OF SUPPLEMENTAL INDENTURES.

          In executing, or accepting the additional trusts created by, any
     supplemental indenture permitted by this Article or the modifications
     thereby of the trusts created by this Indenture, the Trustee shall be
     entitled to receive, and (subject to Section 601) shall be fully protected
     in relying upon, an Opinion of Counsel and an Officer's Certificate stating
     that the execution of such supplemental indenture is authorized or
     permitted by this Indenture. The Trustee may, but shall not be obligated
     to, enter into any such supplemental indenture which affects the Trustee's
     own rights, duties or immunities under this Indenture or otherwise.

SECTION 211. MAINTENANCE OF OFFICE OR AGENCY.

     The first paragraph of Section 1002 of the Indenture shall be amended by
deleting the first sentence thereof and replacing it with the following:

          The Company will maintain in each Place of Payment for any series of
     Securities an office or agency where Securities of that series may be
     presented or surrendered for payment, where Securities of that series may
     be surrendered for registration of transfer or exchange, where 2020
     Debentures may be surrendered for conversion and where notices and demands
     to or upon the Company in respect of the Securities of that series and this
     Indenture may be served. The Company will give prompt written notice to the
     Trustee of the location, and any change in the location, of such office or
     agency. If at any time the Company shall fail to maintain any such required
     office or agency or shall fail to furnish the Trustee with the address
     thereof, such presentations, surrenders, notices and demands may be made or
     served at the Corporate Trust Office of the Trustee, and the Company hereby
     appoints the Trustee as its agent to receive all such presentations,
     surrenders, notices and demands.

SECTION 212. COVENANTS.

          Article Ten of the Indenture shall be amended by deleting therefrom
     Sections 1006, 1007 and 1008 in their entirety, together with all
     references throughout the Indenture to such sections and inserting in place
     of the text of each such section the word "Reserved."

SECTION 213. REDEMPTION.

     Article Eleven of the Indenture shall be amended by

          (a) Inserting at the end of Clause (6) of Section 1104, "and " and
     inserting a new Clause (7), "(7) that there exists a conversion privilege,
     if applicable.", and

          (b) inserting the following section in its entirety:


                                       12
<PAGE>   16

Section 1108. CONVERSION ARRANGEMENT ON CALL FOR REDEMPTION

          In connection with 2020 Debentures, the Company may arrange for the
     purchase and conversion of any 2020 Debentures called for redemption by an
     agreement with one or more investment bankers or other purchasers to
     purchase such 2020 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 2020 Debentures, is not less than the Redemption
     Price of such 2020 Debentures. Notwithstanding anything to the contrary
     contained in this Article Eleven, the obligation of the Company to pay the
     Redemption Price of such 2020 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 2020 Debentures called for redemption. If such an agreement is
     entered into, any 2020 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 Fourteen) 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 2020 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 2020 Debentures.
     Without the Paying Agent's prior written consent, no arrangement between
     the Company and such purchasers for the purchase and conversion of any 2020
     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 2020 Debentures between the Company and such purchasers, including 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 214. COUNTERPARTS.

     Article Thirteen of the Indenture is modified by deleting therefrom in its
entirety Section 1306 and adding the text thereof to an unnumbered paragraph
prior to the signature page.

SECTION 215. CONVERSION.


                                       13

<PAGE>   17

       The Indenture is amended by adding the following Article Fourteen:

                                ARTICLE FOURTEEN

                            CONVERSION OF SECURITIES

Section 1401. APPLICABILITY OF ARTICLE.

     Pursuant to Section 301, provision is hereby made for the conversion of the
2020 Debentures pursuant to this Article Fourteen.

Section 1402. UCONVERSION PRIVILEGE AND CONVERSION PRICE.

     Subject to and upon compliance with the provisions of this Article, at the
option of the Holder thereof, any Security or any portion of the principal
amount at which is $1,000 or an integral multiple of $1,000 at Stated Maturity
thereof may be converted based on the principal amount at Stated Maturity
thereof, or of such portion thereof, into fully paid and nonassessable shares
(calculated as to each conversion to the nearest 1/100 of a share) of Common
Stock of the Company, at the conversion price, determined as hereinafter
provided, in effect at the time of conversion. The ratio derived by dividing
$1,000 by the then-applicable conversion price is referred to herein as the
"conversion rate." Such conversion right shall commence on the date of issuance
of the Securities and expire at the close of business on the date provided for
in the Securities with respect to such Securities. In case a Security or portion
thereof is called for redemption, such conversion right in respect of the
Security or portion so called shall expire at the close of business on the
Business Day prior to the Redemption Date, unless the Company defaults in making
the payment due upon redemption.

The price at which shares of Common Stock shall be delivered upon conversion is
herein referred to as the "conversion price". The initial conversion price shall
be fixed in the Security. The conversion price shall be adjusted in certain
instances as provided in Section 1405.

Section 1403. EXERCISE OF CONVERSION PRIVILEGE.

     In order to exercise the conversion privilege, the Holder of any Security
to be converted shall surrender such Security, duly endorsed or assigned to the
Company or in blank, at any office or agency of the Company maintained for that
purpose pursuant to Section 1002, accompanied by written notice to the Company
at such office or agency that the Holder elects to convert such Security or, if
less than the entire principal amount thereof is to be converted, the portion
thereof to be converted. On conversion of a 2020 Debenture, that portion of
accrued Original Issue Discount (and interest, if the Company has exercised its
option provided for in Section 1601) 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 1601, the later of (x) the date of such exercise and (y)
the date on which interest was last paid) of the 2020 Debenture through the
conversion date with respect to


                                       14
<PAGE>   18

the converted 2020 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 2020 Debenture being converted pursuant
to the provisions hereof; and the fair market value of such 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 interest, if the Company as exercised its option provided for in
Section 1601) 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 of the 2020 Debenture being
converted pursuant to the provisions hereof. In the event that the Company has
exercised its option under Section 1601, then any securities surrendered for
conversion during the period from the close of business on any Regular Record
Date next preceding any Interest Payment Date to the opening of business on such
Interest Payment Date shall (except in the case of Securities or portions
thereof which have been called for redemption on a Redemption Date within such
period) be accompanied by payment in immediately available 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 Securities being surrendered
for conversion. Except as provided in the preceding two sentences and subject to
the third paragraph of Section 307, no payment or adjustment shall be made upon
any conversion on account of any Original Issue Discount (and interest, if the
Company has exercised its option provided for in Section 1601) accrued on the
2020 Debentures surrendered for conversion or on account of any dividends on the
Common Stock issued upon conversion.

     Securities shall be deemed to have been converted immediately prior to the
close of business on the day of surrender of such Securities for conversion in
accordance with the foregoing provisions, and at such time the rights of the
Holders of such Securities as Holders shall cease, and the Person or Persons
entitled to receive the Common Stock issuable upon conversion shall be treated
for all purposes as the record holder or holders of such Common Stock at such
time. As promptly as practicable on or after the conversion date, the Company
shall issue and shall deliver at such office or agency a certificate or
certificates for the number of full shares of Common Stock issuable upon
conversion, together with payment in lieu of any fraction of a share, as
provided in Section 1404.

     In the case of any Security which is converted in part only, upon such
conversion the Company shall execute and the Trustee shall authenticate and
deliver to the Holder thereof, at the expense of the Company, a new Security or
Securities of authorized denominations in aggregate principal amount equal to
the unconverted portion of the principal amount of such Security.

Section 1404. FRACTIONS OF SHARES.

     No fractional shares of Common Stock shall be issued upon conversion of
Securities. If more than one Security shall be surrendered for conversion at one
time by

                                       15

<PAGE>   19

the same Holder, the number of full shares which shall be issuable upon
conversion thereof shall be computed on the basis of the aggregate principal
amount of the Securities (or specified portions thereof) so surrendered. Instead
of any fractional share of Common Stock which would otherwise be issuable upon
conversion of any Security or Securities (or specified portions thereof), the
Company shall pay a cash adjustment in respect of such fraction in an amount
equal to the same fraction of the market price per share of Common Stock (as
determined by the Board of Directors or in any manner prescribed by the Board of
Directors) at the close of business on the day of conversion.

Section 1405. ADJUSTMENT OF CONVERSION PRICE.

          (1) In case at any time after the date of the issuance of the
     applicable Securities, the Company shall pay or make a dividend or other
     distribution on any class of capital stock of the Company in Common Stock,
     the conversion price in effect at the opening of business on the day
     following the date fixed for the determination of stockholders entitled to
     receive such dividend or other distribution shall be reduced by multiplying
     such conversion price by a fraction of which the numerator shall be the
     number of shares of Common Stock outstanding at the close of business on
     the date fixed for such determination and the denominator shall be the sum
     of such number of shares and the total number of shares constituting such
     dividend or other distribution, such reduction to become effective
     immediately after the opening of business on the day following the date
     fixed for such determination. For the purposes of this paragraph (1), the
     number of shares of Common Stock at any time outstanding shall not include
     shares held in the treasury of the Company but shall include shares
     issuable in respect of scrip certificates issued in lieu of fractions of
     shares of Common Stock. The Company will not pay any dividend or make any
     distribution on shares of Common Stock held in the treasury of the Company.

          (2) In case at any time after the date of the issuance of the
     applicable Securities, the Company shall issue rights or warrants to all
     holders of its Common Stock (not being available on an equivalent basis to
     Holders of the Securities upon conversion) entitling them to subscribe for
     or purchase shares of Common Stock at a price per share less than the
     current market price per share (determined as provided in paragraph (8) of
     this Section) of the Common Stock on the date fixed for the determination
     of stockholders entitled to receive such rights, options or warrants (other
     than pursuant to a dividend reinvestment plan), the conversion price in
     effect at the opening of business on the day following the date fixed for
     such determination shall be reduced by multiplying such conversion price by
     a fraction of which the numerator shall be the number of shares of Common
     Stock outstanding at the close of business on the date fixed for such
     determination plus the number of shares of Common Stock which the aggregate
     of the offering price of the total number of shares of Common Stock so
     offered for subscription or purchase would purchase at such current market
     price and the denominator shall be the number of shares of Common Stock
     outstanding at the close of business on the date fixed for such
     determination plus the number of shares of Common Stock so offered for
     subscription or purchase, such reduction to become effective immediately
     after the opening of


                                       16
<PAGE>   20

     business on the day following the date fixed for such determination. For
     the purposes of this paragraph (2), the number of shares of Common Stock at
     any time outstanding shall not include shares held in the treasury of the
     Company but shall include shares issuable in respect of scrip certificates
     issued in lieu of fractions of shares of Common Stock. The Company will not
     issue any rights or warrants in respect of shares of Common Stock held in
     the treasury of the Company.

          (3) In case at any time after the date of the issuance of the
     applicable Securities, outstanding shares of Common Stock shall be
     subdivided into a greater number of shares of Common Stock, the conversion
     price in effect at the opening of business on the day following the day
     upon which such subdivision becomes effective shall be proportionately
     reduced, and, conversely, in case outstanding shares of Common Stock shall
     each be combined into a smaller number of shares of Common Stock, the
     conversion price in effect at the opening of business on the day following
     the day upon which such combination becomes effective shall be
     proportionately increased, such reduction or increase, as the case may be,
     to become effective immediately after the opening of business on the day
     following the day upon which such subdivision or combination becomes
     effective.

          (4) In case at any time after the date of the issuance of the
     applicable Securities, the Company shall, by dividend or otherwise,
     distribute to all holders of its Common Stock evidences of its indebtedness
     or assets (including securities, but excluding any rights or warrants
     referred to in paragraph (2) of this Section, any dividend or distribution
     paid in cash out of the retained earnings of the Company and any dividend
     or distribution referred to in paragraph (1) of this Section), the
     conversion price shall be adjusted so that the same shall equal the price
     determined by multiplying the conversion price in effect immediately prior
     to the close of business on the date fixed for the determination of
     stockholders entitled to receive such distribution by a fraction of which
     the numerator shall be the current market price per share (determined as
     provided in paragraph (8) of this Section) of the Common Stock on the date
     fixed for such determination less the then fair market value (as determined
     by the Board of Directors, whose determination shall be conclusive and
     described in a Board Resolution filed with the Trustee) of the portion of
     the assets or evidences of indebtedness so distributed applicable to one
     share of Common Stock and the denominator shall be such current market
     price per share of the Common Stock, such adjustment to become effective
     immediately prior to the opening of business on the day following the date
     fixed for the determination of stockholders entitled to receive such
     distribution.

          (5) In case at any time after the date of the issuance of the
     applicable Securities, the Company shall, by dividend or otherwise,
     distribute to all holders of its Common Stock cash (excluding any cash that
     is distributed upon a merger or consolidation to which Section 1412 applies
     or as part of a distribution referred to in paragraph (4) of this Section)
     in an aggregate amount that, combined together with:


                                       17

<PAGE>   21


     (A)  the aggregate amount of any other such all-cash distributions made to
          all holders of its Common Stock within the 12 months preceding the
          date of payment of such distribution and in respect of which no
          adjustment pursuant to this paragraph (5) has been made, and

     (B)  the aggregate of any cash plus the fair market value (as determined by
          the Board of Directors, whose determination shall be conclusive and
          described in a Board Resolution) of consideration payable in respect
          of any tender offer by the Company or any of its subsidiaries for all
          or any portion of the Common Stock concluded within the 12 months
          preceding the date of payment of such distribution and in respect of
          which no adjustment pursuant to paragraph (6) of this Section has been
          made,

(the amount of such cash distribution together with the amounts described in
clauses (A) and (B) above being referred to herein as the "Aggregate Cash
Distribution Amount") exceeds 10% of the product of (I) the current market price
per share of the Common Stock on the date for the determination of holders of
shares of Common Stock entitled to receive such distribution, times (II) the
number of shares of Common Stock outstanding on such date (the amount by which
the Aggregate Cash Distribution Amount exceeds 10% of the product of the amounts
described in clauses (I) and (II) above being referred to herein as the "Excess
Amount"), then, and in each such case, immediately after the close of business
on such date for determination, the conversion price shall be decreased in
accordance with the following formula:

                      M - (EA/O)
     AC = CP x        ---------
                         M

Where:

     AC = the adjusted conversion price.

     CP = the conversion price in effect immediately prior to
          the close of business on the date fixed for
          determination of the stockholders entitled to receive
          the distribution.

      M = the current market price per share (determined as
          provided in paragraph (8) of this Section) of the
          Common Stock on the date fixed for determination of
          the stockholders entitled to receive the
          distribution.

     EA = the Excess Amount.

      O = the number of shares of Common Stock outstanding on
          the date fixed for determination of the stockholders
          entitled to receive the distribution.


                                       18

<PAGE>   22


          (6) In case at any time after the date of the issuance of the
     applicable Securities, a tender offer made by the Company or any Subsidiary
     for all or any portion of the Common Stock shall expire and such tender
     offer (as amended upon the expiration thereof) shall require the payment to
     stockholders (based on the acceptance (up to any maximum specified in the
     terms of the tender offer) of Purchased Shares (as defined below)) of an
     aggregate consideration having a fair market value (as determined by the
     Board of Directors, whose determination shall be conclusive and described
     in a Board Resolution) that combined together with:

          (A)  the aggregate of the cash plus the fair market value (as
               determined by the Board of Directors, whose determination shall
               be conclusive and described in a Board Resolution), as of the
               expiration of such tender offer, of consideration payable in
               respect of any other tender offer, by the Company or any
               Subsidiary for all or any portion of the Common Stock expiring
               within the 12 months preceding the expiration of such tender
               offer and in respect of which no adjustment pursuant to this
               paragraph (6) has been made, and

          (B)  the aggregate amount of any all-cash distributions referred to in
               paragraph (5) of this Section 1405 made to all holders of the
               Company's Common Stock within 12 months preceding the expiration
               of such tender offer and in respect of which no adjustment
               pursuant to paragraph (5) of this Section has been made,

     exceeds 10% of the product of (I) the current market price per share of the
     Common Stock (determined as provided in paragraph (8) of this Section) as
     of the last time (the "Expiration Time") tenders could have been made
     pursuant to such tender offer (as it may be amended), times (II) the number
     of shares of Common Stock outstanding (including any tendered shares) on
     the Expiration Time, then, and in each such case, immediately prior to the
     opening of business on the day after the date of the Expiration Time, the
     conversion price shall be adjusted in accordance with the following
     formula:

                  (M x O) - C
       AC = CP x  -----------
                  M x (O - TS)

Where:

       AC = the adjusted conversion price.

       CP = the conversion price immediately prior to close of
           business on the date of the Expiration Time.


                                       19

<PAGE>   23

       M = the current market price per share of the Common
           Stock (determined as provided in paragraph (8) of
           this Section) on the date of the Expiration Time.

       O = the number of shares of Common Stock outstanding (including any
           tendered shares) on the Expiration Time.

       C = the amount of cash plus the fair market value (as
           determined by the Board of Directors, whose
           determination shall be conclusive and described in a
           Board Resolution) of the aggregate consideration
           payable to stockholders based on the acceptance (up
           to any maximum specified in the terms of the tender
           offer) of Purchased Shares (as defined below).

      TS = the number 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").

          (7) The reclassification of Common Stock into securities other than
     Common Stock (other than (i) any reclassification upon a consolidation or
     merger to which Section 1412 applies or (ii) any reclassification to create
     a Subsidiary Track) shall be deemed to involve (a) a distribution of such
     securities to all holders of Common Stock (and the effective date of such
     reclassification shall be deemed to be "the date fixed for the
     determination of stockholders entitled to receive such distribution" and
     "the date fixed for such determination" within the meaning of paragraph (4)
     of this Section), and (b) a subdivision or combination, as the case may be,
     of the number of shares of Common Stock outstanding immediately prior to
     such reclassification into the number of shares of Common Stock outstanding
     immediately thereafter (and the effective date of such reclassification
     shall be deemed to be "the day upon which such subdivision becomes
     effective" or "the day upon which such combination becomes effective", as
     the case may be, and "the day upon which such subdivision or combination
     becomes effective" within the meaning of paragraph (3) of this Section).

          (8) For the purpose of any computation under paragraphs (2), (4), (5)
     and (6) of this Section, 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 five consecutive Trading Days selected by the Company commencing
     not more than 20 Trading Days before, and ending not later than the earlier
     of the day in question and the day before the "ex" date with request to the
     issuance or distribution requiring such computation. 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 day, the average of the reported
     closing bid and asked prices regular way, in either case on the New York
     Stock Exchange or, if the Common Stock is not listed or admitted to trading
     on such Exchange, 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, on the Nasdaq
     National Market or, if the Common Stock is not listed or admitted to
     trading on any national securities exchange or quoted on the Nasdaq


                                       20

<PAGE>   24

     National Market, the average of the closing bid and asked prices in the
     over-the-counter market as furnished by any New York Stock Exchange member
     firm selected from time to time by the Company for that purpose. For
     purposes of this paragraph, the term "'ex' date", when used with respect to
     any issuance or distribution, means the first date on which the Common
     Stock trades regular way on such exchange or in such market without the
     right to receive such issuance or distribution.

          (9) No adjustment in the conversion price shall be required unless
     such adjustment (plus any adjustments not previously made by reason of this
     paragraph (9)) would require an increase or decrease of at least 1% in such
     price; provided, however, that any adjustments which by reason of this
     paragraph (9) are not required to be made shall be carried forward and
     taken into account in any subsequent adjustment. All calculations under
     this paragraph (9) shall be made to the nearest cent.

          (10) The Company may make such reductions in the conversion price, in
     addition to those required by this Section, as it considers to be advisable
     in order to avoid or diminish any income tax to any holders of shares of
     Common Stock resulting from any dividend or distribution of stock or
     issuance of rights or warrants to purchase or subscribe for stock or from
     any event treated as such for income tax purposes or for any other reasons.
     The Company shall have the power to resolve any ambiguity or correct any
     error in this paragraph (10) and its actions in so doing shall be final and
     conclusive.

Section 1406. NOTICE OF ADJUSTMENTS OF CONVERSION PRICE.


          Whenever the conversion price is adjusted as herein provided:

          (a) the Company shall compute the adjusted conversion price in
     accordance with Section 1405 and shall prepare an Officers' Certificate,
     one of the signatories of which shall be the Treasurer of the Company,
     setting forth the adjusted conversion price and the adjusted conversion
     rate and showing in reasonable detail the facts upon which such adjustment
     is based, and such certificate shall forthwith be filed at each office or
     agency maintained for the purpose of conversion of Securities pursuant to
     Section 1002; and

          (b) a notice stating that the conversion price has been adjusted and
     setting forth the adjusted conversion price shall forthwith be required,
     and as soon as practicable after it is required, such notice shall be
     mailed by the Company to all Holders at their last addresses as they shall
     appear in the Security Register.

Section 1407. NOTICE OF CERTAIN CORPORATE ACTION.

     In case at any time after the date 20 days prior to the date on which the
Securities first become convertible:


                                       21
<PAGE>   25


          (a) the Company shall declare a dividend (or any other distribution)
     on its Common Stock payable otherwise than in cash out of its retained
     earnings; or

          (b) the Company shall authorize the granting to the holders of its
     Common Stock of rights or warrants to subscribe for or purchase any shares
     of capital stock of any class or of any other rights; or

          (c) the Company shall effect any reclassification of the Common Stock
     of the Company (other than a subdivision or combination of its outstanding
     shares of Common Stock), or of any consolidation or merger to which the
     Company is a party and for which approval of any stockholders of the
     Company is required, or of the sale or transfer of all or substantially all
     of the assets of the Company; or

          (d) the occurrence of the voluntary or involuntary dissolution,
     liquidation or winding up of the Company;

then the Company shall cause to be filed at each office or agency maintained for
the purpose of conversion of Securities pursuant to Section 1002, and shall
cause to be mailed to all Holders at their last addresses as they shall appear
in the Security Register, at least 20 days (or 10 days in any case specified in
clause (a) or (b) above) prior to the applicable record or effective date
hereinafter specified, a notice stating (x) the date on which a record is to be
taken for the purpose of such dividend, distribution, rights or warrants, or, if
a record is not to be taken, the date as of which the holders of Common Stock of
record to be entitled to such dividend, distribution, rights or warrants are to
be determined, or (y) the date on which such reclassification, consolidation,
merger, share exchange, sale, transfer, dissolution, liquidation or winding up
is expected to become effective, and the date as of which it is expected that
holders of Common Stock of record shall be entitled to exchange their shares of
Common Stock for securities, cash or other property deliverable upon such
reclassification, consolidation, merger, share exchange, sale, transfer,
dissolution, liquidation or winding up. Neither the failure to give such notice
nor any defect therein shall affect the legality or validity of the proceedings
described in clauses (a) through (d) of this Section 1407. If at the time the
Trustee shall not be the Conversion Agent, a copy of such notice shall also
forthwith be filed by the Company with the Trustee.

Section 1408. COMPANY TO RESERVE COMMON STOCK.

     The Company shall at all times reserve and keep available, free from
preemptive rights, out of its authorized but unissued Common Stock, for the
purpose of effecting the conversion of Securities, the full number of shares of
Common Stock then issuable upon the conversion of all outstanding Securities.

Section 1409. TAXES ON CONVERSIONS.

     The Company will pay any and all taxes that may be payable in respect of
the issue or delivery of shares of Common Stock on conversion of Securities
pursuant hereto.


                                       22

<PAGE>   26


The Company shall not, however, be required to pay any tax which may be payable
in respect of any transfer involved in the issue and delivery of shares of
Common Stock in a name other than that of the Holder of the Security or
Securities to be converted, and no such issue or delivery shall be made unless
and until the Person requesting such issue has paid to the Company the amount of
any such tax, or has established to the satisfaction of the Company that such
tax has been paid.

Section 1410. COVENANT AS TO COMMON STOCK.

     The Company covenants that all shares of Common Stock which may be issued
upon conversion of Securities will upon issue be fully paid and nonassessable
and, except as provided in Section 1409, the Company will pay all taxes, liens
and charges with respect to the issue thereof.

Section 1411. CANCELLATION OF CONVERTED SECURITIES.

     All Securities delivered for conversion shall be delivered to the Trustee
to be cancelled by or at the direction of the Trustee, which shall dispose of
the same as provided in Section 309.

Section 1412. PROVISIONS IN CASE OF CONSOLIDATION, MERGER OR SALE OF ASSETS.

     In case of any consolidation of the Company with, or merger of the Company
into, any other Person, any merger of another Person into the Company (other
than a merger which does not result in any reclassification, conversion,
exchange or cancellation of outstanding shares of Common Stock of the Company)
or any sale or transfer of all or substantially all of the assets of the
Company, the Person formed by such consolidation or resulting from such merger
or which acquires such assets, as the case may be, shall execute and deliver to
the Trustee a supplemental indenture providing that the Holder of each Security
then outstanding shall have the right thereafter, during the period such
Security shall be convertible as specified in Section 1402, to convert such
Security only into the kind and amount of securities, cash and other property
receivable upon such consolidation, merger, sale or transfer by a holder of the
number of shares of Common Stock of the Company into which such Security might
have been converted immediately prior to such consolidation, merger, sale or
transfer, assuming such holder of Common Stock of the Company (i) is not a
Person with which the Company consolidated or into which the Company merged or
which merged into the Company or to which such sale or transfer was made, as the
case may be ("constituent Person"), or an Affiliate of a constituent Person and
(ii) failed to exercise his rights of election, if any, as to the kind or amount
of securities, cash and other property receivable upon such consolidation,
merger, sale or transfer (provided that if the kind or amount of securities,
cash and other property receivable upon such consolidation, merger, sale or
transfer is not the same for each share of Common Stock of the Company held
immediately prior to such consolidation, merger, sale or transfer by other than
a constituent Person or an Affiliate thereof and in respect of which such rights
of election shall not have been exercised ("non-electing share"), then for the
purpose of this Section the kind and amount of securities, cash and other
property


                                       23

<PAGE>   27

receivable upon such consolidation, merger, sale or transfer 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), and assuming, if such
consolidation, merger, sale or transfer is prior to the date upon which the
Securities first become convertible, that the Securities were convertible at the
time of such consolidation, merger, sale or transfer at the initial conversion
price specified in Section 1402 as adjusted from the date of the issuance of the
applicable Securities to such time pursuant to Section 1405. Such supplemental
indenture shall provide for adjustments which, for events subsequent to the
effective date of such supplemental indenture, shall be as nearly equivalent as
may be practicable to the adjustments provided for in this Article. The above
provisions of this Section shall similarly apply to successive consolidations,
mergers, sales or transfers.

Section 1413. VOLUNTARY DECREASE IN CONVERSION PRICE.

     The Board of Directors of the Company may, from time to time, reduce the
conversion price by any amount for any period of time if (i) the period is at
least 20 days or such longer period as may be required by law (ii) at least 15
days notice is given to the Holders, and (iii) the increase is irrevocable
during the period. The Board of Directors' determination to effect such a
decrease shall be conclusive.

SECTION 216. REPURCHASE AT OPTION OF HOLDER; REPURCHASE UPON CHANGE IN CONTROL;
TAX EVENTS.

   The Indenture is amended by inserting the following new Articles 15 and 16:

                                 ARTICLE FIFTEEN

                REPURCHASE OF SECURITIES AT OPTION OF HOLDER AND
                  AT OPTION OF HOLDER UPON A CHANGE OF CONTROL

Section 1501. GENERAL.

     The Company may be required to repurchase 2020 Debentures in accordance
with their terms and in accordance with this Article.

(a) REPURCHASE AT OPTION OF HOLDER

     2020 Debentures shall be purchased by the Company under the paragraph
"Repurchase by the Company at the Option of the Holder" of the 2020 Debentures
on August 7, 2003 and August 7, 2010 (each, a "Repurchase Date"), at the
repurchase price specified therein (each, a "Optional 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 "Holder Repurchase Notice") at any time from the opening of business
on the date that

                                       24


<PAGE>   28

is 20 Business Days prior to a Repurchase Date until the close of business on
the last Business Day prior to such Repurchase Date stating:

          (A) the certificate number of the 2020 Debenture which the Holder will
     deliver to be repurchased,

          (B) the portion of the Principal Amount of the 2020 Debenture which
     the Holder will deliver to be repurchased, which portion must be $1,000 or
     an integral multiple thereof,

          (C) that such 2020 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" of the 2020
     Debentures and in this Indenture,

          (D) in the event that the Company elects, pursuant to Section 1502
     hereof, to pay the Optional Repurchase Price to be paid as of such
     Repurchase Date, in whole or in part, in Common Stock but such portion of
     the Optional Repurchase Price shall ultimately be payable to such Holder
     entirely in cash because any of the conditions to payment of the Optional
     Repurchase Price in Common Stock is not satisfied prior to the close of
     business on such Repurchase Date, as set forth in Section 1504 hereof,
     whether such Holder elects (i) to withdraw such Holder Repurchase Notice as
     to some or all of the 2020 Debentures to which such Holder Repurchase
     Notice relates (stating the Principal Amount and certificate numbers of the
     2020 Debentures as to which such withdrawal shall relate), or (ii) to
     receive cash in respect of the entire Optional Repurchase Price for all
     2020 Debentures (or portions thereof) to which such Optional Repurchase
     Price relates, and

     (2) delivery of such 2020 Debenture 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 Optional Repurchase Price therefor; provided, however, that such
Optional Repurchase Price shall be so paid pursuant to this Article Fifteen only
if the 2020 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 Repurchase Notice or 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(a)(1), such Holder shall be deemed to have
elected to receive cash in respect of the Optional Repurchase Price for all 2020
Debentures subject to the Holder 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 2020 Debenture only if the Principal Amount of
such portion is


                                       25

<PAGE>   29

$1,000 or an integral multiple of $1,000. Provisions of this Indenture that
apply to the purchase of all of a 2020 Debenture also apply to the purchase of
such portion of such 2020 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 Security to the Paying Agent.

     Notwithstanding anything herein to the contrary, any Holder delivering to
the Paying Agent the Holder Repurchase Notice contemplated by this Section 1501
shall have the right to withdraw such Holder Repurchase Notice at any time prior
to the close of business on 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 Holder Repurchase Notice or written notice of withdrawal thereof.

     Anything herein to the contrary notwithstanding, in the case of Global
Securities, any Repurchase Notice may be delivered or withdrawn and such 2020
Debentures may be surrendered or delivered for purchase in accordance with the
applicable procedures of the Depositary as in effect from time to time.

(b) PURCHASE OF SECURITIES UPON CHANGE IN CONTROL

     (1) If at any time that 2020 Debentures remain Outstanding there shall
occur a Change in Control, 2020 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 1601 has been exercised, the Restated Principal Amount plus accrued and
unpaid interest from the Option Exercise Date 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 subsection (3) of this
Section 1501(b).

     A "Change in Control" shall be deemed to have occurred at the time, after
the original issuance of the Securities, of:

          (A) the acquisition by any person or group of beneficial ownership,
     directly or indirectly, through a purchase, merger or other acquisition
     transaction or series of transactions, of shares of capital stock of the
     Company entitling such person to exercise 50% or more of the total voting
     power of all shares of capital stock of the Company entitled to vote
     generally in the elections of directors (any shares of voting stock of
     which such person or group is the beneficial owner that are not then
     outstanding being deemed outstanding for purposes of calculating

                                       26
<PAGE>   30

     such percentage), other than any such acquisition by the Company, any
     Subsidiary of the Company or any employee benefit plan of the Company
     existing on the date of this Indenture; or

          (B) any consolidation or merger of the Company with or into any other
     person, or any merger of another person with or into the Company, or any
     conveyance, transfer, sale, lease or similar disposition of all or
     substantially all of the Company's assets to another person (other than any
     such transaction (x) that does not result in any reclassification,
     conversion, exchange or cancellation of outstanding shares of Common Stock,
     (y) pursuant to which holders of Common Stock immediately prior to such
     transaction have the entitlement to exercise, directly or indirectly, 50%
     or more of the total voting power of all shares of capital stock entitled
     to vote generally in the election of directors of the continuing or
     surviving person immediately after such transaction or (z) that is effected
     solely to change the jurisdiction of incorporation of the Company and
     results in a reclassification, conversion or exchange of outstanding shares
     of Common Stock into solely shares of common stock);

     PROVIDED, however that a Change in Control shall not be deemed to have
occurred if:

          (X) the Sale Price on any five Trading Days within the period of 10
     consecutive Trading Days ending immediately after the later of the date of
     the Change in Control or the date of the public announcement of the Change
     in Control (in the case of a Change in Control under clause (A) above) or
     the period of 10 consecutive Trading Days ending immediately prior to the
     date of the Change in Control (in the case of a Change in Control under
     clause (B) above) shall equal or exceed 105% of the Notional Conversion
     Price of the Securities in effect on each such Trading Day; or

          (Y) all of the consideration, excluding cash payments for fractional
     shares and cash payments made pursuant to dissenters' appraisal rights, in
     a merger or consolidation otherwise constituting a Change in Control
     consists of shares of Common Stock traded on a national securities exchange
     or quoted on the Nasdaq National Market, or will be so traded or quoted
     immediately following such merger or consolidation, and as a result of such
     merger or consolidation the Securities become convertible solely into such
     common stock.

     For the purpose of the definition of "Change in Control", (i) "person" and
"group" have the meanings given such terms under Section 13(d) and 14(d) of the
Exchange Act or any successor provision to either of the foregoing, and the term
"group" includes any group acting for the purpose of acquiring, holding or
disposing of securities within the meaning of Rule 3d-5(b)(1) under the Exchange
Act (or any successor provision thereto), (ii) a "beneficial owner" shall be
determined in accordance with Rule 13d-3 under the Exchange Act, as in effect on
August 7, 2000, except that the number of shares of Voting Stock of the Company
shall be deemed to include, in addition to all outstanding shares of


                                       27
<PAGE>   31

Voting Stock of the Company and Unissued Shares deemed to be held by the
"person" or "group" (as such terms are defined above) or other person with
respect to which the Change in Control determination is being made, all Unissued
Shares deemed to be held by all other persons, and (iii) the terms "beneficially
owned" and "beneficially own" shall have meanings correlative to that of
"beneficial owner". The term "Unissued Shares" means shares of Voting Stock not
outstanding that are subject to options, warrants, rights to purchase or
conversion privileges exercisable within 60 days of the date of determination of
a Change in Control.

     (2) 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, which shall include the
information required pursuant to Section 1501(b)(3), and shall state:

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

          (B) the date by which the Change in Control Purchase Notice pursuant
     to this Section 1501 must be given;

          (C) the Change in Control Purchase Date;

          (D) the Change in Control Purchase Price;

          (E) briefly, the conversion rights of the 2020 Debentures;

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

          (G) the conversion price and any adjustments thereto;

          (H) that 2020 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;

          (I) the procedures that the Holder must follow to exercise rights
     under this Section 1501;

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

          (K) that the Holder must satisfy the requirements set forth in the
     2020 Debentures in order to convert the Securities.


                                       28
<PAGE>   32

     If any of the 2020 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.

     (3) A Holder may exercise its rights specified in subsection (1) of this
Section 1501(b) upon delivery of a written notice 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 stating:

          (A) the certificate number of the 2020 Debenture which the Holder will
     deliver to be repurchased,

          (B) the portion of the Principal Amount of the 2020 Debenture which
     the Holder will deliver to be repurchased, which portion must be $1,000 or
     an integral multiple thereof,

          (C) that such 2020 Debenture shall be purchased as of the Change in
     Control Date pursuant to the terms and conditions specified under the
     paragraph "Purchase of Securities at the Option of the Holder Upon a Change
     in Control" of the 2020 Debentures and in this Indenture,

          (D) in the event that the Company elects, pursuant to Section 1502
     hereof, to pay the Change in Control Purchase Price to be paid as of such
     Change in Control Purchase Date, in whole or in part, in Common Stock but
     such portion of the Change in Control Purchase Price shall ultimately be
     payable to such Holder entirely in cash because any of the conditions to
     payment of the Change in Control Purchase Price in Common Stock is not
     satisfied prior to the close of business on such Change in Control Purchase
     Date, as set forth in Section 1504 hereof, whether such Holder elects (i)
     to withdraw such Change in Control Purchase Notice as to some or all of the
     2020 Debentures to which such Change in Control Purchase Notice relates
     (stating the Principal Amount and certificate numbers of the 2020
     Debentures as to which such withdrawal shall relate), or (ii) to receive
     cash in respect of the entire Change in Control Purchase Price for all 2020
     Debentures (or portions thereof) to which such Change in Control Purchase
     Price relates, and

     (4) The delivery of such 2020 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.

     If a Holder, in such Holder Repurchase Notice or 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(b)(3), such Holder shall be deemed to have
elected to receive cash in respect of the Optional Repurchase Price for all 2020
Debentures subject to the Holder Repurchase Notice in the circumstances set
forth in such clause (D).



                                       29

<PAGE>   33

     The Company shall purchase from the Holder thereof, pursuant to this
Section 1501, a portion of a 2020 Debenture only 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 2020 Debenture pursuant to
Sections 1502 through 1510 also apply to the purchase of such portion of such
2020 Debenture.

     Notwithstanding anything herein to the contrary, any Holder delivering to a
Paying Agent the Change in Control Purchase Notice contemplated by this
subsection (3) shall have the right to withdraw such Change in Control Purchase
Notice in whole or in a portion thereof that is a Principal Amount of $1,000 or
in 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
1509.

     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 2020 Debentures may be surrendered or delivered for purchase in
accordance with the applicable procedures of the Depositary as in effect from
time to time.

Section 1502. THE COMPANY'S RIGHT TO ELECT MANNER OF PAYMENT OF REPURCHASE
PRICE.

     The Repurchase Price of 2020 Debentures in respect of which a Repurchase
Notice pursuant to Section 1501 has been given, or a specified percentage
thereof, will be paid by the Company, at the election of the Company, with cash
or Common Stock or in any combination of cash and Common Stock, subject to the
conditions set forth in Section 1503, 1504 and 1505 hereof. The Company shall
designate, in the Company Notice delivered pursuant to Section 1505 hereof,
whether the Company will purchase the 2020 Debentures for cash or Common Stock,
or, if a combination thereof, the percentages of 2020 Debentures in respect of
which it will pay in cash and Common Stock; provided that the Company will pay
cash for fractional interests in Common Stock. For purposes of determining the
existence of potential fractional interests, all 2020 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 2020
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
2020 Debentures, except (i) as provided in Section 1504 with regard to the
payment of cash in lieu of fractional Common Stock and (ii) in the event that
the Company is unable to purchase the 2020 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 2020 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

                                       30

<PAGE>   34

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 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.

     At least three Business Days before the Company Notice Date, the Company
shall deliver an Officers' Certificate to the Trustee specifying:

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

     (ii) the information required by Section 1505,

     (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 have been or will be complied with, and

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

Section 1503. PURCHASE WITH CASH.

     On each Repurchase Date, at the option of the Company, the Repurchase Price
of 2020 Debentures in respect of which a Repurchase Notice pursuant to Section
1501 has been given, or a specified percentage thereof, may be paid by the
Company with cash equal to the aggregate Repurchase Price of such 2020
Debentures. If the Company elects to purchase 2020 Debentures with cash, the
Company Notice, as provided in Section 1505, 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 2020 Debentures in respect of which a Repurchase Notice pursuant to Section
1501 has been given, or a specified percentage thereof, may be paid by the
Company by the issuance of a number of shares of Common Stock equal to the
quotient obtained by dividing (i) the amount of cash to which the Holders 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 2020 Debentures
in cash by (ii) either (A) the Market Price of a share of Common Stock in the
event of an Optional Repurchase or (B) 95% of the Market Price of a share of
Common Stock in the event of a Change of Control Purchase, subject to the next
succeeding paragraph.

     The Company will not issue a fractional share 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


                                       31
<PAGE>   35


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. It is understood that if a Holder elects to have more than one 2020
Debenture repurchased, the number of shares of Common Stock shall be based on
the aggregate amount of 2020 Debentures to be repurchased. If the Company elects
to purchase the 2020 Debentures 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 2020
Debentures pursuant to this Article Fifteen through the issuance of Common Stock
shall be conditioned upon:

     (i) the Company 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 2020 Debentures with Common Stock as
provided herein;

     (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 Officers' 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 Common Stock to be issued by
the Company in payment of the Repurchase Price in respect of 2020 Debentures has
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 2020
Debentures, will be validly issued, fully paid and non-assessable and, to the
best of 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 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 Officers' Certificate shall also set forth the number of shares of
Common Stock to be issued for each $1,000 Principal Amount of 2020 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. 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 foregoing conditions 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 2020 Debentures pursuant to
this Article

                                       32

<PAGE>   36

Fifteen in whole or in part through the issuance of Common Stock, the Company
shall pay, without further notice, the entire Repurchase Price of the 2020
Debentures of such Holder or Holders in cash. The "Market Price" 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 of any event described in Section 1405, during
the period commencing on the first of such trading days during such five trading
day period and ending on such Repurchase Date.

     The "Sale Price" of the Common Stock on any date 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 traded or, if the Common Stock is not listed on a United States
national or regional securities exchange, as reported by the Nasdaq National
Market 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 at the time specified in Section 1503 or 1504, as applicable (the
"Company Notice"). Such Company Notice shall state the manner of payment elected
and shall contain the following information:

     In the event 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 value, based on
the calculation in the first paragraph of Section 1504, equal to such specified
percentage of the Repurchase Price of the 2020 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 price;

'

                                       33

<PAGE>   37

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

     (C) that the 2020 Debentures as to which a Repurchase Notice has been given
may be converted pursuant to Article Fourteen hereof only if the applicable
Repurchase Notice has been withdrawn in accordance with the terms of this
Indenture;

     (D) that 2020 Debentures must be surrendered to the Paying Agent to collect
payment;

     (E) that the Repurchase Price for any 2020 Debenture as to which a Holder
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
2020 Debenture as described in (D);

     (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 2020 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 1509).

     At the Company's request, 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.

Section 1506. COVENANTS OF THE COMPANY.

     All Common Stock delivered upon purchase of the 2020 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 or cause to have quoted any Common Stock to be issued to
purchase 2020 Debentures on the principal national securities exchange or
over-the-counter or other domestic market on which the Common Stock is then
listed 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 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 2020 Debentures to be purchased on the applicable Repurchase Date pursuant
to this Article Fifteen.


                                       34

<PAGE>   38

     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. Subject to Section 1504, 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 2020 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 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 2020 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 2020 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
2020 Debenture (provided the conditions in Section 1501 have been satisfied) and
(y) the time of delivery of such 2020 Debenture to the Paying Agent by the
Holder thereof in the manner required by Section 1501. 2020 Debentures in
respect of which a Repurchase Notice has been given 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 last
Business Day prior to the applicable Repurchase Date specifying:

     (1) the certificate number of the 2020 Debenture in respect of which such
notice of withdrawal is being submitted;

     (2) the Principal Amount of the 2020 Debenture with respect to which such
notice of withdrawal is being submitted; and


                                       35
<PAGE>   39

     (3) the Principal Amount, if any, of such 2020 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(a)(1)(D) or 1501(b)(3)(D) or (ii) a conditional withdrawal containing the
information set forth in Section 1501(a)(1)(D) or 1501(b)(3)(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 2020 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 2020 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 2020 Debentures). The Paying Agent will promptly return to
the respective Holders thereof any (x) 2020 Debentures with respect to which a
Repurchase Notice has been withdrawn in compliance with this Indenture, or (y)
except to the extent such 2020 Debentures are being paid in shares of Common
Stock, any 2020 Debentures 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 2020 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 Repurchase Date, the
Company shall deposit with the Trustee or with the Paying Agent an amount of
money (in immediately available funds) and/or Common Stock, if permitted
hereunder, sufficient to pay the aggregate Repurchase Price of all of the 2020
Debentures or portions thereof which are to be purchased as of the Repurchase
Date. If a Paying Agent holds, in accordance with the terms hereof, money,
and/or shares of Common Stock sufficient to pay the Repurchase Price of any 2020
Debenture for which a Repurchase Notice has been tendered and not withdrawn in
accordance with this Indenture then, on the Repurchase Date, such 2020 Debenture
will cease to be Outstanding and the rights of the Holder in respect thereof
shall terminate (other than the right to receive the Repurchase Price as
aforesaid).

     The manner in which the deposit required by this Section 1510 is made by
the Company shall be at the option of the Company, provided that such deposit
shall be made in a manner such that the Trustee or a Paying Agent shall have
immediately available funds and/or shares of Common Stock by 11:00 a.m. (New
York City time) on the Repurchase Date.


                                       36
<PAGE>   40

Section 1511. SECURITIES REPURCHASED IN PART.

     Any 2020 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 2020 Debenture, without service charge, a new 2020 Debenture or 2020
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 2020 Debenture so surrendered which is not purchased.

Section 1512. COMPLY WITH SECURITIES LAWS UPON PURCHASE OF SECURITIES.

     Unless the staff of the SEC shall issue a letter stating that it will take
no action against the Company if it does not comply, in connection with any
offer to purchase or purchase of 2020 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 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
2020 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 must look to the Company for payment as general creditors, unless an
applicable abandoned property law designates another Person.

Section 1514. CONVERSION ARRANGEMENT ON REPURCHASE.

     Any Securities required to be repurchased under this Article Fifteen,
unless surrendered for conversion before the close of business on the Business
Day prior to the Repurchase Date, may be deemed to be purchased from the Holders
of such Securities for an amount in cash not less than the Repurchase Price, by
one or more investment bankers

                                       37

<PAGE>   41

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 Trustee in trust for such Holders. The Paying
Agent shall hold and pay to the Holders whose 2020 Debentures are repurchased
any such amount paid to it for purchase in the same manner as it would money
deposited with it by the Company for the repurchase of 2020 Debentures. Without
the Paying Agent's prior written consent, no arrangement between the Company and
such purchasers for the purchase and conversion of any 2020 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 2020 Debentures between the
Company and such purchasers, including 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.


                                 ARTICLE SIXTEEN

                          SPECIAL TAX EVENT CONVERSION

Section 1601. 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, whichever is
later (the "Option Exercise Date"), at the option of the Company with respect to
its 2020 Debentures only, interest in lieu of future Original Issue Discount
shall accrue at the rate of 3.5% 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 semiannually on each Interest Payment Date to holders of record
at the close of business on each 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 on
which interest has been paid or, if no interest has been paid, from the Option
Exercise Date. Within 15 days of 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 2020 Debentures. From and after the Option Exercise Date, (i)
the Company shall be obligated to pay at the Stated Maturity of the 2020
Debentures, 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 2020 Debenture. 2020 Debentures authenticated and delivered
after the


                                       38

<PAGE>   42

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 2020 Debentures to
interest-bearing 2020 Debentures.

                                  ARTICLE THREE
                            MISCELLANEOUS PROVISIONS

SECTION 301. INTEGRAL PART.

     This First Supplemental Indenture constitutes an integral part of the
Indenture.

SECTION 302. GENERAL DEFINITIONS.

     For all purposes of this First 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 First Supplemental Indenture.

SECTION 303. ADOPTION, RATIFICATION AND CONFIRMATION.

     The Indenture, as supplemented and amended by this First Supplemental
Indenture, is in all respects hereby adopted, ratified and confirmed.

SECTION 304. COUNTERPARTS.

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

SECTION 305. GOVERNING LAW.

     THIS FIRST SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.


                                       39
<PAGE>   43



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


                                            PERKINELMER, INC.

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


                                            BANK ONE TRUST COMPANY, N.A.


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




                                       40

<PAGE>   44



COMMONWEALTH OF MASSACHUSETTS

COUNTY OF _____________

     On the ____ day of August, 2000, before me personally came ______________,
to me known, who, being by me duly sworn, did depose and say that he is
____________________ of PERKINELMER, INC., one of the corporations described in
and which executed the foregoing instrument; that he knows the seal of said
corporation; that the seal affixed to said instrument is such corporate seal;
that it was so affixed by authority of the Board Directors of said corporation,
and that he signed his name thereto by like authority.


                                  -----------------------------------
                                                Notary







                                       41


<PAGE>   45


STATE OF NEW YORK

COUNTY OF NEW YORK

     On the ____ day of August, 2000, before me personally came ______________,
to me known, who, being by me duly sworn, did depose and say that such person is
an authorized officer of Bank One Trust Company, N.A., one of the corporations
described in and which executed the foregoing instrument; that he or knows the
seal of said corporation; that the seal affixed to said instrument is such
corporate seal; that it was so affixed by authority of the Board Directors of
said corporation, and that such person signed his or her name thereto by like
authority.

                                    -----------------------------------
                                                  Notary




                                       42



<PAGE>   46

                                                                         ANNEX A

                                 GLOBAL SECURITY


                   FORM OF ZERO COUPON CONVERTIBLE DEBENTURES
                                 DUE AUGUST 2020

                                PERKINELMER, INC.

Issue Date:  August 7, 2000                            Maturity:  August 7, 2020

Principal Amount:  $_______                                    CUSIP:  714046AA7

Original Issue Discount:  $500.40                           Issue Price: $499.60
(per $1,000 Principal Amount)                      (per $1,000 Principal Amount)

Registered: No. R-

     Unless this certificate is presented by an authorized representative of The
Depository Trust Company (55 Water Street, New York, New York) to the issuer 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 requested
by an authorized representative of The Depository Trust Company and any payment
is made to Cede & Co., 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.

     Unless and until it is exchanged in whole or in part for the individual
Securities represented hereby, this Global Security may not be transferred
except as a whole by the Depositary to a nominee of the Depositary or by a
nominee of the Depositary to the Depositary or another nominee of the Depositary
or by the Depositary or any such nominee to a successor Depositary or a nominee
of such successor Depositary.

     PerkinElmer, Inc., a Massachusetts corporation (herein called the
"Company", which term includes any successor corporation under the indenture
hereinafter referred to), for value received, hereby promises to pay to Cede &
Co., or registered assigns, the principal sum of ($_________) on August 7, 2020.
The principal of this Security shall not bear interest, except in the case of
default in payment of principal upon acceleration, redemption 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.



                                       1


<PAGE>   47


     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.

     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.

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

Dated:  August 7, 2000


                                           PERKINELMER, INC.


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




--------------------------------
Corporate Secretary




                                       2

<PAGE>   48


                     TRUSTEE'S CERTIFICATE OF AUTHENTICATION

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

                                           Bank One Trust Company, N.A.
                                           as Trustee



                                           ---------------------------------
                                           Authorized Signature






                                       3
<PAGE>   49


                       [FORM OF REVERSE SIDE OF SECURITY]

                                PERKINELMER, INC.

                ZERO COUPON CONVERTIBLE DEBENTURE DUE AUGUST 2020

     This Security is one of a duly authorized issue of senior unsecured
securities of the Company (herein called the "Securities"), issued and to be
issued in one or more series under an Indenture, dated as of August 7, 2000, as
amended by the First Supplemental Indenture thereto, dated as of August 7, 2000
(as so amended, herein called the "Indenture"), between the Company and Bank One
Trust Company, N.A., as Trustee (herein called 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. This
Security is one of the series designated on the face hereof, limited in
aggregate principal amount at Stated Maturity to $920,737,000.

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 3.5% 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 the Security), in the period during which a Security remains
outstanding, shall accrue at 3.5% per annum, on a semiannual bond equivalent
basis using a 360- day year composed of twelve 30-day months, from the Issue
Date of this Security.

METHOD OF PAYMENT

     Cash payments in respect of principal, Original Issue Discount and
interest, if any, on the Securities shall be made by the Company in immediately
available funds. Payments may be made in stock in certain circumstances as set
forth in the Indenture.



                                       4

<PAGE>   50


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, after August 7, 2003.

     The table below shows Redemption Prices of a Security per $1,000 Principal
Amount at Stated Maturity on the dates shown below, 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.

                         (1)                (2)                (3)
--------------------------------------------------------------------------------
                                          Accrued
                   Debenture Issue     Original Issue      Redemption
Redemption Date         Price             Discount         Price(1)+(2)
--------------------------------------------------------------------------------
August 7, 2003         499.60              54.81              554.41
August 7, 2004         499.60              74.38              573.98
August 7, 2005         499.60              94.65              594.25
August 7, 2006         499.60             115.63              615.23
August 7, 2007         499.60             137.35              636.95
August 7, 2008         499.60             159.84              659.44
August 7, 2009         499.60             183.12              682.72
August 7, 2010         499.60             207.22              706.82
August 7, 2011         499.60             232.18              731.78
August 7, 2012         499.60             258.01              757.61
August 7, 2013         499.60             284.76              784.36
August 7, 2014         499.60             312.46              812.06
August 7, 2015         499.60             341.13              840.73
August 7, 2016         499.60             370.81              870.41
August 7, 2017         499.60             401.54              901.14
August 7, 2018         499.60             433.36              932.96
August 7, 2019         499.60             466.30              965.90
August 7, 2020         499.60             500.40             1000.00


     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 date of such conversion to the
Redemption Date; but in no event will this Security be redeemable before August
7, 2003.

     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


                                       5
<PAGE>   51

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.

NOTICE OF OPTIONAL REDEMPTION BY THE COMPANY

     Notice of optional redemption by the Company will be mailed by first-class
mail at least 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
in denominations larger than $1,000 Principal Amount 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 the Security is converted to an
interest-bearing debenture) ceases to accrue on Securities or portions thereof
called for redemption.

CONVERSION

     A Holder of a Security may convert the Security into Common Stock 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 exercising the option of such Holder to require
the Company to purchase such Security may be converted only if such notice of
exercise is withdrawn in accordance with the terms of the Indenture. The initial
conversion price is $170.11 per share of Common Stock, subject to adjustment in
certain events described in the Indenture. This is equivalent to a conversion
rate of 5.8785 shares of Common Stock per $1,000 Principal Amount of Securities
at Stated Maturity. The Company will deliver cash or a check in lieu of any
fractional Common Stock.

     In the event the Company exercises its option pursuant to Section 1601 of
the Indenture to have interest in lieu of Original Issue Discount accrue on the
Security following a Tax Event, the Holder will be entitled on conversion to
receive the same number 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 (except Securities
or portions of Securities to be redeemed on a Redemption Date occurring during
the period from the close of business on a Regular Record Date and ending on the
opening of business on the first Business Day after the next Interest Payment
Date, or if this Interest Payment Date is not a Business Day, the second
Business Day after the Interest Payment Date) 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.



                                       6
<PAGE>   52

     A Holder may convert a portion of a Security if the Principal Amount 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 a 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",
from the later of (x) the date of such exercise and (y) the date on which
interest was last paid) 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 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 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 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 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.

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 of such part is $1,000
or an integral multiple of $1,000 in excess thereof) of the Securities held by
such Holder 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 Change in Control Purchase Price may be paid, at the option
of the Company, in cash or by the issuance of Common Stock as provided in
Article Fifteen of the Indenture, or in any combination thereof. 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 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


                                       7
<PAGE>   53

Purchase Price shall be equal to the Restated Principal Amount plus accrued and
unpaid interest from the date of conversion to the Change in Control Purchase
Date.

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, the Securities held
by such Holder on the following Repurchase Dates and at the following Repurchase
Prices per $1,000 Principal Amount, upon delivery by the Holder 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 such Repurchase Date and upon
delivery of the Securities to the Paying Agent by the Holder as set forth in the
Indenture.





                                       8
<PAGE>   54



              REPURCHASE DATE               REPURCHASE PRICE
              ---------------               ----------------

               August 7, 2003                   $554.41
               August 7, 2010                   $706.82

     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 Article Fifteen of 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 last Business Day prior to the Repurchase Date in accordance with the
provisions of the Indenture.

     If cash or Common Stock 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 by 11:00 a.m. New York City time on the
Repurchase Date, Original Issue Discount 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, whichever is later
(the "Option Exercise Date"), at the option of the Company, interest in lieu of
future Original Issue Discount shall accrue at the rate of 3.5% per annum on a
Principal Amount per Security (the "Restated Principal Amount") equal to the
Issue Price plus Original Issue Discount accrued through the Option Exercise
Date and shall be payable semiannually on February 15 and August 15, of each
year (each an "Interest Payment Date") to holders of record at the close of
business on February 1 or August 1 (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, if no interest has been paid,
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 for such interest at the office or agency of the Company maintained for
such purpose. Each installment of interest on any Security shall be paid

                                       9

<PAGE>   55

in same-day funds by transfer to an account maintained by the payee located
inside the United States.

     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 called for redemption, or as to which a Repurchase Notice
has been given but not withdrawn, 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 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.

     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.


                                       10

<PAGE>   56

AMENDMENT, SUPPLEMENT AND WAIVER

     The Indenture permits, with certain exceptions as therein provided, the
amendment thereof and the modification of the rights and obligations of the
Company and the rights of the Holders of the Securities of each series to be
affected under the Indenture at any time by the Company and the Trustee with the
consent of the Holders of a majority in principal amount of the Securities at
the time Outstanding of each series to be affected. The Indenture also contains
provisions permitting the Holders of specified percentages in principal amount
of the Securities of each series at the time Outstanding, on behalf of the
Holders of all Securities of such series, to waive compliance by the Company
with certain past defaults under the Indenture and their consequences. Any such
consent or waiver by the Holder of this Security shall be conclusive and binding
upon such Holder and upon all future Holders of this Security and of any
Security issued upon the registration of transfer hereof or in exchange hereof
or in lieu hereof, whether or not notation of such consent or waiver is made
upon this Security.

SUCCESSOR CORPORATION

     When a successor corporation 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 corporation will (except in certain
circumstances specified in the Indenture) be released from those obligations.

DEFAULTS AND REMEDIES

     If an Event of Default with respect to Securities of this series shall
occur and be continuing, all unpaid Issue Price plus accrued Original Issue
Discount through the acceleration date (or, if the Security has been converted
to an interest bearing debenture, the Restated Principal Amount plus accrued and
unpaid interest from the date of conversion to the acceleration date) of the
Securities of this series may be declared due and payable in the manner and with
the effect provided in the Indenture.

NO RECOURSE AGAINST OTHERS

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

AUTHENTICATION

     This Security shall not be valid until the Trustee or an authenticating
agent manually signs the certificate of authentication on the other side of this
Security.


                                       11
<PAGE>   57

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.

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.





                                       12

<PAGE>   58



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 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.



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