Document:

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                                                                     EXHIBIT 4-Y

                          FOURTH SUPPLEMENTAL INDENTURE

                                     between

                             HERCULES INCORPORATED,
                                    as Issuer

                                       and

                            THE CHASE MANHATTAN BANK,
                                   as Trustee

                          Dated as of December 23, 1999

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                                TABLE OF CONTENTS

                                   ARTICLE 1
                                  DEFINITIONS

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SECTION 1.01.  Definition of Terms................................................................................2

                                    ARTICLE 2
          GENERAL TERMS AND CONDITIONS OF THE SUBORDINATED DEBENTURES

SECTION 2.01.  Designation and Principal Amount...................................................................5
SECTION 2.02.  Maturity...........................................................................................5
SECTION 2.03.  Form and Payment; Minimum Transfer Restriction.....................................................5
SECTION 2.04.  Exchange and Registration of Transfer of Securities; Restrictions on
                  Transfers; Depository...........................................................................6
SECTION 2.05.  Interest...........................................................................................8

                                    ARTICLE 3
                   REDEMPTION OF THE SUBORDINATED DEBENTURES

SECTION 3.01.  Redemption.........................................................................................9
SECTION 3.02.  No Sinking Fund....................................................................................9

                                    ARTICLE 4
                      EXTENSION OF INTEREST PAYMENT PERIOD

SECTION 4.01.  Extension of Interest Payment Period...............................................................9
SECTION 4.02.  Notice of Extension...............................................................................10

                                    ARTICLE 5
                                    EXPENSES

SECTION 5.01.  Payment of Expenses...............................................................................10
SECTION 5.02.  Payment upon Resignation or Removal...............................................................11

                                    ARTICLE 6
                                     NOTICE

SECTION 6.01.  Notice by the Company.............................................................................11
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                                    ARTICLE 7
                     CONVERSION OF SUBORDINATED DEBENTURES

SECTION 7.01.  Conversion Rights.................................................................................12

                                    ARTICLE 8
                        FORM OF SUBORDINATED DEBENTURES

SECTION 8.01.  Form of Subordinated Debenture....................................................................12

                                    ARTICLE 9
                   ORIGINAL ISSUE OF SUBORDINATED DEBENTURES

SECTION 9.01.  Subordinated Debentures...........................................................................12

                                   ARTICLE 10
                        EVENTS OF DEFAULT; ACCELERATION

SECTION 10.01.  Events of Default................................................................................12
SECTION 10.02.  Acceleration.....................................................................................12

                                   ARTICLE 11
                                 MISCELLANEOUS

SECTION 11.01.  Ratification of Base Indenture; Fourth Supplemental Indenture Controls...........................13
SECTION 11.02.  Trustee Not Responsible for Recitals.............................................................13
SECTION 11.03.  Governing Law....................................................................................13
SECTION 11.04.  References to Co-Chief Executive Officer.........................................................13
SECTION 11.05.  Severability.....................................................................................13
SECTION 11.06.  Counterparts.....................................................................................13
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EXHIBIT A-1       -   Form of Subordinated Debenture

                                      -ii-
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         FOURTH SUPPLEMENTAL INDENTURE, dated as of December 23, 1999 (the
"FOURTH SUPPLEMENTAL INDENTURE"), between Hercules Incorporated, a Delaware
corporation (the "COMPANY"), and The Chase Manhattan Bank, a New York banking
corporation, as trustee (the "TRUSTEE") under the Junior Subordinated Debentures
Indenture dated as of November 12, 1998 between the Company and the Trustee (the
"BASE INDENTURE" and together with this Fourth Supplemental Indenture, the
"INDENTURE").

         WHEREAS, the Company executed and delivered the Base Indenture to the
Trustee to provide for the future issuance of the Company's unsecured junior
subordinated debentures (the "DEBENTURES") to be issued from time to time in one
or more series as might be determined by the Company under the Base Indenture,
in an unlimited aggregate principal amount which may be authenticated and
delivered as provided in the Base Indenture;

         WHEREAS, pursuant to the terms of the Indenture, the Company desires to
provide for the establishment of a new series of its Debentures to be known as
its Floating Rate Junior Subordinated Deferrable Interest Debentures due 2000
(the "SUBORDINATED DEBENTURES"), the form and substance of such Subordinated
Debentures and the terms, provisions and conditions thereof to be set forth as
provided in the Base Indenture and this Fourth Supplemental Indenture;

         WHEREAS, Hercules Trust VI, a Delaware statutory business trust (the
"TRUST"), has offered to J.P. Morgan Securities Inc., as initial purchaser (the
"INITIAL PURCHASER"), $170,000,000 aggregate liquidation amount of its Floating
Rate Preferred Securities (the "PREFERRED SECURITIES"), representing undivided
beneficial interests in the assets of the Trust, for resale to "qualified
institutional buyers" under Rule 144A, and proposes to invest the proceeds from
such offering, together with the proceeds of the issuance and sale by the Trust
to the Company of $5,258,000 aggregate liquidation amount of its Common
Securities, in $175,258,000 aggregate principal amount of the Subordinated
Debentures; and

          WHEREAS, the Company has requested that the Trustee execute and
deliver this Fourth Supplemental Indenture, and all requirements necessary to
make this Fourth Supplemental Indenture a valid instrument in accordance with
its terms, and to make the Subordinated Debentures, when executed by the Company
and authenticated and delivered by the Trustee, the valid obligations of the
Company, have been performed, and the execution and delivery of this Fourth
Supplemental Indenture has been duly authorized in all respects.

         NOW THEREFORE, in consideration of the purchase and acceptance of the
Subordinated Debentures by the Holder thereof, and for the purpose of setting
forth, as provided in the Indenture, the form and substance of the Subordinated
Debentures and the terms, provisions and conditions thereof, the Company
covenants and agrees with the Trustee as follows:

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                                    ARTICLE 1
                                   DEFINITIONS

         SECTION 1.01. Definition of Terms. For all purposes of this Fourth
Supplemental Indenture, except as otherwise expressly provided or unless the
context otherwise requires:

                  (a) the terms which are defined in the Base Indenture have the
         same meanings when used in this Fourth Supplemental Indenture;

                  (b) the terms defined in this Article have the meaning
         assigned to them in this Article and include the plural as well as the
         singular;

                  (c) all other terms used herein which are defined in the Trust
         Indenture Act, whether directly or by reference therein, have the
         meanings assigned to them therein;

                  (d) all accounting terms not otherwise defined herein have the
         meanings assigned to them in accordance with GAAP, and, except as
         otherwise herein expressly provided, the term "GAAP" with respect to
         any computation required or permitted hereunder shall mean such
         accounting principles as are generally accepted in the United States of
         America at the date of such computation;

                  (e) a reference to a Section or Article is to a Section or
         Article of this Fourth Supplemental Indenture;

                  (f) the words "herein" "hereof" and "hereunder" and other
         words of similar import refer to this Fourth Supplemental Indenture as
         a whole and not to any particular Article, Section or other
         subdivision;

                  (g) headings are for convenience of reference only and do not
         affect interpretation; and

                  (h) the following terms have the meanings given to them in the
         Trust Agreement:

                      ADMINISTRATIVE TRUSTEE
                      AFFILIATE
                      COMMON SECURITIES
                      DELAWARE TRUSTEE
                      LIKE AMOUNT
                      LIQUIDATION AMOUNT
                      PERSON
                      PORTAL MARKET
                      PROPERTY TRUSTEE
                      PURCHASE AGREEMENT
                      RULE 144A
                      SECURITIES ACT.

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         "ADDITIONAL INTEREST" has the meaning set forth in Section 2.05(d).

         "BUSINESS DAY" means any day other than a Saturday, Sunday or other day
on which banking institutions in The City of New York or Wilmington, Delaware
are authorized or required by law, regulation or executive order to close;
provided, however, that with respect to LIBOR interest determinations,
calculations and payments, such day is also a London Banking Day.

         "CALCULATION AGENT" means The Chase Manhattan Bank or in the event of
resignation by or removal of The Chase Manhattan Bank, any replacement as
Calculation Agent appointed by the Company.

         "CREDIT AGREEMENT" means the Amended and Restated Credit Agreement
dated as of April 19, 1999 among the Company, certain subsidiaries of the
Company from time to time parties thereto, the several lenders from time to time
parties thereto, NationsBank, N.A., as Administrative Agent, Bank of America
Canada, as Canadian Administrative Agent, and The Chase Manhattan Bank, Morgan
Guaranty Trust Company of New York and Citibank, N.A., as Co-Syndication Agents,
as amended, supplemented, modified or superseded from time to time.

         "DEPOSITORY" has the meaning set forth in the Base Indenture.

         "DETERMINATION DATE" means two London Banking Days prior to the
applicable Interest Payment Date.

         "DISSOLUTION EVENT" means the dissolution of the Trust pursuant to
Section 8.1 of the Trust Agreement, and the distribution of the Subordinated
Debentures held by the Property Trustee to the holders of the Preferred
Securities issued by the Trust pro rata in accordance with the Trust Agreement.

         "EXTENDED INTEREST PAYMENT PERIOD" has the meaning set forth in Section
4.01.

         "GAAP" has the meaning set forth in the Base Indenture.

         "GLOBAL DEBENTURE" has the meaning set forth in the Base Indenture.

         "GLOBAL SUBORDINATED DEBENTURE" has the meaning set forth in Section
2.04(a)(i).

         "GUARANTEE TRUSTEE" means the Preferred Securities Guarantee Trustee as
defined in the Preferred Securities Guarantee Agreement dated as of December 23,
1999 between Hercules Incorporated, as Guarantor, and The Chase Manhattan Bank,
as Preferred Securities Guarantee Trustee.

         "HOLDER" has the meaning set forth in the Base Indenture.

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         "INTEREST PAYMENT DATE" has the meaning set forth in Section 2.05(b).

         "INTEREST RATE" has the meaning set forth in Section 2.05(a).

         "LIBOR" means, with respect to an interest period commencing on an
Interest Payment Date (in the following order of priority):

         (a) the rate (expressed as a percentage per annum) for Eurodollar
deposits having a three-month maturity that appears on Telerate page 3750 as of
11:00 a.m. (London time) on the Determination Date;

         (b) if such rate does not appear on Telerate page 3750 as of 11:00 a.m.
(London time) on the Determination Date, the Calculation Agent will request the
principal London offices of four leading banks in the London interbank market as
selected by the Calculation Agent in consultation with the Company to provide
such banks' offered quotations (expressed as percentages per annum) to prime
banks in the London interbank market for Eurodollar deposits having a
three-month maturity as of 11:00 a.m. (London time) on such Determination Date,
and if at least two quotations are provided, LIBOR will be the arithmetic mean
of such quotations (rounded upwards if necessary to the fifth decimal place);

         (c) if fewer than two such quotations are provided as requested in
clause (b) above, the Calculation Agent will request four major New York City
banks selected by the Calculation Agent in consultation with the Company to
provide such banks' offered quotations (expressed as percentages per annum) to
leading European banks for loans in Eurodollars as of 11:00 a.m. (New York City
time) on such Determination Date, and if at least two quotations are provided,
LIBOR will be the arithmetic mean of such quotations (rounded upwards if
necessary to the fifth decimal place); and

         (d) if fewer than two such quotations are provided as requested in
clause (c) above, LIBOR will be LIBOR as in effect during the preceding interest
period.

         "LONDON BANKING DAY" means any day, other than a Saturday or Sunday, on
which banks are open for business (including dealings in deposits in U.S.
dollars) in London.

         "MATURITY DATE" means December 29, 2000.

         "REGULAR RECORD DATE" has the meaning set forth in Section 2.05(c).

         "RESTRICTED SECURITY" has the meaning set forth in Section 2.04(c).

         "SENIOR BANK DEBT ACCELERATION" means an acceleration under the Credit
Agreement resulting in the obligations of the Company under the Credit Agreement
becoming or having been declared due and payable under Section 6 of the Credit
Agreement before such obligations would otherwise have been due and payable.

                                       4
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         "TRANSFER RESTRICTION TERMINATION DATE" means the first date on which
the Subordinated Debentures (other than Subordinated Debentures acquired by the
Company or any Affiliate thereof) may be sold pursuant to Rule 144(k).

         "TRUST AGREEMENT" means the Amended and Restated Trust Agreement of
Hercules Trust VI, a Delaware statutory business trust, dated as of December 23,
1999.

         "TRUST SECURITIES" means the Preferred Securities and Common Securities
of the Trust.

         "U.S. DOLLAR," "DOLLAR," "U.S.$," "$" and "USD" means the lawful
currency of the United States of America.

                                    ARTICLE 2
           GENERAL TERMS AND CONDITIONS OF THE SUBORDINATED DEBENTURES

         SECTION 2.01. Designation and Principal Amount. There is hereby
authorized a series of Debentures designated the "Floating Rate Junior
Subordinated Deferrable Interest Debentures due 2000," limited in aggregate
principal amount to $309,279,000, which amount shall be as set forth in any
written order of the Company for the authentication and delivery of Subordinated
Debentures pursuant to Section 2.03 of the Base Indenture, except for
Subordinated Debentures authenticated and delivered upon registration of
transfer of, or in exchange for, or in lieu of, other Subordinated Debentures
under the terms of the Indenture. Of such aggregate principal amount,
$175,258,000 is authenticated and delivered as of the date hereof, and the
remaining $134,021,000 of the Subordinated Debentures is issuable only in
connection with the Trust's right under the Trust Agreement to issue additional
Preferred Securities and Common Securities.

         SECTION 2.02. Maturity. The principal of the Subordinated Debentures
shall be due and payable on the Maturity Date.

         SECTION 2.03. Form and Payment; Minimum Transfer Restriction. (a)
Except as provided in Section 2.04, the Subordinated Debentures shall be issued
in fully registered certificated form without coupons in denominations of
$1,000,000 in principal amount and integral multiples of $1,000 thereof.
Principal and interest on the Subordinated Debentures issued in certificated
form will be payable by check or wire transfer, the transfer of such
Subordinated Debentures will be registrable and such Subordinated Debentures
will be exchangeable for Subordinated Debentures bearing identical terms and
provisions at the office or agency of the Trustee; provided, however, that
payment of interest may be made at the option of the Company by check mailed to
the Holder at such address as shall appear in the Register. Notwithstanding the
foregoing, so long as the Holder of any Subordinated Debentures is the Property
Trustee, the payment of the principal of and interest (including any Additional
Interest, if any) on such Subordinated Debentures held by the Property Trustee
will be made at such place and to such account as may be designated by the
Property Trustee.

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         (b) The Subordinated Debentures may be transferred or exchanged only in
minimum denominations of $1,000,000 and integral multiples of $100,000 in excess
thereof, and any attempted transfer, sale or other disposition of Subordinated
Debentures in a denomination of less than $1,000,000 shall be deemed to be void
and of no legal effect whatsoever.

         SECTION 2.04. Exchange and Registration of Transfer of Securities;
Restrictions on Transfers; Depository. (a) If distributed to holders of
Preferred Securities in connection with a Dissolution Event, the Subordinated
Debentures will be issued in the same form as the Preferred Securities that such
Subordinated Debentures replace in accordance with the following procedures.

                  (i) If the Preferred Securities are held in global form, the
         Subordinated Debentures shall be presented to the Trustee by the
         Property Trustee in exchange for a Global Debenture in an aggregate
         principal amount equal to the aggregate principal amount of all
         outstanding Subordinated Debentures (a "GLOBAL SUBORDINATED
         DEBENTURE"), to be registered in the name of the Depository, or its
         nominee, and delivered by the Property Trustee to the Depository for
         crediting to the accounts of its participants pursuant to the
         instructions of the Administrative Trustees. The Company upon any such
         presentation shall execute a Global Subordinated Debenture in such
         aggregate principal amount and deliver the same to the Trustee for
         authentication and delivery in accordance with the Indenture. Payments
         on the Subordinated Debentures issued as a Global Subordinated
         Debenture will be made to the Depository.

                  (ii) If the Preferred Securities are held in certificated
         form, the Subordinated Debentures shall be presented to the Trustee by
         the Property Trustee and each outstanding Preferred Security
         certificate will be deemed to represent a beneficial interest in such
         Subordinated Debenture in an aggregate principal amount equal to the
         aggregate Liquidation Amount of the Preferred Securities represented by
         such Preferred Security certificate. When the holder of a Preferred
         Security certificate presents such certificate for transfer or
         reissuance, such certificate will be canceled and a Subordinated
         Debenture, registered in the name of such holder or such holder's
         transferee, as the case may be, in an aggregate principal amount equal
         to the aggregate Liquidation Amount of the canceled certificate, will
         be executed by the Company and delivered to the Trustee for
         authentication and delivery in accordance with the Indenture. On issue
         of such Subordinated Debentures, Subordinated Debentures with an
         equivalent aggregate principal amount that were presented by the
         Property Trustee to the Trustee will be deemed to have been canceled.

         (b) Any Global Subordinated Debenture may be endorsed with or have
incorporated in the text thereof such legends or recitals or changes not
inconsistent with the provisions of this Indenture as may be required by the
Depository, by a national securities exchange or by the National Association of
Securities Dealers, Inc. in order for the Subordinated Debentures to be
tradeable on the PORTAL Market or as may be required for the Subordinated
Debentures to be tradeable on any other market developed for trading of
securities pursuant to Rule 144A or

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required to comply with any applicable law or any regulation thereunder or with
the rules and regulations of any securities exchange upon which the Subordinated
Debentures may be listed or traded or to conform with any usage with respect
thereto, or to indicate any special limitations or restrictions to which any
particular Subordinated Debentures are subject.

         (c) Each Subordinated Debenture that bears or is required to bear the
legend set forth in this Section 2.04(c) (a "RESTRICTED SECURITY") shall be
subject to the restrictions on transfer provided in the legend set forth in this
Section 2.04(c), unless such restrictions on transfer shall be waived by the
written consent of the Company, and the Holder of each Restricted Security, by
such Holder's acceptance thereof, agrees to be bound by such restrictions on
transfer. As used in this Section 2.04(c) and in Section 2.04(d), the term
"transfer" encompasses any sale, pledge, transfer or other disposition of any
Restricted Security.

         Prior to the Transfer Restriction Termination Date, any certificate
evidencing a Subordinated Debenture shall bear a legend in substantially the
following form, unless otherwise agreed by the Company (with written notice
thereof to the Trustee):

         THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933,
         AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS.
         NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE
         REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR
         OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS
         SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION UNDER
         THE SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES LAWS.

         THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES NOT TO
         OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY PRIOR TO THE DATE (THE
         "TRANSFER RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE
         LATER OF THE ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH
         HERCULES INCORPORATED OR ANY AFFILIATED PERSON OF HERCULES INCORPORATED
         WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY)
         UNLESS SUCH OFFER, SALE OR OTHER TRANSFER IS (A) TO HERCULES
         INCORPORATED OR ANY OF ITS SUBSIDIARIES, (B) PURSUANT TO A REGISTRATION
         STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT,
         (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO
         RULE 144A, TO A PERSON WHO IS OR WHO THE HOLDER REASONABLY BELIEVES IS
         A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A UNDER THE
         SECURITIES ACT THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF
         A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE
         TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) TO AN "ACCREDITED
         INVESTOR" (AS DEFINED IN RULE 501(a)(1), (2), (3) OR (7) UNDER THE
         SECURITIES ACT) THAT IS AN INSTITUTIONAL INVESTOR, (E) PURSUANT TO
         OFFERS AND SALES TO NON-U.S. PERSONS THAT OCCUR OUTSIDE THE UNITED
         STATES WITHIN THE MEANING OF REGULATION S UNDER THE SECURITIES ACT OR
         (F) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION FROM THE REGISTRATION
         REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE RIGHT OF HERCULES
         INCORPORATED OR THE

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         TRANSFER AGENT FOR THE SECURITIES PRIOR TO ANY SUCH OFFER, SALE OR
         TRANSFER PURSUANT TO CLAUSES (D), (E) OR (F) TO REQUIRE THE DELIVERY OF
         AN OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION
         SATISFACTORY TO EACH OF THEM. THIS LEGEND WILL BE REMOVED UPON THE
         REQUEST OF THE THEN HOLDER OF THIS SECURITY AFTER THE TRANSFER
         RESTRICTION TERMINATION DATE.

         Following the Transfer Restriction Termination Date, any Subordinated
Debenture or security issued in exchange or substitution therefor (other than
Subordinated Debentures acquired by the Company or any Affiliate) may, upon
surrender of such Subordinated Debenture or security for exchange to the Trustee
in accordance with the provisions of this Section 2.04, be exchanged for a new
Subordinated Debenture or Subordinated Debentures, of like tenor and aggregate
principal amount, which shall not bear the restrictive legend required by this
Section 2.04(c).

         (d) Any Subordinated Debenture that, prior to the Transfer Restriction
Termination Date, is purchased or owned by the Company or any Affiliate thereof
may not be resold by the Company or such Affiliate unless registered under the
Securities Act or resold pursuant to an exemption from the registration
requirements thereof.

         SECTION 2.05. Interest. (a) Interest on the principal amount of each
Subordinated Debenture will accrue and be payable at a rate (the "INTEREST
RATE") per annum, reset quarterly, equal to LIBOR plus 2.45% of such principal
amount. Notwithstanding the foregoing, if the Company fails to pay principal or
interest when due, such overdue amount shall accrue interest, compounded
quarterly, at the then applicable periodic Interest Rate, but only to the extent
permitted by applicable law. The term "INTEREST", as used herein, includes any
such additional interest and Additional Interest unless otherwise stated.

         (b) Interest on the Subordinated Debentures will be payable quarterly
in arrears on March 29, 2000, June 29, 2000, September 29, 2000 and December 29,
2000, commencing March 29, 2000 (each, an "INTEREST PAYMENT DATE"), and will
accrue from and including the most recent date to which interest has been paid
or, if no interest has been paid, from December 23, 1999 (for the Subordinated
Debentures issued on such date), to but excluding the related Interest Payment
Date, except as otherwise described below. If additional Subordinated Debentures
are issued upon the issuance of additional Preferred Securities and Common
Securities as contemplated in Section 2.01, the Company will establish the date
on which interest will begin to accrue and the initial Interest Payment Date
with respect to such additional Subordinated Debentures.

         For the Subordinated Debentures issued on December 23, 1999, the
Interest Rate in effect for the interest period from and including December 23,
1999 to but excluding March 29, 2000 shall be 8 5/8%. The amount of interest
payable for any interest period shall be computed on the basis of the actual
number of days in such period and a year of 360 days. If an Interest Payment
Date is not a Business Day, then such Interest Payment Date will be postponed to
the next

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succeeding Business Day, except if such Business Day is in the next succeeding
calendar month, such Interest Payment Date will be the immediately preceding
Business Day.

         (c) Interest shall be paid to the Person in whose name such
Subordinated Debenture or any predecessor Subordinated Debenture is registered
on the books and records of the Company at the close of business on the Regular
Record Date for such interest installment, which shall be the fifteenth (15th)
day of the month in which the applicable Interest Payment Date falls (the
"REGULAR RECORD DATE"). Notwithstanding the foregoing, so long as the Holder of
the Subordinated Debenture is the Property Trustee, the payment of the principal
of and interest on this Subordinated Debenture will be made at such place and to
such account as may be designated by the Property Trustee.

         (d) If, at any time while the Property Trustee is the Holder of any
Subordinated Debentures, the Trust or the Property Trustee is required to pay
any taxes, duties, assessments or governmental charges of whatever nature (other
than withholding taxes) imposed by the United States, or any other taxing
authority, then, in any such case, the Company will pay as additional interest
("ADDITIONAL INTEREST") on the Subordinated Debentures held by the Property
Trustee, such additional amounts as shall be required so that the net amounts
received and retained by the Trust and the Property Trustee after paying such
taxes, duties, assessments or other governmental charges will be equal to the
amounts the Trust and the Property Trustee would have received had no such
taxes, duties, assessments or other government charges been imposed.

                                    ARTICLE 3
                    REDEMPTION OF THE SUBORDINATED DEBENTURES

         SECTION 3.01. Redemption. The Subordinated Debentures are not subject
to redemption by the Company prior to maturity.

         SECTION 3.02. No Sinking Fund. The Subordinated Debentures are not
entitled to the benefit of any sinking fund.

                                    ARTICLE 4
                      EXTENSION OF INTEREST PAYMENT PERIOD

         SECTION 4.01. Extension of Interest Payment Period. The Company shall
have the right, at any time, and from time to time, during the term of the
Subordinated Debentures to extend the interest payment period of the
Subordinated Debentures (an "EXTENDED INTEREST PAYMENT PERIOD"), provided no
Event of Default has occurred and is continuing with respect to the Subordinated
Debentures, and provided, further, that such Extended Interest Payment Period
must end on an Interest Payment Date and may not extend beyond the Maturity
Date. To the extent permitted by applicable law, interest, the payment of which
has been deferred because of the extension of the Interest Payment Period
pursuant to this Section 4.01, will bear interest

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thereon at the then applicable periodic Interest Rate for each quarterly period
in the Extended Interest Payment Period. At the end of the Extended Interest
Payment Period, the Company shall pay all interest then accrued and unpaid on
the Subordinated Debentures, including any Additional Sums, which shall be
payable to the Holders of the Subordinated Debentures in whose names the
Subordinated Debentures are registered in the Register on the first Regular
Record Date after the end of the Extended Interest Payment Period. Before the
termination of any Extended Interest Payment Period, the Company may shorten or
further extend such Extended Interest Payment Period, provided, however, that
such Extended Interest Payment Period, together with all such previous further
extensions thereof, shall not exceed beyond the Maturity Date. At the
termination of any Extended Interest Payment Period and upon the payment of all
accrued and unpaid interest and any Additional Sums then due, the Company may
elect a new Extended Interest Payment Period, subject to the foregoing
requirements. No interest shall be due and payable during an Extended Interest
Payment Period, except at the end thereof.

         SECTION 4.02.  Notice of Extension.

         (a) If the Property Trustee is the only registered holder of the
Subordinated Debentures at the time the Company selects an Extended Interest
Payment Period, the Company shall give written notice to both the Administrative
Trustees and the Property Trustee of its selection of such Extended Interest
Payment Period in accordance with the notice provisions of Section 4.01 of the
Base Indenture.

         (b) If the Property Trustee is not the only registered holder of the
Subordinated Debentures at the time the Company selects an Extended Interest
Payment Period, the Company shall give the holders of the Subordinated
Debenture's written notice of its selection of such Extended Interest Payment
Period in accordance with the notice provisions of Section 4.01 of the Base
Indenture.

                                    ARTICLE 5
                                    EXPENSES

         SECTION 5.01. Payment of Expenses. In connection with the offering,
sale and issuance of the Subordinated Debentures to the Property Trustee and in
connection with the sale of the Trust Securities by the Trust, the Company, in
its capacity as borrower with respect to the Subordinated Debentures, shall:

         (a) pay all costs and expenses relating to the offering, sale and
issuance of the Subordinated Debentures payable pursuant to the Purchase
Agreement and compensation of the Trustee under the Indenture in accordance with
the provisions of Section 7.06 of the Base Indenture;

         (b) pay all costs and expenses of the Trust (other than payment in
respect of Trust Securities) (including, but not limited to, costs and expenses
relating to the organization of the

                                       10
<PAGE>   14

Trust; the fees and expenses of the Property Trustee and the Delaware Trustee;
the costs and expenses relating to the operation of the Trust, including without
limitation, costs and expenses of accountants, attorneys, statistical or
bookkeeping services, expenses for printing, engraving, computing or accounting
equipment, paying agent(s), registrar(s), transfer agent(s), duplicating and
travel; telephone and other telecommunications expenses; and costs and expenses
incurred in connection with the acquisition, financing, and disposition of Trust
assets);

         (c) pay all costs and expenses of the Trust or Property Trustee related
to the enforcement by the Property Trustee of the rights of the holders of the
Preferred Securities;

         (d) be primarily liable for any indemnification obligations arising
with respect to the Trust Agreement; and

         (e) pay any and all taxes (other than United States withholding taxes
attributable to the Trust or its assets) and all liabilities, costs and expenses
with respect to such taxes of the Trust.

         SECTION 5.02. Payment upon Resignation or Removal. Upon termination of
this Fourth Supplemental Indenture or the Base Indenture or the removal or
resignation of the Trustee pursuant to Section 7.08 of the Base Indenture, the
Company shall pay to the Trustee all amounts accrued to the date of such
termination, removal or resignation. Upon termination of the Trust Agreement or
the removal or resignation of the Delaware Trustee, the Guarantee Trustee or the
Property Trustee, as the case may be, the Company shall pay to the Delaware
Trustee, the Guarantee Trustee or the Property Trustee and their respective
counsel, as the case may be, all amounts accrued to the date of such
termination, removal or resignation.

                                    ARTICLE 6
                                     NOTICE

         SECTION 6.01. Notice by the Company. The Company shall give prompt
written notice to the Trustee of any fact known to the Company that would
prohibit the making of any payment of monies to or by the Trustee in respect of
the Subordinated Debentures pursuant to the provisions of this Article.
Notwithstanding any of the provisions of the Base Indenture or this Fourth
Supplemental Indenture, the Trustee shall not be charged with knowledge of the
existence of any facts that would prohibit the making of any payment of monies
to or by the Trustee in respect of the Subordinated Debentures pursuant to the
provisions of the Base Indenture; provided, however, that if the Trustee shall
not have received the notice provided for in this Article at least two Business
Days prior to the date upon which by the terms hereof any money may become
payable for any purpose (including, without limitation, the payment of the
principal of or interest on any Subordinated Debenture), then, anything herein
contained to the contrary notwithstanding, the Trustee shall have full power and
authority to receive such money and to apply the same to the purposes for which
it was received, and shall not be affected by any notice to the contrary that
may be received by it on or after the second Business Day prior to such date.

                                       11
<PAGE>   15

                                    ARTICLE 7
                      CONVERSION OF SUBORDINATED DEBENTURES

         SECTION 7.01. Conversion Rights. The Subordinated Debentures are not
convertible at any time.

                                    ARTICLE 8
                         FORM OF SUBORDINATED DEBENTURES

         SECTION 8.01. Form of Subordinated Debenture. The Subordinated
Debentures and the Trustee's certificate of authentication shall be
substantially in the form of Exhibit A-1. Exhibit A-1 is hereby incorporated in
and expressly made a part of this Fourth Supplemental Indenture.

                                    ARTICLE 9
                    ORIGINAL ISSUE OF SUBORDINATED DEBENTURES

         SECTION 9.01. Subordinated Debentures. Each Subordinated Debenture
shall be issued in denominations of $1,000,000 and in integral multiples of
$100,000 thereof and may, upon execution of this Fourth Supplemental Indenture,
be executed by the Company and delivered to the Trustee for authentication, and
the Trustee shall thereupon authenticate and make available for delivery said
Subordinated Debentures to or upon the written order of the Company, signed by
its Chief Executive Officer, its President, any Executive Vice President or any
Vice President and its Treasurer or an Assistant Treasurer, without any further
action by the Company.

                                   ARTICLE 10
                         EVENTS OF DEFAULT; ACCELERATION

         SECTION 10.01. Events of Default. A Senior Bank Debt Acceleration shall
be an Event of Default under Section 6.01(h) of the Base Indenture.

         SECTION 10.02. Acceleration. Notwithstanding the provisions of Section
6.02 of the Base Indenture, if a Senior Bank Debt Acceleration shall occur, the
principal of, and any accrued interest on, all the Subordinated Debentures shall
ipso facto become and be immediately due and payable without any declaration or
other act on the part of the Trustee or any Holders of Subordinated Debentures.

                                       12
<PAGE>   16

                                   ARTICLE 11
                                  MISCELLANEOUS

         SECTION 11.01. Ratification of Base Indenture; Fourth Supplemental
Indenture Controls. The Base Indenture, as supplemented by this Fourth
Supplemental Indenture, is in all respects ratified and confirmed, and this
Fourth Supplemental Indenture shall be deemed part of the Base Indenture in the
manner and to the extent herein and therein provided. The provisions of this
Fourth Supplemental Indenture shall supersede the provisions of the Base
Indenture to the extent the Base Indenture is inconsistent herewith.

         SECTION 11.02. Trustee Not Responsible for Recitals. The recitals
herein contained are made by the Company and not by the Trustee, and the Trustee
assumes no responsibility for the correctness thereof. The Trustee makes no
representation as to the validity or sufficiency of this Fourth Supplemental
Indenture.

         SECTION 11.03. Governing Law. This Fourth Supplemental Indenture and
each Subordinated Debenture shall be governed by and construed in accordance
with the laws of the State of New York, as applied to contracts made and
performed within the State of New York, without regard to its principles of
conflicts of laws.

         SECTION 11.04. References to Co-Chief Executive Officer. All references
in the Base Indenture to a Co-Chief Executive Officer of the Company shall mean
its Chief Executive Officer.

         SECTION 11.05. Severability. If any provision in the Base Indenture,
this Fourth Supplemental Indenture or in the Subordinated Debentures shall be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

         SECTION 11.06. Counterparts. The parties may sign any number of copies
of this Fourth Supplemental Indenture. Each signed copy shall be an original,
but all of them together represent the same agreement. Any signed copy shall be
sufficient proof of this Fourth Supplemental Indenture.

                                       13
<PAGE>   17

         IN WITNESS WHEREOF, the parties hereto have caused this Fourth
Supplemental Indenture to be duly executed as of the day and year first above
written.

                                        HERCULES INCORPORATED

                                        By  ___________________________________
                                            Name:
                                            Title:

                                        THE CHASE MANHATTAN BANK,
                                              as Trustee

                                        By  ___________________________________
                                            Name:
                                            Title:

                                       14
<PAGE>   18

                                                                     EXHIBIT A-1

                        [FORM OF SUBORDINATED DEBENTURE]

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS. NEITHER THIS
SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT
SUBJECT TO, REGISTRATION UNDER THE SECURITIES ACT AND ANY APPLICABLE STATE
SECURITIES LAWS.

THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES NOT TO OFFER, SELL
OR OTHERWISE TRANSFER SUCH SECURITY PRIOR TO THE DATE (THE "TRANSFER RESTRICTION
TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUE DATE
HEREOF AND THE LAST DATE ON WHICH HERCULES INCORPORATED OR ANY AFFILIATED PERSON
OF HERCULES INCORPORATED WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF
SUCH SECURITY) UNLESS SUCH OFFER, SALE OR OTHER TRANSFER IS (A) TO HERCULES
INCORPORATED OR ANY OF ITS SUBSIDIARIES, (B) PURSUANT TO A REGISTRATION
STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO
LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A, TO A
PERSON WHO IS OR WHO THE HOLDER REASONABLY BELIEVES IS A "QUALIFIED
INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT THAT
PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL
BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON
RULE 144A, (D) TO AN "ACCREDITED INVESTOR" (AS DEFINED IN RULE 501(a)(1), (2),
(3) OR (7) UNDER THE SECURITIES ACT) THAT IS AN INSTITUTIONAL INVESTOR, (E)
PURSUANT TO OFFERS AND SALES TO NON-U.S. PERSONS THAT OCCUR OUTSIDE THE UNITED
STATES WITHIN THE MEANING OF REGULATION S UNDER THE SECURITIES ACT OR (F)
PURSUANT TO ANY OTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF
THE SECURITIES ACT, SUBJECT TO THE RIGHT OF HERCULES INCORPORATED OR THE
TRANSFER AGENT FOR THE SECURITIES PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER
PURSUANT TO CLAUSES (D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF
COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM.
THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE THEN HOLDER OF THIS SECURITY
AFTER THE TRANSFER RESTRICTION TERMINATION DATE.

USE THE FOLLOWING IF THIS IS A GLOBAL SUBORDINATED DEBENTURE:

[THIS SUBORDINATED DEBENTURE IS A GLOBAL SUBORDINATED DEBENTURE WITHIN THE
MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME
OF THE DEPOSITORY TRUST COMPANY (THE "CLEARING AGENCY") OR A NOMINEE OF THE
CLEARING AGENCY. THIS SUBORDINATED DEBENTURE IS EXCHANGEABLE FOR SUBORDINATED
DEBENTURES REGISTERED IN THE NAME OF A PERSON OTHER THAN THE CLEARING AGENCY OR
ITS NOMINEE ONLY IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE AND NO
TRANSFER OF THIS SUBORDINATED DEBENTURE (OTHER THAN A TRANSFER OF THIS
SUBORDINATED DEBENTURE AS A WHOLE BY THE CLEARING AGENCY

                                      A1-1
<PAGE>   19

TO A NOMINEE OF THE CLEARING AGENCY OR BY A NOMINEE OF THE CLEARING AGENCY TO
THE CLEARING AGENCY OR ANOTHER NOMINEE OF THE CLEARING AGENCY) MAY BE REGISTERED
EXCEPT IN LIMITED CIRCUMSTANCES.

UNLESS THIS SUBORDINATED DEBENTURE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE
OF THE DEPOSITORY TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF TRANSFER,
EXCHANGE OR PAYMENT, AND ANY SUBORDINATED DEBENTURE ISSUED IS REGISTERED IN THE
NAME OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY AND ANY PAYMENT HEREON IS MADE TO CEDE & CO.,
ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY A PERSON IS
WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.]

                                      A1-2
<PAGE>   20

No.________                                               CUSIP NO. ____________

                              HERCULES INCORPORATED

                        FLOATING RATE JUNIOR SUBORDINATED
                     DEFERRABLE INTEREST DEBENTURE DUE 2000

                  Hercules Incorporated, a Delaware corporation (the "COMPANY",
which term includes any successor corporation under the Indenture hereinafter
referred to), for value received, hereby promises to pay the principal sum of
_________ Dollars ($ ) on December 29, 2000, or such other date as may be
provided pursuant to the terms of the Indenture.

         (a) Interest on the principal amount of this Subordinated Debenture
will accrue and be payable at a rate (the "INTEREST RATE") per annum, reset
quarterly, equal to LIBOR plus 2.45% of such principal amount. Notwithstanding
the foregoing, if the Company fails to pay principal or interest when due, such
overdue amount shall accrue interest, compounded quarterly, at the then
applicable periodic Interest Rate, but only to the extent permitted by
applicable law. The term "INTEREST", as used herein, includes any such
additional interest and Additional Interest unless otherwise stated.

         (b) Interest on this Subordinated Debenture will be payable quarterly
in arrears on March 29, 2000, June 29, 2000, September 29, 2000 and December 29,
2000, commencing March 29, 2000 (each an "INTEREST PAYMENT Date"), will accrue
from and including the most recent date to which interest has been paid or, if
no interest has been paid, from December 23, 1999, to but excluding the related
Interest Payment Date, except as otherwise described below. If additional
Subordinated Debentures are issued upon the issuance of additional Preferred
Securities and Common Securities as contemplated in Section 2.01, the Company
will establish the date on which interest will begin to accrue and the initial
Interest Payment Date with respect to such additional Subordinated Debentures.

         For the Subordinated Debentures issued on December 23, 1999, the
Interest Rate in effect for the period from and including December 23, 1999, to
but excluding March 29, 2000, shall be 8 5/8%. The Interest Rate in effect
thereafter shall be determined by the Calculation Agent on the Determination
Date prior to the applicable Interest Payment Date. The amount of interest
payable for any interest period shall be computed on the basis of the actual
number of days in such period and a year of 360 days. If an Interest Payment
Date is not a Business Day, then such Interest Payment Date will be postponed to
the next succeeding Business Day, except if such Business Day is in the next
succeeding calendar month, such Interest Payment Date will be the immediately
preceding Business Day.

         (c) Interest shall be paid to the Person in whose name such
Subordinated Debenture or any predecessor Subordinated Debenture is registered
on the books and records of the Company at the close of business on the Regular
Record Date for such interest installment,

                                      A1-3
<PAGE>   21

which shall be the fifteenth (15th) day of the month in which the applicable
Interest Payment Date falls (the "REGULAR RECORD DATE"). Notwithstanding the
foregoing, so long as the Holder of the Subordinated Debenture is the Property
Trustee, the payment of the principal of and interest on this Subordinated
Debenture will be made at such place and to such account as may be designated by
the Property Trustee.

         The indebtedness evidenced by this Subordinated Debenture is, to the
extent provided in the Indenture, subordinate and junior in right of payment to
the prior payment in full of all existing and future Senior Indebtedness, and
this Subordinated Debenture is issued subject to the provisions of the Indenture
with respect thereto. Each Holder of this Subordinated Debenture, by accepting
the same, (i) agrees to and shall be bound by such provisions, (ii) authorizes
and directs the Trustee on his or her behalf to take such action as may be
necessary or appropriate to acknowledge or effectuate the subordination so
provided and (iii) appoints the Trustee his or her attorney-in-fact for any and
all such purposes. Each Holder hereof, by his or her acceptance hereof, hereby
waives all notice of the acceptance of the subordination provisions contained
herein and in the Indenture by each holder of Senior Indebtedness, whether now
outstanding or hereafter incurred, and waives reliance by each such holder upon
said provisions.

         This Subordinated Debenture shall not be entitled to any benefit under
the Indenture hereinafter referred to, be valid or become obligatory for any
purpose until the Certificate of Authentication hereon shall have been signed by
or on behalf of the Trustee.

         The provisions of this Subordinated Debenture are continued on the
reverse side hereof and such continued provisions shall for all purposes have
the same effect as though fully set forth at this place.

                                      A1-4
<PAGE>   22

         IN WITNESS WHEREOF, the Company has caused this instrument to be
executed.

                                          HERCULES INCORPORATED

                                          By: _________________________________
                                              Name:
                                              Title

Attest:

By:_______________________________
   Name:
   Title:

                                      A1-5
<PAGE>   23

                     [FORM OF CERTIFICATE OF AUTHENTICATION]

                          CERTIFICATE OF AUTHENTICATION

This is one of the Subordinated Debentures of the series of Debentures described
in the within-mentioned Indenture.

Dated:

THE CHASE MANHATTAN BANK,
as Trustee                                  or as Authentication Agent

By _______________________________          By ________________________________
         Authorized Signatory                        Authorized Signatory

                                      A1-6
<PAGE>   24

                         [FORM OF REVERSE OF DEBENTURE]

         This Subordinated Debenture is one of a duly authorized series of
Debentures of the Company (herein sometimes referred to as the "DEBENTURES"),
specified in the Indenture, all issued or to be issued in one or more series
under and pursuant to a Junior Subordinated Debentures Indenture dated as of
November 12, 1998, duly executed and delivered between the Company and The Chase
Manhattan Bank, as Trustee (the "TRUSTEE"), as supplemented by the Fourth
Supplemental Indenture dated as of December 23, 1999, between the Company and
the Trustee (the Indenture as so supplemented, the "INDENTURE"), to which
Indenture and all indentures supplemental thereto reference is hereby made for a
description of the rights, limitations of rights, obligations, duties and
immunities thereunder of the Trustee, the Company and the Holders of the
Subordinated Debentures. By the terms of the Indenture, the Debentures are
issuable thereunder in series that may vary as to amount, date of maturity, rate
of interest and in other respects as provided in the Indenture. This series of
Debentures is limited in aggregate principal amount as specified in said Fourth
Supplemental Indenture and herein sometimes referred to as the "SUBORDINATED
DEBENTURES."

         In case an Event of Default, as defined in the Indenture, shall have
occurred and be continuing, the principal of all of the Subordinated Debentures
may be declared, and upon such declaration shall become, due and payable, in the
manner, with the effect and subject to the conditions provided in the Indenture.

         The Indenture contains provisions permitting the Company and the
Trustee, with the consent of the Holders of at least a majority in aggregate
principal amount of the Debentures of each series affected thereby then
outstanding (and, in the case of any series of Debentures held as assets of a
Trust and with respect to which a Dissolution Event has not theretofore
occurred, such consent of holders of the Preferred Securities and the Common
Securities of such Trust as may be required under the Trust Agreement), as
defined in the Indenture, to reduce the principal amount of such Debentures;
reduce the percentage of the principal amount of such Debentures the Holders of
which must consent to an amendment of the Indenture or a waiver; change (i) the
stated maturity of the principal of or the interest on such Debentures, or (ii)
the rate of interest (or the manner of calculation thereof) on such Debentures,
change adversely to the Holders the redemption, conversion or exchange
provisions applicable to such Debentures, if any; change the currency in respect
of which the payments on such Debentures are to be made; make any change in the
subordination provisions in Article 10 of the Indenture that adversely affects
the rights of the Holders of the Debentures or any change to any other section
thereof that adversely affects their rights; or change the direct action rights
of holders of Preferred Securities; provided that, in the case of the
outstanding Debentures of a series then held by a Trust, no such amendment shall
be made that adversely affects the holders of the Preferred Securities of that
Trust, and no waiver of any Event of Default with respect to the Debentures of
that series or compliance with any covenant under the Indenture shall be
effective, without the prior consent of the holders of at least a majority of
the aggregate liquidation amount of the outstanding Preferred Securities of that
Trust or the holder of each such Preferred Security, as applicable.

                                      A1-7
<PAGE>   25

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

         No reference herein to the Indenture and no provision of this
Subordinated Debenture or of the Indenture shall alter or impair the obligation
of the Company, which is absolute and unconditional, to pay the principal of and
interest on this Subordinated Debenture at the time and place and at the rate or
rates and in the currency herein prescribed.

         As provided in the Indenture and subject to certain limitations herein
and therein set forth, this Subordinated Debenture is transferable by the
registered Holder hereof on the Register of the Company, upon surrender of this
Subordinated Debenture for registration of transfer at the office or agency of
the Trustee in the City and State of New York accompanied by a written
instrument or instruments of transfer in form satisfactory to the Company or the
Trustee duly executed by the registered Holder hereof or his attorney duly
authorized in writing, and thereupon one or more new Subordinated Debentures of
authorized denominations and for the same aggregate principal amount and series
will be issued to the designated transferee or transferees. No service charge
will be made for any such transfer, but the Company may require payment of a sum
sufficient to cover any tax or other governmental charge payable in relation
thereto.

         Prior to due presentment for registration of transfer of this
Subordinated Debenture, the Company, the Trustee, any paying agent and the
Registrar may deem and treat the registered holder hereof as the absolute owner
hereof (whether or not this Subordinated Debenture shall be overdue and
notwithstanding any notice of ownership or writing hereon made by anyone other
than the Registrar) for the purpose of receiving payment of or on account of the
principal hereof and interest due hereon and for all other purposes, and neither
the Company nor the Trustee nor any paying agent nor any Registrar shall be
affected by any notice to the contrary.

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

         The Subordinated Debentures of this series are issuable only in
registered form without coupons in denominations of $1,000,000 and any integral
multiple of $100,000 in excess thereof. The Subordinated Debentures may be
transferred or exchanged only in minimum denominations of $1,000,000 and
integral multiples of $100,000 in excess thereof, and any attempted transfer,

                                      A1-8
<PAGE>   26

sale or other disposition of Subordinated Debentures in a denomination of less
than $1,000,000 shall be deemed void and of no legal effect whatsoever.

         All terms used in this Subordinated Debenture that are defined in the
Indenture shall have the meanings assigned to them in the Indenture.

         THE INDENTURE AND THE DEBENTURES SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO ITS
PRINCIPLES OF CONFLICTS OF LAWS.

                                      A1-9<PAGE>   1

                                                                     EXHIBIT 4-Z

                      AMENDED AND RESTATED TRUST AGREEMENT

                                HERCULES TRUST VI

                          Dated as of December 23, 1999

<PAGE>   2

                                TABLE OF CONTENTS

<TABLE>
<S>               <C>                                                                              <C>
                                    ARTICLE I
                         INTERPRETATION AND DEFINITIONS

SECTION 1.1       Definitions..................................................................     2

                                   ARTICLE II
                               TRUST INDENTURE ACT

SECTION 2.1       Trust Indenture Act; Application.............................................     8
SECTION 2.2       Lists of Holders of Securities...............................................     9
SECTION 2.3       Reports by the Property Trustee..............................................     9
SECTION 2.4       Periodic Reports to Property Trustee.........................................     9
SECTION 2.5       Evidence of Compliance with Conditions Precedent.............................     9
SECTION 2.6       Events of Default; Waiver....................................................    10
SECTION 2.7       Event of Default; Notice.....................................................    11

                                   ARTICLE III
                                  ORGANIZATION

SECTION 3.1       Name.........................................................................    12
SECTION 3.2       Office.......................................................................    12
SECTION 3.3       Purpose......................................................................    12
SECTION 3.4       Authority....................................................................    12
SECTION 3.5       Title to Property of the Trust...............................................    13
SECTION 3.6       Powers and Duties of the Administrative Trustees.............................    13
SECTION 3.7       Prohibition of Actions by the Trust and the Trustees.........................    15
SECTION 3.8       Powers and Duties of the Property Trustee....................................    16
SECTION 3.9       Certain Duties and Responsibilities of the Property Trustee..................    18
SECTION 3.10      Certain Rights of Property Trustee...........................................    20
SECTION 3.11      Delaware Trustee.............................................................    22
SECTION 3.12      Execution of Documents.......................................................    23
SECTION 3.13      Not Responsible for Recitals or Issuance of Securities.......................    23
SECTION 3.14      Duration of Trust............................................................    23
SECTION 3.15      Mergers......................................................................    23

                                   ARTICLE IV
                                     SPONSOR

SECTION 4.1       Sponsor's Purchase of Common Securities......................................    25
SECTION 4.2       Responsibilities of the Sponsor..............................................    26
SECTION 4.3       Right to Proceed.............................................................    26
</TABLE>

                                       i
<PAGE>   3

<TABLE>
<S>               <C>                                                                              <C>
                                    ARTICLE V
                                    TRUSTEES

SECTION 5.1       Number of Trustees; Appointment of Co-Trustee................................    26
SECTION 5.2       Delaware Trustee.............................................................    27
SECTION 5.3       Property Trustee; Eligibility................................................    27
SECTION 5.4       Certain Qualifications of Administrative Trustees and
                  Delaware Trustee Generally...................................................    28
SECTION 5.5       Administrative Trustees......................................................    28
SECTION 5.6       Delaware Trustee.............................................................    29
SECTION 5.7       Appointment, Removal and Resignation of Trustees.............................    29
SECTION 5.8       Vacancies among Trustees.....................................................    31
SECTION 5.9       Effect of Vacancies..........................................................    31
SECTION 5.10      Meetings.....................................................................    31
SECTION 5.11      Delegation of Power..........................................................    32
SECTION 5.12      Merger, Conversion, Consolidation or Succession to Business..................    32
SECTION 5.13      Compensation.................................................................    32

                                   ARTICLE VI
                                  DISTRIBUTIONS

SECTION 6.1       Distributions................................................................    33

                                   ARTICLE VII
                             ISSUANCE OF SECURITIES

SECTION 7.1       General Provisions Regarding Securities......................................    33
SECTION 7.2       Execution and Authentication.................................................    33
SECTION 7.3       Form and Dating..............................................................    34
SECTION 7.4       Registrar and Paying Agent...................................................    35
SECTION 7.5       Paying Agent to Hold Money in Trust..........................................    36
SECTION 7.6       Replacement Securities.......................................................    36
SECTION 7.7       Outstanding Preferred Securities.............................................    37
SECTION 7.8       Preferred Securities in Treasury.............................................    37
SECTION 7.9       Temporary Securities.........................................................    37
SECTION 7.10      Cancellation.................................................................    37
SECTION 7.11      CUSIP Numbers................................................................    38

                                  ARTICLE VIII
                              DISSOLUTION OF TRUST

SECTION 8.1       Dissolution of Trust.........................................................    38
</TABLE>

                                       ii
<PAGE>   4

<TABLE>
<S>               <C>                                                                              <C>
                                   ARTICLE IX
                              TRANSFER OF INTERESTS

SECTION 9.1       Transfer of Securities.......................................................    39
SECTION 9.2       Transfer Procedures and Restrictions.........................................    41
SECTION 9.3       Deemed Security Holders......................................................    44
SECTION 9.4       Book Entry Interests.........................................................    44
SECTION 9.5       Notices to Clearing Agency...................................................    45
SECTION 9.6       Appointment of Successor Clearing Agency.....................................    45

                                    ARTICLE X
                LIMITATION OF LIABILITY OF HOLDERS OF SECURITIES,
                               TRUSTEES OR OTHERS

SECTION 10.1      Liability....................................................................    45
SECTION 10.2      Exculpation..................................................................    46
SECTION 10.3      Fiduciary Duty...............................................................    46
SECTION 10.4      Indemnification..............................................................    47
SECTION 10.5      Outside Businesses...........................................................    49

                                   ARTICLE XI
                                   ACCOUNTING

SECTION 11.1      Fiscal Year..................................................................    50
SECTION 11.2      Certain Accounting Matters...................................................    50
SECTION 11.3      Banking......................................................................    51
SECTION 11.4      Withholding..................................................................    51

                                   ARTICLE XII
                             AMENDMENTS AND MEETINGS

SECTION 12.1      Amendments...................................................................    51
SECTION 12.2      Meetings of the Holders of Securities;
                  Action by Written Consent....................................................    53

                                  ARTICLE XIII
                       REPRESENTATIONS OF PROPERTY TRUSTEE
                              AND DELAWARE TRUSTEE

SECTION 13.1      Representations and Warranties of Property Trustee...........................    55
SECTION 13.2      Representations and Warranties of Delaware Trustee...........................    55
</TABLE>

                                      iii
<PAGE>   5

<TABLE>
<S>               <C>                                                                              <C>
                                   ARTICLE XIV
                                  MISCELLANEOUS

SECTION 14.1      Notices......................................................................    56
SECTION 14.2      Governing Law................................................................    58
SECTION 14.3      Intention of the Parties.....................................................    58
SECTION 14.4      Headings.....................................................................    58
SECTION 14.5      Successors and Assigns.......................................................    58
SECTION 14.6      Partial Enforceability.......................................................    58
SECTION 14.7      Counterparts.................................................................    58

ANNEX I           Terms of Preferred Securities and Common Securities...............  I-1
EXHIBIT A-1       Form of Preferred Security Certificate............................  A1-1
EXHIBIT A-2       Form of Common Security Certificate...............................  A2-1
EXHIBIT B         Specimen Debenture................................................  B-1
EXHIBIT C         Purchase Agreement................................................  C-1
</TABLE>

                                       iv
<PAGE>   6

                             CROSS-REFERENCE TABLE*

<TABLE>
<CAPTION>
         Section of
         Trust Indenture Act                                                            Section of
         of 1939, as amended                                                            Agreement
         -------------------                                                            ---------
<S>                                                                                     <C>
         310(a).................................................................        5.3(a)
         310(b).................................................................        5.3(c)
         310(c).................................................................  Inapplicable

         311(a) and (b).........................................................        5.3(c)
         311(c).................................................................  Inapplicable

         312(a).................................................................        2.2(a)
         312(b).................................................................        2.2(b)
         313....................................................................        2.3
         314(a).................................................................        2.4
         314(b).................................................................  Inapplicable

         314(c).................................................................        2.5
         314(d).................................................................  Inapplicable

         314(e).................................................................        1.1, 2.5
         314(f).................................................................  Inapplicable

         315(a).................................................................        3.9(b)
         315(b).................................................................        2.7(a)
         315(c).................................................................        3.9(a)
         315(d).................................................................        3.9(b)
         316(a) and (b).........................................................        2.6 and
                                                                                        Annex I
         316(c).................................................................        3.6(f)
         317(a).................................................................        3.8(h)
         317(b).................................................................        3.8(i)
         ---------------
</TABLE>

         *This Cross-Reference Table does not constitute part of the Agreement
           and shall not affect the interpretation of any of its terms or
           provisions.

                                       i
<PAGE>   7

                              AMENDED AND RESTATED
                                 TRUST AGREEMENT
                                       OF
                                HERCULES TRUST VI

                  AMENDED AND RESTATED TRUST AGREEMENT (the "Agreement") dated
and effective as of December 23, 1999 by the Trustees (as defined herein), the
Sponsor (as defined herein) and by the holders, from time to time, of undivided
beneficial interests in the assets of the Trust (as defined herein) to be issued
pursuant to this Agreement;

                  WHEREAS, the Trustees and the Sponsor established Hercules
Trust VI (the "Trust"), a trust created under the Business Trust Act (as defined
herein) pursuant to a Trust Agreement dated as of December 21, 1999 (the
"Original Agreement"), and a Certificate of Trust filed with the Secretary of
State of the State of Delaware on December 21, 1999, for the sole purpose of
issuing and selling certain securities representing undivided beneficial
interests in the assets of the Trust and investing the proceeds thereof in
certain Debentures of the Debenture Issuer (each as hereinafter defined) and
engaging in only those activities necessary, advisable or incidental thereto;

                  WHEREAS, the parties hereto desire to amend and restate each
and every term and provision of the Original Agreement; and

                  NOW, THEREFORE, it being the intention of the parties hereto
that the Trust continue as a business trust under the Business Trust Act, that
the Original Agreement be amended and restated in its entirety as provided
herein and that this Agreement constitute the governing instrument of such
business trust, the Trustees declare that all assets contributed to the Trust
will be held in trust for the benefit of the holders, from time to time, of the
securities representing undivided beneficial interests in the assets of the
Trust issued hereunder, subject to the provisions of this Agreement and, in
consideration of the mutual covenants contained herein and other good and
valuable consideration, the receipt of which is hereby acknowledged, the
parties, intending to be legally bound hereby, agree as follows:

<PAGE>   8

                                   ARTICLE I
                         INTERPRETATION AND DEFINITIONS

SECTION 1.1       Definitions.

                  Unless the context otherwise requires:

                  (a) capitalized terms used in this Agreement but not defined
         in the preamble above or elsewhere herein have the respective meanings
         assigned to them in this Section 1.1;

                  (b) a term defined anywhere in this Agreement has the same
         meaning throughout;

                  (c) all references to "the Agreement" or "this Agreement" are
         to this Agreement and each Annex and Exhibit hereto, as modified,
         supplemented or amended from time to time;

                  (d) all references in this Agreement to Articles and Sections
         and Annexes and Exhibits are to Articles and Sections of and Annexes
         and Exhibits to this Agreement unless otherwise specified;

                  (e) a term defined in the Trust Indenture Act (as defined
         herein) has the same meaning when used in this Agreement unless
         otherwise defined in this Agreement or unless the context otherwise
         requires; and

                  (f) a reference to the singular includes the plural and vice
         versa.

                  "Administrative Trustee" has the meaning set forth in Section
5.1.

                  "Affiliate" has the same meaning as given to that term in Rule
405 under the Securities Act or any successor rule thereunder.

                  "Agent" means any Paying Agent or Registrar.

                  "Agreement" means this Amended and Restated Trust Agreement,
dated as of December 23, 1999, including Annex I and all the exhibits hereto.

                  "Authorized Officer" of a Person means any other Person that
is authorized to legally bind such former Person.

                  "Book Entry Interest" means a beneficial interest in a Global
Preferred Security Certificate registered in the name of a Clearing Agency or
its nominee, ownership and transfers of which shall be maintained and made
through book entries by a Clearing Agency as described in Section 9.4.

                                       2
<PAGE>   9

                  "Business Day" means any day other than a Saturday, Sunday or
other day on which banking institutions in The City of New York or Wilmington,
Delaware are authorized or required by law, regulation or executive order to
close; provided, however, that, with respect to LIBOR distribution
determinations, calculations and payments, such day is also a London Business
Day.

                  "Business Trust Act" means Chapter 38 of Title 12 of the
Delaware Code, 12 Del. Code Section 3801 et seq., as it may be amended from time
to time, or any successor legislation.

                  "Calculation Agent" means The Chase Manhattan Bank or any
successor.

                  "Clearing Agency" means an organization registered as a
"Clearing Agency" pursuant to Section 17A of the Exchange Act that is acting as
depositary for the Preferred Securities and in whose name or in the name of a
nominee of that organization shall be registered a global certificate and which
shall undertake to effect book-entry transfers and pledges of the Preferred
Securities.

                  "Closing Time" means the Closing Time as defined in the
Purchase Agreement.

                  "Code" means the Internal Revenue Code of 1986, as amended
from time to time, or any successor legislation.

                  "Commission" means the United States Securities and Exchange
Commission as from time to time constituted, or if at any time after the
execution of this Agreement such Commission is not existing and performing the
duties now assigned to it under applicable federal securities laws, then the
body performing such duties at such time.

                  "Common Securities" has the meaning specified in Section
7.1(a).

                  "Common Securities Guarantee" means the Common Securities
Guarantee Agreement, dated as of December 23, 1999 of the Sponsor in respect of
the Common Securities.

                  "Company Indemnified Person" means (a) any Administrative
Trustee; (b) any Affiliate of any Administrative Trustee; (c) any officers,
directors, shareholders, members, partners, employees, representatives or agents
of any Administrative Trustee; or (d) any officer, employee or agent of the
Trust or its Affiliates; provided that the term "Company Indemnified Person"
shall not include any Fiduciary Indemnified Person.

                  "Corporate Trust Office" means the office of the Property
Trustee for the conduct of corporate trust business at which matters related to
this Agreement shall, at any particular time, be principally administered, which
office at the date of execution of this Agreement is located at c/o Chase
Manhattan Trust Company, National Association, One Liberty Place, 52nd Floor,
1650 Market Street, Philadelphia, Pennsylvania 19103, Attention: Capital Markets
Fiduciary Services.

                  "Covered Person" means: (a) any officer, director,
shareholder, partner, member, representative, employee or agent of (i) the Trust
or (ii) the Trust's Affiliates; and (b) any Holder of Securities.

                                       3
<PAGE>   10

                  "Debenture Issuer" means Hercules Incorporated, a Delaware
corporation, or any successor entity resulting from any consolidation,
amalgamation, merger or other business combination, in its capacity as issuer of
the Debentures under the Indenture.

                  "Debentures" means the Floating Rate Junior Subordinated
Deferrable Interest Debentures due 2000 of the Debenture Issuer issued pursuant
to the Indenture.

                  "Debenture Trustee" means The Chase Manhattan Bank, a New York
banking corporation, as trustee under the Indenture until a successor is
appointed thereunder, and thereafter means such successor trustee.

                  "Default" means an event, act or condition that with notice of
lapse of time, or both, would constitute an Event of Default.

                  "Definitive Preferred Securities" has the meaning set forth in
Section 7.3.

                  "Delaware Trustee" has the meaning set forth in Section 5.2.

                  "Direct Action" has the meaning set forth in Section 3.8(e).

                  "Distribution" means a distribution payable to Holders of
Securities in accordance with Section 6.1.

                  "DTC" means The Depository Trust Company, the initial Clearing
Agency.

                  "Event of Default" means, with respect to the Securities, an
Event of Default (as defined in the Indenture) that has occurred and is
continuing in respect of the Debentures.

                  "Exchange Act" means the Securities Exchange Act of 1934, as
amended from time to time, or any successor legislation.

                  "Fiduciary Indemnified Person" has the meaning set forth in
Section 10.4(b).

                  "Fiscal Year" has the meaning set forth in Section 11.1.

                  "Global Preferred Security" has the meaning set forth in
Section 7.3.

                  "Holder" means a Person in whose name a Security or Successor
Security is registered, such Person being a beneficial owner within the meaning
of the Business Trust Act.

                  "Indemnified Person" means a Company Indemnified Person or a
Fiduciary Indemnified Person.

                  "Indenture" means the Junior Subordinated Debentures
Indenture, dated as of November 12, 1998, between the Debenture Issuer and the
Debenture Trustee relating to the Debenture Issuer's junior subordinated
debentures, as supplemented by the Fourth Supplemental Indenture thereto, dated
as of December 23, 1999, and, as further amended or supplemented from time to
time.

                                       4
<PAGE>   11

                  "Investment Company" means an investment company as defined in
the Investment Company Act.

                  "Investment Company Act" means the Investment Company Act of
1940, as amended from time to time, or any successor legislation.

                  "Investment Company Event" means that the Trust has received
an opinion of counsel experienced in such matters to the effect that, as a
result of the occurrence of a change in law or regulation or a change in
interpretation or application of law or regulation by any legislative body,
court, governmental agency or regulatory authority, there is more than an
insubstantial risk that the Trust is or will be considered an "investment
company" under the Investment Company Act that is required to be registered
under this law, which change becomes effective on or after March 12, 1999.

                  "Legal Action" has the meaning set forth in Section 3.6(h).

                  "LIBOR" has the meaning set forth in Section 2 of Annex I
hereto.

                  "Like Amount" has the meaning set forth in Section 3 of Annex
I hereto.

                  "Liquidation Amount" has the meaning set forth in Section 2 of
Annex I hereto.

                  "List of Holders" has the meaning set forth in Section 2.2(a)
of Annex I hereto.

                  "London Business Day" means any day other than a Saturday or
Sunday on which banks are open for business (including dealings in deposits in
U.S. dollars) in London.

                  "Majority in Liquidation Amount" means, with respect to the
Securities, except as provided in the terms of the Preferred Securities or by
the Trust Indenture Act, Holders of outstanding Securities voting together as a
single class or, as the context may require, Holders of outstanding Preferred
Securities or Holders of outstanding Common Securities voting separately as a
class, who are the record owners of more than 50% of the aggregate Liquidation
Amount (including the amount that would be paid on redemption, liquidation or
otherwise, plus accumulated and unpaid Distributions to the date upon which the
voting percentages are determined) of all outstanding Securities of the relevant
class.

                  "Officers' Certificate" means, with respect to any Person, a
certificate signed by the Chief Executive Officer, the Chief Financial Officer,
the President or a Vice President, and by the Treasurer, an Assistant Treasurer,
the Secretary or an Assistant Secretary. Any Officers' Certificate delivered by
the Trust shall be signed by at least one Administrative Trustee. Any Officers'
Certificate delivered with respect to compliance with a condition or covenant
provided for in this Agreement shall include:

                  (a) a statement that each officer signing the Officers'
         Certificate has read the covenant or condition and the definitions
         relating thereto;

                  (b) a brief statement of the nature and scope of the
         examination or investigation undertaken by each officer in rendering
         the Officers' Certificate;

                                       5
<PAGE>   12

                  (c) a statement that each such officer has made such
         examination or investigation as, in such officer's opinion, is
         necessary to enable such officer to express an informed opinion as to
         whether or not such covenant or condition has been complied with; and

                  (d) a statement as to whether, in the opinion of each such
         officer, such condition or covenant has been complied with.

                  "Opinion of Counsel" means a written opinion of counsel, who
may be an employee of the Sponsor, and who shall be reasonably acceptable to the
Property Trustee, provided, that the General Counsel or Assistant General
Counsel of the Sponsor shall be deemed to be reasonably acceptable to the
Trustee.

                  "Participants"  has the meaning specified in Section 7.3(a).

                  "Paying Agent" has the meaning specified in Section 7.4.

                  "Payment Amount" has the meaning specified in Section 6.1.

                  "Person" means a legal person, including any individual,
corporation, estate, partnership, joint venture, association, joint stock
company, limited liability company, trust, unincorporated association, or
government or any agency or political subdivision thereof, or any other entity
of whatever nature.

                  "PORTAL Market" means the Private Offerings, Resales and
Trading through Automated Linkages Market operated by the National Association
of Securities Dealers, Inc. or any successor thereto.

                  "Preferred Securities" has the meaning specified in Section
7.1(a).

                  "Preferred Securities Guarantee" means the Preferred
Securities Guarantee Agreement dated as of December 23, 1999 of the Sponsor in
respect of the Preferred Securities.

                  "Preferred Security Beneficial Owner" means, with respect to a
Book Entry Interest, a Person who is the beneficial owner of such Book-Entry
Interest, as reflected on the books of the Clearing Agency, or on the books of a
Person maintaining an account with such Clearing Agency (directly as a Clearing
Agency Participant or as an indirect participant, in each case in accordance
with the rules of such Clearing Agency).

                  "Property Trustee" has the meaning set forth in Section
5.3(a).

                  "Property Trustee Account" has the meaning set forth in
Section 3.8(c).

                  "Purchase Agreement" means the Purchase Agreement for the
offering and sale of Preferred Securities in the form of Exhibit C.

                  "QIB" means a qualified institutional buyer as defined in Rule
144A.

                                       6
<PAGE>   13

                  "Quorum" means a majority of the Administrative Trustees or,
if there are only two Administrative Trustees, both of them.

                  "Registrar" has the meaning set forth in Section 7.4.

                  "Related Party" means, with respect to the Sponsor, any direct
or indirect wholly owned subsidiary of the Sponsor or any other Person that
owns, directly or indirectly, 100% of the outstanding voting securities of the
Sponsor.

                  "Responsible Officer" means, with respect to the Property
Trustee, any officer within the Corporate Trust Office of the Property Trustee
with direct responsibility for the administration of this Agreement, including
any vice-president, any assistant vice-president, any assistant secretary, any
assistant treasurer or other officer of the Corporate Trust Office of the
Property Trustee customarily performing functions similar to those performed by
any of the above designated officers and also means, with respect to a
particular corporate trust matter, any other officer of the Property Trustee to
whom such matter is referred because of that officer's knowledge of and
familiarity with the particular subject.

                  "Restricted Security" has the meaning set forth in Section
9.1.

                  "Rule 144A" means Rule 144A as promulgated under the
Securities Act, or any successor rule.

                  "Rule 144(k)" means Rule 144(k) as promulgated under the
Securities Act, or any successor rule.

                  "Securities" or "Trust Securities" means the Common Securities
and the Preferred Securities.

                  "Securities Act" means the Securities Act of 1933, as amended
from time to time, or any successor legislation.

                  "Securities Guarantees" means the Common Securities Guarantee
and the Preferred Securities Guarantee.

                  "Sponsor" means Hercules Incorporated, a Delaware corporation,
or any successor entity resulting from any merger, consolidation, amalgamation
or other business combination, in its capacity as sponsor of the Trust.

                  "Successor Delaware Trustee" has the meaning set forth in
Section 5.7(b)(ii).

                  "Successor Entity" has the meaning set forth in Section
3.15(b)(i).

                  "Successor Property Trustee" has the meaning set forth in
Section 3.8(f)(ii).

                  "Successor Securities" has the meaning set forth in Section
3.15(b)(i)(B).

                  "Super Majority" has the meaning set forth in Section
2.6(a)(ii).

                                       7
<PAGE>   14

                  "10% in Liquidation Amount" means, with respect to the
Securities, except as provided in the terms of the Preferred Securities or by
the Trust Indenture Act, Holders of outstanding Securities voting together as a
single class or, as the context may require, Holders of outstanding Preferred
Securities or Holders of outstanding Common Securities voting separately as a
class, who are the record owners of 10% or more of the aggregate Liquidation
Amount (including the amount that would be paid on redemption, liquidation or
otherwise, plus accumulated and unpaid Distributions to the date upon which the
voting percentages are determined) of all outstanding Securities of the relevant
class.

                  "Transfer Restriction Termination Date" means the first date
on which the Preferred Securities (other than Preferred Securities acquired by
the Trust or any Affiliate thereof) may be sold pursuant to Rule 144(k).

                  "Treasury Regulations" means the income tax regulations,
including temporary and proposed regulations, promulgated under the Code by the
United States Treasury, as such regulations may be amended from time to time
(including corresponding provisions of succeeding regulations).

                  "Trustee" or "Trustees" means each Person who has signed this
Agreement as a trustee, so long as such Person shall continue as Trustee of the
Trust in accordance with the terms hereof, and all other Persons who may from
time to time be duly appointed, qualified and serving as Trustees in accordance
with the provisions hereof, and references herein to a Trustee or the Trustees
shall refer to such Person or Persons solely in their capacity as trustees
hereunder.

                  "Trust Indenture Act" means the Trust Indenture Act of 1939,
as amended from time to time, or any successor legislation.

                                   ARTICLE II
                               TRUST INDENTURE ACT

SECTION 2.1       Trust Indenture Act; Application.

         (a) This Agreement is subject to the provisions of the Trust Indenture
Act that are required to be part of this Agreement in order for this Agreement
to be qualified under the Trust Indenture Act and shall, to the extent
applicable, be governed by such provisions.

         (b) The Property Trustee shall be the only Trustee which is a trustee
for the purposes of the Trust Indenture Act.

         (c) If and to the extent that any provision of this Agreement limits,
qualifies or conflicts with the duties imposed by Sections 310 to 317,
inclusive, of the Trust Indenture Act, such imposed duties shall control.

         (d) The application of the Trust Indenture Act to this Agreement shall
not affect the nature of the Securities as equity securities representing
undivided beneficial interests in the assets of the Trust.

                                       8
<PAGE>   15

SECTION 2.2       Lists of Holders of Securities.

         (a) Each of the Sponsor and the Administrative Trustees on behalf of
the Trust shall provide the Property Trustee, unless the Property Trustee is the
Registrar for the Securities, (i) within 14 days after each record date for
payment of Distributions, a list, in such form as the Property Trustee may
reasonably require, of the names and addresses of the Holders of the Securities
("List of Holders") as of such record date, provided that neither the Sponsor
nor the Administrative Trustees on behalf of the Trust shall be obligated to
provide such List of Holders at any time the List of Holders does not differ
from the most recent List of Holders given to the Property Trustee by the
Sponsor and the Administrative Trustees on behalf of the Trust, and (ii) at any
other time, within 30 days of receipt by the Trust of a written request for a
List of Holders as of a date no more than 14 days before such List of Holders is
given to the Property Trustee. The Property Trustee shall preserve, in as
current a form as is reasonably practicable, all information contained in Lists
of Holders given to it or which it receives in the capacity as Paying Agent (if
acting in such capacity), provided that the Property Trustee may destroy any
List of Holders previously given to it on receipt of a new List of Holders.

         (b) The Property Trustee shall comply with the obligations set forth
under Sections 311(a), 311(b) and 312(b) of the Trust Indenture Act.

SECTION 2.3       Reports by the Property Trustee.

                  Within 60 days after September 1 of each year, commencing
September 1, 2000, the Property Trustee shall provide to the Holders of the
Preferred Securities such reports as are required by Section 313 of the Trust
Indenture Act, if any, in the form and in the manner provided by Section 313 of
the Trust Indenture Act. The Property Trustee shall also comply with the
requirements of Section 313(d) of the Trust Indenture Act.

SECTION 2.4       Periodic Reports to Property Trustee.

                  Each of the Sponsor and the Administrative Trustees on behalf
of the Trust shall provide to the Property Trustee such documents, reports and
information as are required by Section 314 of the Trust Indenture Act (if any)
and the compliance certificate required by Section 314 of the Trust Indenture
Act in the form, in the manner and at the times required by Section 314 of the
Trust Indenture Act.

SECTION 2.5       Evidence of Compliance with Conditions Precedent.

                  Each of the Sponsor and the Administrative Trustees on behalf
of the Trust shall provide to the Property Trustee such evidence of compliance
with any conditions precedent provided for in this Agreement that relate to any
of the matters set forth in Section 314(c) of the Trust Indenture Act. Any
certificate or opinion required to be given by an officer pursuant to Section
314(c)(1) of the Trust Indenture Act may be given in the form of an Officers'
Certificate.

                                       9
<PAGE>   16

SECTION 2.6       Events of Default; Waiver.

         (a) The Holders of a Majority in Liquidation Amount of Preferred
Securities may, by vote, on behalf of the Holders of all of the Preferred
Securities, waive any past Event of Default in respect of the Preferred
Securities and its consequences, provided that, if the underlying Event of
Default under the Indenture:

                  (i) is not waivable under the Indenture, the Event of Default
         under the Agreement shall also not be waivable; or

                  (ii) requires the consent or vote of greater than a majority
         in aggregate principal amount of the holders of the Debentures (a
         "Super Majority") to be waived under the Indenture, the Event of
         Default under the Agreement may only be waived by the vote of the
         Holders of at least the proportion in aggregate Liquidation Amount of
         the Preferred Securities that the relevant Super Majority represents of
         the aggregate principal amount of the Debentures outstanding.

The foregoing provisions of this Section 2.6(a) shall be in lieu of Section
316(a)(1)(B) of the Trust Indenture Act and such Section 316(a)(1)(B) of the
Trust Indenture Act is hereby expressly excluded from this Agreement and the
Securities, as permitted by the Trust Indenture Act. Upon such waiver, any such
default shall cease to exist, and any Event of Default with respect to the
Preferred Securities arising therefrom shall be deemed to have been cured, for
every purpose of this Agreement, but no such waiver shall extend to any
subsequent or other default or an Event of Default with respect to the Preferred
Securities or impair any right consequent thereon. Any waiver by the Holders of
the Preferred Securities of an Event of Default with respect to the Preferred
Securities shall also be deemed to constitute a waiver by the Holders of the
Common Securities of any such Event of Default with respect to the Common
Securities for all purposes of this Agreement without any further act, vote, or
consent of the Holders of the Common Securities.

         (b) The Holders of a Majority in Liquidation Amount of the Common
Securities may, by vote, on behalf of the Holders of all of the Common
Securities, waive any past Event of Default with respect to the Common
Securities and its consequences, provided that, if the underlying Event of
Default under the Indenture:

                  (i) is not waivable under the Indenture (except where the
         Holders of the Common Securities are deemed to have waived such Event
         of Default under the Agreement as provided below in this Section
         2.6(b)), the Event of Default under the Agreement shall also not be
         waivable; or

                  (ii) requires the consent or vote of a Super Majority to be
         waived, except where the Holders of the Common Securities are deemed to
         have waived such Event of Default under the Agreement as provided below
         in this Section 2.6(b), the Event of Default under the Agreement may
         only be waived by the vote of the Holders of at least the proportion in
         aggregate Liquidation Amount of the Common Securities that the relevant
         Super Majority represents of the aggregate principal amount of the
         Debentures outstanding;

                                       10
<PAGE>   17

provided further, each Holder of Common Securities will be deemed to have waived
any such Event of Default and all Events of Default with respect to the Common
Securities and its consequences until all Events of Default with respect to the
Preferred Securities have been cured, waived or otherwise eliminated, and until
such Events of Default have been so cured, waived or otherwise eliminated, the
Property Trustee will be deemed to be acting solely on behalf of the Holders of
the Preferred Securities and only the Holders of the Preferred Securities will
have the right to direct the Property Trustee in accordance with the terms of
the Securities. The foregoing provisions of this Section 2.6(b) shall be in lieu
of Sections 316(a)(1)(A) and 316(a)(1)(B) of the Trust Indenture Act and such
Sections 316(a)(1)(A) and 316(a)(1)(B) of the Trust Indenture Act are hereby
expressly excluded from this Agreement and the Securities, as permitted by the
Trust Indenture Act. Subject to the foregoing provisions of this Section 2.6(b),
upon such waiver, any such default shall cease to exist and any Event of Default
with respect to the Common Securities arising therefrom shall be deemed to have
been cured for every purpose of this Agreement, but no such waiver shall extend
to any subsequent or other default or Event of Default with respect to the
Common Securities or impair any right consequent thereon.

         (c) A waiver of an Event of Default under the Indenture by the Property
Trustee, at the direction of the Holders of the Preferred Securities,
constitutes a waiver of the corresponding Event of Default under this Agreement.
The foregoing provisions of this Section 2.6(c) shall be in lieu of Section
316(a)(1)(B) of the Trust Indenture Act and such Section 316(a)(1)(B) of the
Trust Indenture Act is hereby expressly excluded from this Agreement and the
Securities, as permitted by the Trust Indenture Act.

SECTION 2.7       Event of Default; Notice.

         (a) The Property Trustee shall, within 90 days after the occurrence of
any default with respect to the Securities, transmit by mail, first class
postage prepaid, to the Holders of the Securities and to the Sponsor, notices of
all such defaults actually known to a Responsible Officer of the Property
Trustee, unless such defaults have been cured before the giving of such notice
(the term "defaults" for the purposes of this Section 2.7(a) being hereby
defined to be a Default as defined in the Indenture, not including any periods
of grace provided for therein and irrespective of the giving of any notice
provided therein); provided that, except for a default in the payment of
principal of (or premium, if any) or interest on any of the Debentures, the
Property Trustee shall be protected in withholding such notice if and so long as
a committee of Responsible Officers of the Property Trustee in good faith
determines that the withholding of such notice is in the interests of the
Holders of the Securities.

         (b) The Property Trustee shall not be deemed to have actual knowledge
of any default except:

                  (i) a default under Sections 6.01(a) and 6.01(b) of the
         Indenture; or

                  (ii) any default as to which the Property Trustee shall have
         received written notice or of which a Responsible Officer of the
         Property Trustee charged with the administration of the Agreement shall
         have actual knowledge.

                                       11
<PAGE>   18

         (c) Within ten Business Days after the occurrence of any Event of
Default actually known to a Responsible Officer of the Property Trustee, the
Property Trustee shall transmit notice of such Event of Default to the Holders
of the Preferred Securities, the Administrative Trustees and the Sponsor, unless
such Event of Default shall have been cured, waived or otherwise eliminated. The
Sponsor and the Administrative Trustees shall file annually with the Property
Trustee a certification as to whether or not they are in compliance with all the
conditions and covenants applicable to them under this Agreement.

                                  ARTICLE III
                                  ORGANIZATION

SECTION 3.1       Name.

         The Trust is named "Hercules Trust VI" as such name may be modified
from time to time by the Administrative Trustees following written notice to the
Delaware Trustee, the Property Trustee and the Holders of Securities. The
Trust's activities may be conducted under the name of the Trust or any other
name deemed advisable by the Administrative Trustees.

SECTION 3.2       Office.

         The address of the principal office of the Trust is c/o Hercules Plaza,
1313 North Market Street, Wilmington, Delaware 19894-0001. On ten Business Days'
prior written notice to the Delaware Trustee, the Property Trustee and the
Holders of Securities, the Administrative Trustees may designate another
principal office.

SECTION 3.3       Purpose.

         The exclusive purposes and functions of the Trust are (a) to issue and
sell Securities, (b) use the proceeds from the sale of the Securities to acquire
the Debentures in an aggregate principal amount equal to the aggregate
Liquidation Amount of such Securities, and (c) except as otherwise limited
herein, to engage in only those other activities necessary, advisable or
incidental thereto, including without limitation, those activities specified in
Sections 3.6, 3.8, 3.9, 3.10, 3.11 and/or 3.12.

SECTION 3.4       Authority.

         Subject to the limitations provided in this Agreement and to the
specific duties of the Property Trustee, the Administrative Trustees shall have
exclusive and complete authority to carry out the purposes of the Trust. An
action taken by one or more of the Administrative Trustees in accordance with
their powers shall constitute the act of and serve to bind the Trust and an
action taken by the Property Trustee on behalf of the Trust in accordance with
its powers shall constitute the act of and serve to bind the Trust. In dealing
with the Trustees acting on behalf of the Trust, no Person shall be required to
inquire into the authority of the Trustees to bind the Trust. Persons dealing
with the Trust are entitled to rely conclusively on the power and authority of
the Trustees as set forth in this Agreement.

                                       12
<PAGE>   19

SECTION 3.5       Title to Property of the Trust.

         Except as provided in Section 3.8 with respect to the Debentures and
the Property Trustee Account or as otherwise provided in this Agreement, legal
title to all assets of the Trust shall be vested in the Trust. The Holders shall
not have legal title to any part of the assets of the Trust, but shall have an
undivided beneficial interest in the assets of the Trust.

SECTION 3.6       Powers and Duties of the Administrative Trustees.

                  The Administrative Trustees shall have the exclusive power
(subject to Section 4.2), duty and authority, and are hereby authorized and
directed, to cause the Trust to engage in the following activities:

         (a) to execute, deliver, issue and sell the Preferred Securities and
the Common Securities in accordance with this Agreement; provided, however, that
(i) the Trust may issue no more than one series of Preferred Securities and no
more than one series of Common Securities, (ii) there shall be no interests in
the Trust other than the Securities, and (iii) the issuance of Securities shall
be limited to a simultaneous issuance of both Preferred Securities and Common
Securities at the Closing Time, subject to (1) the issuance of additional
Securities in the event of transfers, exchanges and replacements and (2) the
right of the Trust to issue additional Securities, without the consent of any
Holders, with the same terms as the applicable Securities (other than the date
of issuance and the date on which Distributions begin to accumulate) so as to
form the same series with such Securities;

         (b) in connection with the issue and sale of the Preferred Securities,
at the direction of the Sponsor, to:

                  (i) execute and file any documents prepared by the Sponsor, or
         take any acts as determined by the Sponsor to be necessary in order to
         qualify or register all or part of the Preferred Securities in any
         State in which the Sponsor has determined to qualify or register such
         Preferred Securities for sale;

                  (ii) execute and file an application, prepared by the Sponsor,
         to qualify the Preferred Securities for trading in the PORTAL Market;

                  (iii) execute and deliver letters, documents, or instruments
         with DTC and other Clearing Agencies relating to the Preferred
         Securities; and

                  (iv) execute and file any agreement, certificate or other
         document which such Administrative Trustee deems necessary or
         appropriate in connection with the issuance and sale of the Preferred
         Securities;

         (c) to acquire the Debentures with the proceeds of the sale of the
Preferred Securities and the Common Securities; provided, however, that the
Administrative Trustees shall cause legal title to the Debentures to be held of
record in the name of the Property Trustee for the benefit of the Holders of the
Preferred Securities and the Holders of Common Securities;

                                       13
<PAGE>   20

         (d) if requested by the Sponsor, to cause the Trust to enter into and
to execute and deliver on behalf of the Trust such agreements (including the
Purchase Agreement) and arrangements as may be necessary or desirable in
connection with the sale of Preferred Securities to the initial purchaser(s)
thereof and the consummation thereof, and to take all action, and exercise all
discretion, as may be necessary or desirable in connection with the consummation
thereof;

         (e) to give the Sponsor and the Property Trustee prompt written notice
of the occurrence of any event specified in Section 8.1;

         (f) to establish a record date with respect to all actions to be taken
hereunder that require a record date be established, including and with respect
to, for the purposes of Section 316(c) of the Trust Indenture Act,
Distributions, voting rights and redemptions, and to issue relevant notices to
the Holders of Preferred Securities and Holders of Common Securities as to such
actions and applicable record dates;

         (g) to take all actions and perform such duties as may be required of
the Administrative Trustees pursuant to the terms of the Securities;

         (h) to bring or defend, pay, collect, compromise, arbitrate, resort to
legal action, or otherwise adjust claims or demands of or against the Trust
("Legal Action"), unless pursuant to Section 3.8(e), the Property Trustee has
the exclusive power to bring such Legal Action;

         (i) to employ or otherwise engage employees and agents (who may be
designated as officers with titles) and managers, contractors, advisors, and
consultants and pay reasonable compensation for such services;

         (j) to cause the Trust to comply with the Trust's obligations under the
Trust Indenture Act;

         (k) to give the certificate required by Section 314(a)(4) of the Trust
Indenture Act to the Property Trustee, which certificate may be executed by any
Administrative Trustee;

         (l) to incur expenses that are necessary or incidental to carry out any
of the purposes of the Trust;

         (m) to act as, or appoint another Person to act as, Registrar for the
Securities or to appoint a Paying Agent for the Securities as provided in
Section 7.4 except for such time as such power to appoint a Paying Agent is
vested in the Property Trustee;

         (n) to give prompt written notice to the Property Trustee and to
Holders of the Securities of any notice received from the Debenture Issuer of
its election to defer payments of interest on the Debentures by extending the
interest payment period under the Indenture;

         (o) to take all action that may be necessary or appropriate for the
preservation and the continuation of the Trust's valid existence, rights,
franchises and privileges as a statutory business trust under the laws of the
State of Delaware and of each other jurisdiction in which

                                       14
<PAGE>   21

such existence is necessary to protect the limited liability of the Holders of
the Preferred Securities or to enable the Trust to effect the purposes for which
the Trust was created;

         (p) to take any action (provided that such action does not materially
adversely affect the interests of Holders), not inconsistent with this Agreement
or with applicable law, that the Administrative Trustees determine in their
discretion to be necessary or desirable in carrying out the activities of the
Trust as set out in this Section 3.6, including, but not limited to:

                  (i) causing the Trust not to be deemed to be an Investment
         Company required to be registered under the Investment Company Act;

                  (ii) causing the Trust to be classified for United States
         Federal income tax purposes as a grantor trust; and

                  (iii) cooperating with the Debenture Issuer to ensure that the
         Debentures will be treated as indebtedness of the Debenture Issuer for
         United States Federal income tax purposes;

         (q) to take all action necessary to cause all applicable tax returns
and tax information reports that are required to be filed with respect to the
Trust to be duly prepared and filed by the Administrative Trustees, on behalf of
the Trust; and

         (r) to execute and deliver and record, file or register, as applicable,
all documents, certificates, agreements or instruments, perform all duties and
powers, and do all things for and on behalf of the Trust in all matters
necessary, advisable or incidental to the foregoing.

         The Administrative Trustees must exercise the powers set forth in this
Section 3.6 in a manner that is consistent with the purposes and functions of
the Trust set out in Section 3.3, and the Administrative Trustees shall not take
any action that is inconsistent with the purposes and functions of the Trust set
forth in Section 3.3.

         Subject to this Section 3.6, the Administrative Trustees shall have
none of the powers or the authority of the Property Trustee set forth in Section
3.8.

         Any expenses incurred by the Administrative Trustees pursuant to this
Section 3.6 shall be reimbursed by the Debenture Issuer.

SECTION 3.7       Prohibition of Actions by the Trust and the Trustees.

         (a) The Trust and the Trustees (including the Property Trustee and the
Delaware Trustee) shall not, and the Administrative Trustees shall cause the
Trust not to, engage in any activity other than as required or authorized by
this Agreement. In particular, the Trust shall not:

                  (i) invest any proceeds received by the Trust from holding the
         Debentures, but shall distribute all such proceeds to Holders of
         Securities pursuant to the terms of this Agreement and of the
         Securities;

                  (ii) acquire any assets other than as expressly provided
         herein;

                                       15
<PAGE>   22

                  (iii) possess Trust property for other than a Trust purpose or
         execute any mortgage in respect of, or pledge, any Trust property;

                  (iv) make any loans or incur any indebtedness other than loans
         represented by the Debentures;

                  (v) possess any power or otherwise act in such a way as to
         vary the Trust assets or the terms of the Securities in any way
         whatsoever;

                  (vi) issue any securities or other evidences of beneficial
         ownership of, or beneficial interest in, the Trust other than the
         Securities;

                  (vii) so long as any Debentures are held by the Property
         Trustee, the Trustees shall not (A) direct the time, method and place
         of conducting any proceeding with respect to any remedy available to
         the Debenture Trustee, or exercise any trust or power conferred upon
         the Debenture Trustee with respect to the Debentures, (B) waive any
         past default that is waivable under the Indenture, (C) exercise any
         right to rescind or annul a declaration of acceleration of the maturity
         of the principal of the Debentures, or (D) consent to any amendment,
         modification or termination of the Indenture or the Debentures where
         such consent shall be required, without, in each case, obtaining (1)
         the prior approval of the Holders of a Majority in Liquidation Amount
         of all outstanding Securities; provided, however, that where a consent
         under the Indenture would require the consent of each holder of
         Debentures affected thereby, no such consent shall be given by the
         Property Trustee without the prior approval of each Holder of
         Securities and (2) an Opinion of Counsel delivered to the Trust from
         tax counsel experienced in such matters to the effect that the Trust
         will not be classified as an association taxable as a corporation for
         United States Federal income tax purposes on account of such action;

                  (viii) revoke any action previously authorized or approved by
         a vote of the Holders of Preferred Securities except by subsequent vote
         of such Holders;

                  (ix) revoke any action previously authorized or approved by a
         vote of the Holders of Common Securities except by subsequent vote of
         such Holders; or

                  (x) undertake (or permit to be undertaken) any activity that
         would cause the Trust not to be classified for United States Federal
         income tax purposes as a grantor trust.

SECTION 3.8       Powers and Duties of the Property Trustee.

         (a) The legal title to the Debentures shall be owned by and held of
record in the name of the Property Trustee in trust for the benefit of the Trust
and the Holders of the Securities. The right, title and interest of the Property
Trustee to the Debentures shall vest automatically in each Person who may
hereafter be appointed as Property Trustee in accordance with Section 5.7. Such
vesting and cessation of title shall be effective whether or not conveyancing
documents with regard to the Debentures have been executed and delivered.

                                       16
<PAGE>   23

         (b) The Property Trustee shall not transfer its right, title and
interest in the Debentures to the Administrative Trustees or to the Delaware
Trustee (if the Property Trustee does not also act as Delaware Trustee).

         (c) The Property Trustee shall:

                  (i) establish and maintain a segregated non-interest bearing
         trust account (the "Property Trustee Account") in the name of and under
         the exclusive control of the Property Trustee on behalf of the Holders
         of the Securities and, upon the receipt of payments of funds made in
         respect of the Debentures held by the Property Trustee, deposit such
         funds into the Property Trustee Account and make payments or cause the
         Paying Agent to make payments to the Holders of the Preferred
         Securities and Holders of the Common Securities from the Property
         Trustee Account in accordance with Section 6.1; and funds in the
         Property Trustee Account shall be held uninvested until disbursed in
         accordance with this Agreement;

                  (ii) engage in such ministerial activities as shall be
         necessary or appropriate to effect the redemption of the Preferred
         Securities and the Common Securities when the Debentures mature;

                  (iii) upon written notice of distribution issued by the
         Administrative Trustees in accordance with the terms of the Securities,
         engage in such ministerial activities as shall be necessary or
         appropriate to effect the distribution of the Debentures to Holders of
         Securities upon the occurrence of certain events; and

                  (iv) take such ministerial action as may be requested by the
         Administrative Trustees in connection with the winding up of the
         affairs of or liquidation of the Trust in accordance with this
         Agreement and the preparation, execution and filing of a certificate of
         cancellation or other appropriate certificates with the Secretary of
         State of the State of Delaware and other appropriate governmental
         authorities.

         (d) The Property Trustee shall take all actions and perform such duties
as may be specifically required of the Property Trustee pursuant to the terms of
this Agreement and the Securities.

         (e) Subject to Section 3.9, the Property Trustee shall take any Legal
Action which arises out of or in connection with an Event of Default of which a
Responsible Officer of the Property Trustee has actual knowledge or the Property
Trustee's duties and obligations under this Agreement or the Trust Indenture Act
and, if the Property Trustee shall have failed to take such Legal Action, the
Holders of the Preferred Securities in at least an aggregate Liquidation Amount
equal to the specified percentage of Holders of Debentures entitled to take such
Legal Action may, to the fullest extent permitted by law, take such Legal Action
without first proceeding against the Property Trustee or the Trust; provided
however, that if an Event of Default has occurred and is continuing and such
event is attributable to the failure of the Debenture Issuer to pay the
principal of or premium, if any, or interest on the Debentures on the date such
principal, premium, if any, or interest is otherwise payable (or in the case of
redemption, on the redemption date), then a Holder of Preferred Securities may
directly institute

                                       17
<PAGE>   24

a proceeding for enforcement of payment to such Holder of the principal of or
premium, if any, or interest on the Debentures having a principal amount equal
to the aggregate Liquidation Amount of the Preferred Securities of such Holder
on or after the respective due date specified in the Debentures (a "Direct
Action"). Except as provided in the preceding sentence, the Holders of Preferred
Securities will not be able to exercise directly any other remedy available to
the holders of the Debentures.

         (f) The Property Trustee shall continue to serve as a Trustee until
either:

                  (i) the Trust has been completely liquidated and the proceeds
         of the liquidation distributed to the Holders of Securities pursuant to
         the terms of the Securities and this Agreement; or

                  (ii) a successor Property Trustee has been appointed and has
         accepted that appointment in accordance with Section 5.7 (a "Successor
         Property Trustee").

         (g) The Property Trustee shall have the legal power to exercise all of
the rights, powers and privileges of a holder of Debentures under the Indenture
and, if an Event of Default actually known to a Responsible Officer of the
Property Trustee occurs and is continuing, the Property Trustee shall, for the
benefit of Holders of the Securities, enforce its rights as holder of the
Debentures subject to the rights of the Holders pursuant to the terms of the
Securities and this Agreement.

         (h) The Property Trustee shall be authorized to undertake any actions
set forth in Section 317(a) of the Trust Indenture Act.

         (i) For such time as the Property Trustee is the Paying Agent, the
Property Trustee may authorize one or more Persons to act as additional Paying
Agents and to pay Distributions, redemption payments or liquidation payments on
behalf of the Trust with respect to all Securities and any such Paying Agent
shall comply with Section 317(b) of the Trust Indenture Act. Any such additional
Paying Agent may be removed by the Property Trustee at any time the Property
Trustee remains as Paying Agent and a successor Paying Agent or additional
Paying Agents may be (but are not required to be) appointed at any time by the
Property Trustee while the Property Trustee is acting as Paying Agent.

         (j) Subject to this Section 3.8, the Property Trustee shall have none
of the duties, liabilities, powers or the authority of the Administrative
Trustees set forth in Section 3.6.

         Notwithstanding anything expressed or implied to the contrary in this
Agreement or any Annex or Exhibit hereto, the Property Trustee must exercise the
powers set forth in this Section 3.8 in a manner that is consistent with the
purposes and functions of the Trust set out in Section 3.3.

SECTION 3.9 Certain Duties and Responsibilities of the Property Trustee.

         (a) The Property Trustee, before the occurrence of any Event of Default
and after the curing or waiving of all Events of Default that may have occurred,
shall undertake to perform

                                       18
<PAGE>   25

only such duties as are specifically set forth in this Agreement and in the
Securities and no implied covenants or obligations shall be read into this
Agreement against the Property Trustee. In case an Event of Default has occurred
(that has not been cured or waived pursuant to Section 2.6) of which a
Responsible Officer of the Property Trustee has actual knowledge, the Property
Trustee shall exercise such of the rights and powers vested in it by this
Agreement, and use the same degree of care and skill in their exercise, as a
prudent person would exercise or use under the circumstances in the conduct of
his or her own affairs.

         (b) No provision of this Agreement shall be construed to relieve the
Property Trustee from liability for its own negligent action, its own negligent
failure to act, its own bad faith or its own willful misconduct, except that:

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

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

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

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

                  (iii) the Property Trustee shall not be liable with respect to
         any action taken or omitted to be taken by it in good faith in
         accordance with the direction of the Holders of a Majority in
         Liquidation Amount of the Securities relating to the time, method and
         place of conducting any proceeding for any remedy available to the
         Property Trustee, or exercising any trust or power conferred upon the
         Property Trustee under this Agreement;

                  (iv) no provision of this Agreement shall require the Property
         Trustee to expend or risk its own funds or otherwise incur personal
         financial liability in the performance of any of its duties or in the
         exercise of any of its rights or powers, if it shall have reasonable
         grounds for believing that the repayment of such funds or liability is
         not reasonably

                                       19
<PAGE>   26

         assured to it under the terms of this Agreement or indemnity reasonably
         satisfactory to the Property Trustee against such risk or liability is
         not reasonably assured to it;

                  (v) the Property Trustee's sole duty with respect to the
         custody, safekeeping and physical preservation of the Debentures and
         the Property Trustee Account shall be to deal with such property in a
         similar manner as the Property Trustee deals with similar property for
         its own account, subject to the protections and limitations on
         liability afforded to the Property Trustee under this Agreement and the
         Trust Indenture Act;

                  (vi) the Property Trustee shall have no duty or liability for
         or with respect to the value, genuineness, existence or sufficiency of
         the Debentures or the payment of any taxes or assessments levied
         thereon or in connection therewith;

                  (vii) the Property Trustee shall not be liable for any
         interest on any money received by it except as it may otherwise agree
         in writing with the Sponsor. Money held by the Property Trustee need
         not be segregated from other funds held by it except in relation to the
         Property Trustee Account maintained by the Property Trustee pursuant to
         Section 3.8(c)(i) and except to the extent otherwise required by law;
         and

                  (viii) the Property Trustee shall not be responsible for
         monitoring the compliance by the Administrative Trustees or the Sponsor
         with their respective duties under this Agreement, nor shall the
         Property Trustee be liable for any default or misconduct of the
         Administrative Trustees or the Sponsor.

SECTION 3.10      Certain Rights of Property Trustee.

         (a) Subject to the provisions of Section 3.9:

                  (i) the Property Trustee may conclusively rely and shall be
         fully protected in acting or refraining from acting upon any
         resolution, certificate, statement, instrument, opinion, report,
         notice, request, direction, consent, order, bond, debenture, note,
         other evidence of indebtedness or other paper or document believed by
         it to be genuine and to have been signed, sent or presented by the
         proper party or parties;

                  (ii) any direction or act of the Sponsor or the Administrative
         Trustees contemplated by this Agreement may be sufficiently evidenced
         by an Officers' Certificate;

                  (iii) whenever in the administration of this Agreement, the
         Property Trustee shall deem it desirable that a matter be proved or
         established before taking, suffering or omitting any action hereunder,
         the Property Trustee (unless other evidence is herein specifically
         prescribed) may, in the absence of bad faith on its part, request and
         conclusively rely upon an Officers' Certificate which, upon receipt of
         such request, shall be promptly delivered by the Sponsor or the
         Administrative Trustees;

                                       20
<PAGE>   27

                  (iv) the Property Trustee shall have no duty to see to any
         recording, filing or registration of any instrument (including any
         financing or continuation statement or any filing under tax or
         securities laws) or any re-recording, refiling or registration thereof;

                  (v) the Property Trustee may consult with counsel or other
         experts of its selection and the advice or opinion of such counsel and
         experts with respect to legal matters or advice within the scope of
         such experts' area of expertise shall be full and complete
         authorization and protection in respect of any action taken, suffered
         or omitted by it hereunder in good faith and in accordance with such
         advice or opinion, such counsel may be counsel to the Sponsor or any of
         its Affiliates, and may include any of its employees; and the Property
         Trustee shall have the right at any time to seek instructions
         concerning the administration of this Agreement from any court of
         competent jurisdiction;

                  (vi) the Property Trustee shall be under no obligation to
         exercise any of the rights or powers vested in it by this Agreement at
         the request or direction of any Holder, unless such Holder shall have
         provided to the Property Trustee security and indemnity, reasonably
         satisfactory to the Property Trustee, against the costs, expenses
         (including reasonable attorneys' fees and expenses and the expenses of
         the Property Trustee's agents, nominees or custodians) and liabilities
         that might be incurred by it in complying with such request or
         direction, including such reasonable advances as may be requested by
         the Property Trustee in respect of the time, method or place of
         conducting any proceeding for any remedy available to the Property
         Trustee or the exercise of any trust or power conferred on the Property
         Trustee under this Agreement;

                  (vii) the Property Trustee shall not be bound to make any
         investigation into the facts or matters stated in any resolution,
         certificate, statement, instrument, opinion, report, notice, request,
         direction, consent, order, bond, debenture, note, other evidence of
         indebtedness or other paper or document, but the Property Trustee, in
         its discretion, may make such further inquiry or investigation into
         such facts or matters as it may see fit;

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

                  (ix) any action taken by the Property Trustee or its agents
         hereunder shall bind the Trust and the Holders of the Securities, and
         the signature of the Property Trustee or its agents alone shall be
         sufficient and effective to perform any such action and no third party
         shall be required to inquire as to the authority of the Property
         Trustee to so act or as to its compliance with any of the terms and
         provisions of this Agreement, both of which shall be conclusively
         evidenced by the Property Trustee's or its agent's taking such action;

                  (x) whenever in the administration of this Agreement the
         Property Trustee shall deem it desirable to receive instructions with
         respect to enforcing any remedy or right or

                                       21
<PAGE>   28

         taking any other action hereunder, the Property Trustee (i) may request
         instructions from the Holders of the Securities which instructions may
         only be given by the Holders of the same proportion in Liquidation
         Amount of the Securities as would be entitled to direct the Property
         Trustee under the terms of the Securities in respect of such remedy,
         right or action, (ii) may refrain from enforcing such remedy or right
         or taking such other action until such instructions are received, and
         (iii) shall be protected in conclusively relying on, or acting in
         accordance with, such instructions;

                  (xi) except as otherwise expressly provided by this Agreement,
         the Property Trustee shall not be under any obligation to take any
         action that is discretionary under the provisions of this Agreement;
         and

                  (xii) the Property Trustee shall not be liable for any action
         taken, suffered, or omitted to be taken by it in good faith, without
         negligence, and reasonably believed by it to be authorized or within
         the discretion or rights or powers conferred upon it by this Agreement.

         (b) No provision of this Agreement shall be deemed to impose any duty
or obligation on the Property Trustee to perform any act or acts or exercise any
right, power, duty or obligation conferred or imposed on it, in any jurisdiction
in which it shall be illegal, or in which the Property Trustee shall be
unqualified or incompetent in accordance with applicable law, to perform any
such act or acts, or to exercise any such right, power, duty or obligation. No
permissive power or authority available to the Property Trustee shall be
construed to be a duty.

         (c) It is expressly understood and agreed by the parties hereto that in
fulfilling its obligations as Property Trustee hereunder on behalf of the Trust,
(i) any agreements or instruments executed or delivered by The Chase Manhattan
Bank are executed and delivered not in its individual capacity but solely as
Property Trustee under this Agreement in the exercise of the powers and
authority conferred and vested in it, (ii) each of the representations,
undertakings and agreements herein made on the part of the Trust is made and
intended not as representations, warranties, covenants, undertakings and
agreements by The Chase Manhattan Bank in its individual capacity but is made
and intended for the purpose of binding only the Trust, and (iii) under no
circumstances (except with respect to funds delivered to it relating to payments
in respect of the Securities) shall The Chase Manhattan Bank in its individual
capacity be personally liable for the payment of any indebtedness or expenses of
the Trust or be liable for the breach or failure of any obligation,
representation, warranty or covenant made or undertaken by the Trust under this
Agreement except if such breach or failure is due to any negligence, bad faith
or willful misconduct of the Property Trustee.

SECTION 3.11      Delaware Trustee.

         (a) Notwithstanding any other provision of this Agreement other than
Section 5.2, the Delaware Trustee shall not be entitled to exercise any powers,
nor shall the Delaware Trustee have any of the duties and responsibilities of
the Administrative Trustees or the Property Trustee described in this Agreement
(except as required under the Business Trust Act). Except as set

                                       22
<PAGE>   29

forth in Section 5.2, the Delaware Trustee shall be a Trustee for the sole and
limited purpose of fulfilling the requirements of Section 3807 of the Business
Trust Act.

         (b) It is expressly understood and agreed by the parties hereto that in
fulfilling its obligations as Delaware Trustee hereunder on behalf of the Trust,
(i) any agreements or instruments executed or delivered by Chase Manhattan Bank
Delaware are executed and delivered not in its individual capacity but solely as
Delaware Trustee under this Agreement in the exercise of the powers and
authority conferred and vested in it, (ii) each of the representations,
undertakings and agreements herein made on the part of the Trust is made and
intended not as representations, warranties, covenants, undertakings and
agreements by Chase Manhattan Bank Delaware in its individual capacity but is
made and intended for the purpose of binding only the Trust, and (iii) under no
circumstances shall Chase Manhattan Bank Delaware in its individual capacity be
personally liable for the payment of any indebtedness or expenses of the Trust
or be liable for the breach or failure of any obligation, representation,
warranty, or covenant made or undertaken by the Trust under this Agreement
except if such breach or failure is due to any negligence, bad faith or willful
misconduct of the Delaware Trustee.

SECTION 3.12      Execution of Documents.

         Except as otherwise required by the Business Trust Act or applicable
law, each Administrative Trustee, individually, is authorized to execute and
deliver on behalf of the Trust any documents, agreements, instruments or
certificates that the Administrative Trustees have the power and authority to
execute and deliver pursuant to this Agreement.

SECTION 3.13 Not Responsible for Recitals or Issuance of Securities.

         The recitals contained in this Agreement and the Securities shall be
taken as the statements of the Sponsor, and the Trustees do not assume any
responsibility for their correctness. The Trustees make no representations as to
the value or condition of the property of the Trust or any part thereof. The
Trustees make no representations as to the validity or sufficiency of this
Agreement or the Securities.

SECTION 3.14      Duration of Trust.

         The Trust, unless dissolved pursuant to the provisions of Article VIII
hereof, shall have existence until December 29, 2001.

SECTION 3.15      Mergers.

         (a) The Trust may not merge with or into, convert into, consolidate,
amalgamate, or be replaced by, or convey, transfer or lease its properties and
assets as an entirety or substantially as an entirety to any Person, except as
described in Section 3.15(b) and (c) and except with respect to the distribution
of all Debentures to Holders of Securities pursuant to Section 8.1(a)(iii).

                                       23
<PAGE>   30

         (b) The Trust may, at the request of the Sponsor, with the consent of
the Administrative Trustees or, if there are more than two, a majority of the
Administrative Trustees and without the consent of the Holders of the
Securities, the Delaware Trustee or the Property Trustee, merge with or into,
convert into, consolidate, amalgamate, or be replaced by, or convey, transfer or
lease its properties and assets as an entirety or substantially as an entirety
to, a trust organized as such under the laws of any State; provided that:

                  (i) such successor entity (the "Successor Entity") either:

                           (A) expressly assumes all of the obligations of the
                  Trust under the Securities; or

                           (B) substitutes for the Securities other securities
                  having substantially the same terms as the Securities (the
                  "Successor Securities") so long as the Successor Securities
                  rank the same as the Securities rank with respect to
                  Distributions and payments upon liquidation, redemption and
                  otherwise;

                  (ii) the Sponsor expressly appoints a trustee of the Successor
         Entity that possesses the same powers and duties as the Property
         Trustee with respect to the Debentures;

                  (iii) the Successor Securities (excluding any securities
         substituted for any Common Securities) are listed, quoted or included
         for trading, or any Successor Securities will be listed, quoted or
         included for trading, upon notification of issuance, on any national
         securities exchange or with any other organization on which the
         Preferred Securities are then listed, quoted or included;

                  (iv) such merger, conversion, consolidation, amalgamation,
         replacement, conveyance, transfer or lease does not cause the Preferred
         Securities (including any Successor Securities) or the Debentures to be
         downgraded or placed under surveillance or review by any nationally
         recognized statistical rating organization that publishes a rating on
         the Preferred Securities or the Debentures;

                  (v) such merger, conversion, consolidation, amalgamation,
         replacement, conveyance, transfer or lease does not adversely affect
         the rights, preferences and privileges of the Holders of the Securities
         (including the holders of any Successor Securities) in any material
         respect (other than with respect to any dilution of the interests of
         such Holders or holders, as the case may be, in the Successor Entity);

                  (vi) the Successor Entity has a purpose substantially
         identical to that of the Trust;

                  (vii) prior to such merger, conversion, consolidation,
         amalgamation, replacement, conveyance, transfer or lease, the Sponsor
         has received an opinion of a nationally recognized independent counsel
         to the Trust experienced in such matters to the effect that:

                                       24
<PAGE>   31

                           (A) such merger, conversion, consolidation,
                  amalgamation, replacement, conveyance, transfer or lease does
                  not adversely affect the rights, preferences and privileges of
                  the Holders of the Securities (including the holders of any
                  Successor Securities) in any material respect (other than with
                  respect to any dilution of the interests of such Holders or
                  holders, as the case may be, in the Successor Entity); and

                           (B) following such merger, conversion, consolidation,
                  amalgamation, replacement, conveyance, transfer or lease,
                  neither the Trust nor the Successor Entity, if any, will be
                  required to register as an Investment Company; and

                  (viii) the Sponsor or any permitted successor or assignee owns
         all of the common securities of the Successor Entity and guarantees the
         obligations of the Successor Entity under the Successor Securities at
         least to the extent provided by the Preferred Securities Guarantee and
         the Common Securities Guarantee.

         (c) Notwithstanding Section 3.15(b), the Trust shall not, except with
the consent of Holders of 100% in Liquidation Amount of the Securities, merge
with or into, convert into, consolidate, amalgamate, or be replaced by, or
convey, transfer or lease its properties and assets as an entirety or
substantially as an entirety to, any other Person or permit any other Person to
merge with or into, consolidate, amalgamate, or replace it if such merger,
conversion, consolidation, amalgamation, replacement, conveyance, transfer or
lease would cause the Trust or the Successor Entity, if any, not to be
classified as a grantor trust for United States Federal income tax purposes.

                                   ARTICLE IV
                                     SPONSOR

SECTION 4.1       Sponsor's Purchase of Common Securities.

         At the Closing Time, the Sponsor will purchase all of the Common
Securities then issued by the Trust, in an amount equal to at least 3% of the
total capital of the Trust, at the same time as the Preferred Securities are
issued and sold. The aggregate Liquidation Amount of Common Securities at any
time shall not be less than 3% of the total capital of the Trust.

         For so long as the Preferred Securities remain outstanding, the Sponsor
covenants (i) to maintain, directly or indirectly, 100% ownership of the Common
Securities; provided, however, that any permitted successor of the Sponsor under
the Indenture may succeed to the Sponsor's interest in the Common Securities,
(ii) to use its best efforts to cause the Trust (a) to remain a business trust,
except in connection with a distribution of Debentures to the Holders of
Securities in liquidation of the Trust, the redemption of all the Securities, or
certain mergers, consolidations or amalgamations, each as permitted by this
Agreement, and not to voluntarily dissolve, wind up, liquidate or be terminated,
except as permitted by this Agreement, and (b) to otherwise continue to be
classified as a grantor trust for United States federal income tax purposes,
(iii) to use its best efforts to ensure that the Trust shall not be an
Investment Company for purposes of the Investment Company Act, (iv) to use its
best efforts to cause each Holder of

                                       25
<PAGE>   32

Securities to be treated as owning an undivided beneficial interest in the
Debentures and (v) to take no action which would cause the dissolution,
liquidation or winding up of the Trust, except as otherwise provided in this
Agreement.

SECTION 4.2       Responsibilities of the Sponsor.

         In connection with the issue and sale of the Preferred Securities, the
Sponsor shall have the exclusive right (subject to Section 3.6) and
responsibility to engage in the following activities:

         (a) to determine the jurisdictions in which to take appropriate action
to qualify or register for sale all or part of the Preferred Securities and to
do any and all such acts, other than actions which must be taken by the Trust,
and advise the Trust of actions it must take, and prepare for execution and
filing any documents to be executed and filed by the Trust, as the Sponsor deems
necessary or advisable in order to comply with the applicable laws of any such
jurisdictions;

         (b) to prepare, execute and file on behalf of the Trust an application
to the PORTAL Market;

         (c) to prepare, execute and file on behalf of the Trust documents or
instruments to be delivered to the Clearing Agency relating to the Preferred
Securities; and

         (d) to negotiate the terms of, execute, enter into and deliver the
Purchase Agreement providing for the sale of the Preferred Securities.

SECTION 4.3       Right to Proceed.

         The Sponsor acknowledges the rights of the Holders of Preferred
Securities to bring one or more Direct Actions under the circumstances specified
in this Agreement.

                                   ARTICLE V
                                    TRUSTEES

SECTION 5.1       Number of Trustees; Appointment of Co-Trustee.

         The number of Trustees initially shall be five (5), and:

         (a) at any time before the issuance of any Securities, the Sponsor may,
by written instrument, increase or decrease the number of Trustees; and

         (b) after the issuance of any Securities, the number of Trustees may be
increased or decreased by vote of the Holders of a Majority in Liquidation
Amount of the Common Securities voting as a class at a meeting of the Holders of
the Common Securities;

provided, however, that, the number of Trustees shall in no event be less than
two (2); provided further that (1) one Trustee shall be a Person meeting the
requirements of Section 5.2 (the

                                       26
<PAGE>   33

"Delaware Trustee"); (2) there shall be at least one Trustee who is an employee
or officer of, or is affiliated with the Sponsor (an "Administrative Trustee");
and (3) one Trustee shall be the Property Trustee, and such Trustee may also
serve as Delaware Trustee if it meets the applicable requirements.
Notwithstanding the above, unless an Event of Default shall have occurred and be
continuing, at any time or times, for the purpose of meeting the legal
requirements of the Trust Indenture Act or of any jurisdiction in which any part
of the Trust's property may at the time be located, the Holders of a Majority in
Liquidation Amount of the Common Securities acting as a class at a meeting of
the Holders of the Common Securities, and the Administrative Trustees shall have
power to appoint one or more Persons either to act as a co-trustee, jointly with
the Property Trustee, of all or any part of the Trust's property, or to act as
separate trustee of any such property, in either case with such powers as may be
provided in the instrument of appointment, and to vest in such Person or Persons
in such capacity any property, title, right or power deemed necessary or
desirable, subject to the provisions of this Agreement. In case an Event of
Default has occurred and is continuing, the Property Trustee alone shall have
power to make any such appointment of a co-trustee.

SECTION 5.2       Delaware Trustee.

         For so long as required by the Business Trust Act, the Delaware Trustee
shall be:

         (a) a natural person who is a resident of the State of Delaware; or

         (b) if not a natural person, an entity which has its principal place of
business in the State of Delaware, and otherwise meets the requirements of
applicable law, provided, however, if the Property Trustee has its principal
place of business in the State of Delaware and otherwise meets the requirements
of applicable law, then the Property Trustee shall also be the Delaware Trustee
and Section 3.11 shall have no application.

SECTION 5.3       Property Trustee; Eligibility.

         (a) There shall at all times be one Trustee (the "Property Trustee")
which shall act as Property Trustee and which shall:

                  (i) not be an Affiliate of the Sponsor; and

                  (ii) be a corporation organized and doing business under the
         laws of the United States of America or any State or Territory thereof
         or of the District of Columbia, or a corporation or Person permitted by
         the Commission to act as an indenture trustee under the Trust Indenture
         Act, authorized under such laws to exercise corporate trust powers,
         having a combined capital and surplus of at least $50,000,000, and
         subject to supervision or examination by federal, state, territorial or
         District of Columbia authority. If such corporation publishes reports
         of condition at least annually, pursuant to law or to the requirements
         of the supervising or examining authority referred to above, then for
         the purposes of this Section 5.3(a)(ii), the combined capital and
         surplus of such corporation shall be deemed to be its combined capital
         and surplus as set forth in its most recent report of condition so
         published.

                                       27
<PAGE>   34

         (b) If at any time the Property Trustee shall cease to be eligible to
so act under Section 5.3(a), the Property Trustee shall immediately resign in
the manner and with the effect set forth in Section 5.7(c).

         (c) If the Property Trustee has or shall acquire any "conflicting
interest" within the meaning of Section 310(b) of the Trust Indenture Act, the
Property Trustee and the Holder of the Common Securities (as if it were the
obligor referred to in Section 310(b) of the Trust Indenture Act) shall in all
respects comply with the provisions of Section 310(b) of the Trust Indenture
Act.

         (d) The Preferred Securities Guarantee shall be deemed to be
specifically described in this Agreement for purposes of clause (i) of the first
provision contained in Section 310(b) of the Trust Indenture Act.

         (e) The initial Property Trustee shall be:

                      The Chase Manhattan Bank
                      c/o Chase Manhattan Trust Company, National Association
                      One Liberty Place, 52nd Floor
                      1650 Market Street
                      Philadelphia, Pennsylvania 19103
                      Attention:    Capital Markets Fiduciary Services
                      Telephone: (215) 988-1317
                      Telecopier: (215) 972-8372

SECTION 5.4       Certain Qualifications of Administrative Trustees and Delaware
                  Trustee Generally.

         Each Administrative Trustee and the Delaware Trustee (unless the
Property Trustee also acts as Delaware Trustee) shall be either a natural person
who is at least 21 years of age or a legal entity that shall act through one or
more Authorized Officers.

SECTION 5.5       Administrative Trustees.

                           The initial Administrative Trustees shall be:

                           Israel J. Floyd
                           Michael J. Scott
                           Stuart C. Shears

                           c/o Hercules Incorporated
                           Hercules Plaza
                           1313 North Market Street
                           Wilmington, Delaware 19894-0001
                           Telephone:  (302) 594-5000
                           Telecopier:  (302) 594-5210

                                       28
<PAGE>   35

         (a) Except as expressly set forth in this Agreement and except if a
meeting of the Administrative Trustees is called with respect to any matter over
which the Administrative Trustees have power to act, any power of the
Administrative Trustees may be exercised by, or with the consent of, any one
such Administrative Trustee.

         (b) Unless otherwise determined by the Administrative Trustees, and
except as otherwise required by the Business Trust Act or applicable law, any
Administrative Trustee acting alone is authorized to execute on behalf of the
Trust any documents which the Administrative Trustees have the power and
authority to cause the Trust to execute pursuant to Section 3.6.

SECTION 5.6       Delaware Trustee.

                  The initial Delaware Trustee shall be:

                  Chase Manhattan Bank Delaware
                  1201 Market Street
                  Wilmington, Delaware 19801
                  Attention:  Corporate Trust Department
                  Telephone:  (302) 984-3372
                  Telecopier:  (302) 428-4903

SECTION 5.7       Appointment, Removal and Resignation of Trustees.

         (a) Subject to Section 5.7(b), Trustees may be appointed or removed
without cause at any time:

                  (i) until the issuance of any Securities, by written
         instrument executed by the Sponsor;

                  (ii) unless an Event of Default shall have occurred and be
         continuing after the issuance of any Securities, by vote of the Holders
         of a Majority in Liquidation Amount of the Common Securities voting as
         a class at a meeting of the Holders of the Common Securities; and

                  (iii) if an Event of Default shall have occurred and be
         continuing after the issuance of the Securities, with respect to the
         Property Trustee or the Delaware Trustee, by vote of Holders of a
         Majority in Liquidation Amount of the Preferred Securities voting as a
         class at a meeting of Holders of the Preferred Securities (it being
         understood that in no event will the Holders of the Preferred
         Securities have the right to vote, appoint, remove or replace the
         Administrative Trustees, which voting rights are exclusively vested in
         the Holder of the Common Securities).

         (b) (i) The Trustee that acts as Property Trustee shall not be removed
in accordance with Section 5.7(a) until a Successor Property Trustee has been
appointed and has accepted such appointment by written instrument executed by
such Successor Property Trustee and delivered to the Administrative Trustees and
the Sponsor; and

                                       29
<PAGE>   36

                  (ii) the Trustee that acts as Delaware Trustee shall not be
         removed in accordance with Section 5.7(a) until a successor Trustee
         possessing the qualifications to act as Delaware Trustee under Sections
         5.2 and 5.4 (a "Successor Delaware Trustee") has been appointed and has
         accepted such appointment by written instrument executed by such
         Successor Delaware Trustee and delivered to the removed Delaware
         Trustee, the Property Trustee (if the removed Delaware Trustee is not
         also the Property Trustee), the Administrative Trustees and the
         Sponsor.

         (c) A Trustee appointed to office shall hold office until his successor
shall have been appointed or until his death, removal or resignation. Any
Trustee may resign from office (without need for prior or subsequent accounting)
by an instrument in writing signed by the Trustee and delivered to the other
Trustees, the Sponsor and the Trust, which resignation shall take effect upon
such delivery or upon such later date as is specified therein; provided,
however, that:

                  (i) No such resignation of the Trustee that acts as the
         Property Trustee shall be effective:

                           (A) until a Successor Property Trustee has been
                  appointed and has accepted such appointment by instrument
                  executed by such Successor Property Trustee and delivered to
                  the Trust, the Sponsor, the Delaware Trustee (if the resigning
                  Property Trustee is not also the Delaware Trustee) and the
                  resigning Property Trustee; or

                           (B) until the assets of the Trust have been
                  completely liquidated and the proceeds thereof distributed to
                  the Holders of the Securities; and

                  (ii) no such resignation of the Trustee that acts as the
         Delaware Trustee shall be effective until a Successor Delaware Trustee
         has been appointed and has accepted such appointment by instrument
         executed by such Successor Delaware Trustee and delivered to the Trust,
         the Property Trustee (if the resigning Delaware Trustee is not also the
         Property Trustee), the Sponsor and the resigning Delaware Trustee.

         (d) The Holders of the Common Securities or, if an Event of Default
shall have occurred and be continuing after the issuance of the Securities, the
Holders of the Preferred Securities shall use their best efforts to promptly
appoint a Successor Delaware Trustee or Successor Property Trustee, as the case
may be, if the Property Trustee or the Delaware Trustee delivers an instrument
of resignation in accordance with this Section 5.7.

         (e) If no Successor Property Trustee or Successor Delaware Trustee
shall have been appointed and accepted appointment as provided in this Section
5.7 within 60 days after delivery of an instrument of resignation or removal,
the Property Trustee or Delaware Trustee resigning or being removed, as
applicable, may petition any court of competent jurisdiction for appointment of
a Successor Property Trustee or Successor Delaware Trustee. Such court may
thereupon, after prescribing such notice, if any, as it may deem proper and
prescribe, appoint a Successor Property Trustee or Successor Delaware Trustee,
as the case may be.

                                       30

<PAGE>   37
         (f) No Property Trustee or Delaware Trustee shall be liable for the
acts or omissions to act of any Successor Property Trustee or Successor Delaware
Trustee, as the case may be.

SECTION 5.8       Vacancies among Trustees.

         If a Trustee ceases to hold office for any reason and the number of
Trustees is not reduced pursuant to Section 5.1, or if the number of Trustees is
increased pursuant to Section 5.1, a vacancy shall occur. A resolution
certifying the existence of such vacancy by the Administrative Trustees or, if
there are more than two, a majority of the Administrative Trustees shall be
conclusive evidence of the existence of such vacancy. The vacancy shall be
filled with a Trustee appointed in accordance with Section 5.7.

SECTION 5.9       Effect of Vacancies.

         The death, resignation, retirement, removal, bankruptcy, dissolution,
liquidation, incompetence or incapacity to perform the duties of a Trustee shall
not operate to dissolve, terminate or annul the Trust or to terminate this
Agreement. Whenever a vacancy in the number of Administrative Trustees shall
occur, until such vacancy is filled by the appointment of an Administrative
Trustee in accordance with Section 5.7, the Administrative Trustees in office,
regardless of their number, shall have all the powers granted to the
Administrative Trustees and shall discharge all the duties imposed upon the
Administrative Trustees by this Agreement.

SECTION 5.10      Meetings.

         If there is more than one Administrative Trustee, meetings of the
Administrative Trustees shall be held from time to time upon the call of any
Administrative Trustee. Regular meetings of the Administrative Trustees may be
held at a time and place fixed by resolution of the Administrative Trustees.
Notice of any in-person meetings of the Administrative Trustees shall be hand
delivered or otherwise delivered in writing (including by facsimile, with a hard
copy by overnight courier) not less than 24 hours before such meeting. Notice of
any telephonic meetings of the Administrative Trustees or any committee thereof
shall be hand delivered or otherwise delivered in writing (including by
facsimile, with a hard copy by overnight courier) not less than 24 hours before
a meeting. Notices shall contain a brief statement of the time, place and
anticipated purposes of the meeting. The presence (whether in person or by
telephone) of an Administrative Trustee at a meeting shall constitute a waiver
of notice of such meeting except where an Administrative Trustee attends a
meeting for the express purpose of objecting to the transaction of any activity
on the ground that the meeting has not been lawfully called or convened. Unless
provided otherwise in this Agreement, any action of the Administrative Trustees
may be taken at a meeting by vote of a majority of the Administrative Trustees
present (whether in person or by telephone) and eligible to vote with respect to
such matter, provided that a Quorum is present, or without a meeting by the
unanimous written consent of the Administrative Trustees. In the event there is
only one Administrative Trustee, any and all action of such Administrative
Trustee shall be evidenced by a written consent of such Administrative Trustee.

                                       31
<PAGE>   38
SECTION 5.11      Delegation of Power.

         (a) Any Administrative Trustee may, by power of attorney consistent
with applicable law, delegate to any other natural person over the age of 21 his
or her power for the purpose of executing any documents contemplated in Section
3.6, including any registration statement or amendment thereto filed with the
Commission; and

         (b) The Administrative Trustees shall have power to delegate from time
to time to such of their number or to officers of the Trust the doing of such
things and the execution of such instruments either in the name of the Trust or
the names of the Administrative Trustees or otherwise as the Administrative
Trustees may deem expedient, to the extent such delegation is not prohibited by
applicable law or contrary to the provisions of this Agreement.

SECTION 5.12      Merger, Conversion, Consolidation or Succession to Business.

         Any Person into which the Property Trustee or the Delaware Trustee or
any Administrative Trustee that is not a natural person, as the case may be, may
be merged or converted or with which it may be consolidated, or any Person
resulting from any merger, conversion or consolidation to which the Property
Trustee or the Delaware Trustee, as the case may be, shall be a party, or any
Person succeeding to all or substantially all the corporate trust business of
the Property Trustee or the Delaware Trustee, as the case may be, shall be the
successor of the Property Trustee or the Delaware Trustee, as the case may be,
hereunder, provided such Person shall be otherwise qualified and eligible under
this Article, without the execution or filing of any paper or any further act on
the part of any of the parties hereto; provided, however, such successor shall
notify the Sponsor and the Trust promptly of its succession.

SECTION 5.13      Compensation.

          The Sponsor agrees:

                  (a) to pay to the Property Trustee and the Delaware Trustee
from time to time such compensation as shall be agreed in writing between the
Company and the Property Trustee and the Delaware Trustee, respectively, for all
services rendered by them hereunder (which compensation shall not be limited by
any provision of law in regard to the compensation of a trustee of an express
trust); and

                  (b) to reimburse the Property Trustee and the Delaware Trustee
upon their request for reasonable expenses, disbursements and advances incurred
or made by the Property Trustee or the Delaware Trustee, respectively, in
accordance with any provision of this Agreement (including the reasonable
compensation and the expenses and advances of its agents and counsel), except
any such expense or advance as may be attributable to their negligence, willful
misconduct or bad faith.

                                       32
<PAGE>   39
                                   ARTICLE VI
                                  DISTRIBUTIONS

SECTION 6.1       Distributions.

         Holders shall receive Distributions in accordance with the applicable
terms of the relevant Holder's Securities. Distributions shall be made on the
Preferred Securities and the Common Securities in accordance with the respective
terms and preferences set forth herein and in Annex I. If and to the extent that
the Debenture Issuer makes a payment of interest (including any compounded
interest and additional interest), premium and/or principal on the Debentures
held by the Property Trustee (the amount of any such payment being a "Payment
Amount"), the Property Trustee shall and is directed, to the extent funds are
available for that purpose, to make a distribution (a "Distribution") of the
Payment Amount to Holders.

                                  ARTICLE VII
                             ISSUANCE OF SECURITIES

SECTION 7.1       General Provisions Regarding Securities.

         (a) The Administrative Trustees shall on behalf of the Trust issue one
class of preferred securities representing undivided beneficial interests in the
assets of the Trust having such terms as are set forth in Annex I (the
"Preferred Securities") and one class of common securities representing
undivided beneficial interests in the assets of the Trust having such terms as
are set forth in Annex I (the "Common Securities"). The Trust shall issue no
securities or other interests in the assets of the Trust other than the
Preferred Securities and the Common Securities.

         (b) The consideration received by the Trust for the issuance of the
Securities shall constitute a contribution to the capital of the Trust and shall
not constitute a loan to the Trust.

         (c) Upon issuance of the Securities as provided in this Agreement, the
Securities so issued shall be validly issued, fully paid and non-assessable.

         (d) Every Person, by virtue of having become a Holder or a Preferred
Security Beneficial Owner in accordance with the terms of this Agreement, shall
be deemed to have expressly assented and agreed to the terms of, and shall be
bound by, this Agreement.

SECTION 7.2       Execution and Authentication.

         (a) The Securities shall be signed on behalf of the Trust by an
Administrative Trustee. In case any Administrative Trustee of the Trust who
shall have signed any of the Securities shall cease to be such Administrative
Trustee before the Securities so signed shall be delivered by the Trust, such
Securities nevertheless may be delivered as though the Person who signed such
Securities had not ceased to be such Administrative Trustee; and any Securities
may be signed on behalf of the Trust by such persons who, at the actual date of
execution of such Security, shall be the Administrative Trustees of the Trust,
although at the date of the execution and delivery of this Agreement any such
person was not an Administrative Trustee.

                                       33
<PAGE>   40
         (b) One Administrative Trustee shall sign the Preferred Securities for
the Trust by manual or facsimile signature.

         A Preferred Security shall not be valid until authenticated by the
manual signature of an authorized signatory of the Property Trustee. The
signature shall be conclusive evidence that the Preferred Security has been
authenticated under this Agreement. A Common Security shall be valid upon
execution by an Administrative Trustee without any act of the Property Trustee.

         Upon a written order of the Trust signed by one Administrative Trustee,
the Property Trustee shall authenticate the Preferred Securities for original
issue.

         The aggregate number of Preferred Securities outstanding at any time
shall not exceed the number set forth in the terms in Annex I hereto except as
provided in Section 7.6.

         The Property Trustee may appoint an authenticating agent acceptable to
the Trust to authenticate Preferred Securities. An authenticating agent may
authenticate Preferred Securities whenever the Property Trustee may do so. Each
reference in this Agreement to authentication by the Property Trustee includes
authentication by such agent. An authenticating agent has the same rights as the
Property Trustee hereunder with respect to the Sponsor or an Affiliate.

SECTION 7.3       Form and Dating.

         The Preferred Securities and the Property Trustee's certificate of
authentication shall be substantially in the form of Exhibit A-1 and the Common
Securities shall be substantially in the form of Exhibit A-2, each of which is
hereby incorporated in and expressly made a part of this Agreement. The
Preferred Securities shall be issued only in minimum denominations of $1,000,000
Liquidation Amount and integral multiples of $1,000 in excess thereof. The
Securities may be in definitive or global form and may be printed, lithographed
or engraved or may be produced in any other manner as is reasonably acceptable
to an Administrative Trustee, as evidenced by the execution thereof. The
Securities may have letters, CUSIP or other numbers, notations or other marks of
identification or designation and such legends or endorsements required by law,
stock exchange or quotation system rule, agreements to which the Trust is
subject, if any, or usage (provided that any such notation, legend or
endorsement is in a form acceptable to the Trust). An Administrative Trustee, at
the direction of the Sponsor, shall furnish any such legend not contained in
Exhibits A-1 or A-2 to the Property Trustee in writing. Each Preferred Security
shall be dated the date of its authentication. The terms and provisions of the
Securities set forth in Annex I and the forms of Securities set forth in
Exhibits A-1 and A-2 are part of the terms of this Agreement and to the extent
applicable, the Property Trustee and the Sponsor, by their execution and
delivery of this Agreement, expressly agree to such terms and provisions and to
be bound thereby.

         The following four paragraphs shall apply only to any Global Preferred
Securities:

                                       34
<PAGE>   41
         The Preferred Securities shall be issued in the form of one or more
permanent global Securities in definitive, fully registered form without
Distribution coupons with the appropriate global legends set forth in Exhibit
A-1 hereto (a "Global Preferred Security"), which shall be deposited on behalf
of the purchasers of the Preferred Securities represented thereby with the
Property Trustee, as custodian for the Clearing Agency, and registered in the
name of the Clearing Agency or a nominee of the Clearing Agency, duly executed
by an Administrative Trustee on behalf of the Trust and authenticated by the
Property Trustee as hereinafter provided. The number of Preferred Securities
represented by the Global Preferred Security may from time to time be increased
or decreased by adjustments made on the records of the Property Trustee and the
Clearing Agency or its nominee as hereinafter provided. The Holder of a Global
Preferred Security may grant proxies and otherwise authorize any Person,
including Participants and Persons that may hold interests through Participants,
to take any action which such Holder is entitled to take under this Agreement or
the Securities.

         An Administrative Trustee shall execute and the Property Trustee shall,
in accordance with this Section 7.3, authenticate and make available for
delivery initially one or more Global Preferred Securities that (i) shall be
registered in the name of Cede & Co. or other nominee of such Clearing Agency
and (ii) shall be delivered by the Property Trustee to such Clearing Agency or
pursuant to such Clearing Agency's written instructions or held by the Property
Trustee as custodian for the Clearing Agency.

         Members of, or participants in, the Clearing Agency ("Participants")
shall have no rights under this Agreement with respect to any Global Preferred
Security held on their behalf by the Clearing Agency or by the Property Trustee
as the custodian of the Clearing Agency or under such Global Preferred Security,
and the Clearing Agency may be treated by the Trust, the Property Trustee and
any agent of the Trust or the Property Trustee as the absolute owner of such
Global Preferred Security for all purposes whatsoever. Notwithstanding the
foregoing, nothing herein shall prevent the Trust, the Property Trustee or any
agent of the Trust or the Property Trustee from giving effect to any written
certification, proxy or other authorization furnished by the Clearing Agency or
impair, as between the Clearing Agency and its Participants, the operation of
customary practices of such Clearing Agency governing the exercise of the rights
of a holder of a beneficial interest in any Global Preferred Security.

         Except as provided in Section 9.2, owners of beneficial interests in a
Global Preferred Security will not be entitled to receive physical delivery of
Preferred Securities in definitive form ("Definitive Preferred Securities").

SECTION 7.4       Registrar and Paying Agent.

         The Trust shall maintain in the Borough of Manhattan, The City of New
York, (i) an office or agency where Preferred Securities may be presented for
registration of transfer ("Registrar") and (ii) an office or agency where
Preferred Securities may be presented for payment ("Paying Agent"). The
Registrar shall keep a register of the Preferred Securities and of their
transfer. The Trust may appoint the Registrar and the Paying Agent and may
appoint one or more co-registrars and one or more additional paying agents in
such other locations as it shall determine. The term "Registrar" includes any
additional registrar and the term "Paying Agent" includes any additional paying
agent. The Trust may change any Registrar or Paying Agent

                                       35
<PAGE>   42
without prior notice to any Holder. The Administrative Trustees shall notify the
Property Trustee of the name and address of any Agent not a party to this
Agreement. If the Trust fails to appoint or maintain another entity as Registrar
or Paying Agent, the Property Trustee shall act as such, and as Paying Agent the
Property Trustee shall have the rights set forth in Section 3.8(i). The Trust or
any of its Affiliates may act as Registrar or Paying Agent. The Trust shall act
as Registrar and Paying Agent for the Common Securities.

         Any Paying Agent shall be permitted to resign as Paying Agent upon 30
days' prior written notice to the Property Trustee, the Administrative Trustees
and the Sponsor. In the event that the Property Trustee shall no longer be the
Paying Agent, the Trust shall appoint a successor Paying Agent (which shall be a
bank or trust company acceptable to the Sponsor) to act as Paying Agent.

         The Trust initially appoints the Property Trustee as Registrar and
Paying Agent for the Preferred Securities.

SECTION 7.5       Paying Agent to Hold Money in Trust.

         The Trust shall require each Paying Agent other than the Property
Trustee to agree in writing that the Paying Agent will hold in trust for the
benefit of Holders or the Property Trustee all money held by the Paying Agent
for the payment of liquidation amounts or Distributions on the Securities and
will notify the Property Trustee if there are insufficient funds for such
purpose. While any such insufficiency continues, the Property Trustee may
require a Paying Agent to pay all money held by it to the Property Trustee. The
Trust at any time may require a Paying Agent to pay all money held by it to the
Property Trustee and to account for any money disbursed by it. Upon payment over
to the Property Trustee, the Paying Agent (if other than the Trust or an
Affiliate of the Trust) shall have no further liability for the money. If the
Trust or the Sponsor or an Affiliate of the Trust or the Sponsor acts as Paying
Agent, it shall segregate and hold in a separate trust fund for the benefit of
the Holders all money held by it as Paying Agent.

SECTION 7.6       Replacement Securities.

         If a Holder of a Security claims that a Security owned by it has been
lost, destroyed or wrongfully taken or if such Security is mutilated and is
surrendered to the Trust or, in the case of the Preferred Securities, to the
Property Trustee, an Administrative Trustee shall execute and the Property
Trustee shall authenticate and make available for delivery a replacement
Security if the Property Trustee's and the Trust's requirements, as the case may
be, are met. An indemnity bond must be provided by the Holder which, in the
judgment of the Property Trustee, is sufficient to protect the Trustees, the
Sponsor or any authenticating agent from any loss which any of them may suffer
if a Security is replaced. The Trust may charge such Holder for its expenses in
replacing a Security.

         Every replacement Security is an additional beneficial interest in the
Trust.

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<PAGE>   43
SECTION 7.7       Outstanding Preferred Securities.

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

         If a Preferred Security is replaced, paid or purchased pursuant to
Section 7.6 hereof, it ceases to be outstanding unless the Property Trustee
receives proof satisfactory to it that the replaced, paid or purchased Preferred
Security is held by a bona fide purchaser.

         If Preferred Securities are considered paid in accordance with the
terms of this Agreement, they cease to be outstanding and Distributions thereon
shall cease to accumulate.

         A Preferred Security does not cease to be outstanding because the
Trust, the Sponsor or an Affiliate of the Sponsor holds such Preferred Security.

SECTION 7.8       Preferred Securities in Treasury.

         In determining whether the Holders of the required amount of Preferred
Securities have concurred in any direction, waiver or consent, Preferred
Securities owned by the Trust, the Sponsor or an Affiliate of the Sponsor, as
the case may be, shall be disregarded and deemed not to be outstanding, except
that for the purposes of determining whether the Property Trustee shall be fully
protected in relying on any such direction, waiver or consent, only Preferred
Securities which a Responsible Officer of the Property Trustee actually knows
are so owned shall be so disregarded.

SECTION 7.9       Temporary Securities.

         Until Definitive Securities are ready for delivery, the Administrative
Trustees may prepare and, in the case of the Preferred Securities, the Property
Trustee shall authenticate temporary Securities. Temporary Securities shall be
substantially in the form of Definitive Securities but may have variations that
the Trust considers appropriate for temporary Securities. Without unreasonable
delay, the Administrative Trustees shall prepare and, in the case of the
Preferred Securities, the Property Trustee shall authenticate Definitive
Securities in exchange for temporary Securities.

SECTION 7.10      Cancellation.

         The Trust at any time may deliver Preferred Securities to the Property
Trustee for cancellation. The Registrar and Paying Agent shall forward to the
Property Trustee any Preferred Securities surrendered to them for registration
of transfer, redemption, exchange or payment. The Property Trustee shall
promptly cancel all Preferred Securities surrendered for registration of
transfer, redemption, exchange, payment, replacement or cancellation and shall
dispose of cancelled Preferred Securities as the Trust directs, provided that
the Property Trustee shall not be obligated to destroy Preferred Securities. The
Trust may not issue new Preferred Securities to replace Preferred Securities
that it has paid or redeemed or that have been delivered to the Property Trustee
for cancellation or that any Holder has exchanged.

                                       37
<PAGE>   44
SECTION 7.11      CUSIP Numbers.

                  The Trust, in issuing the Preferred Securities, may use
"CUSIP" numbers (if then generally in use), and, if so, the Property Trustee
shall use "CUSIP" numbers in notices of redemption as a convenience to Holders
of Preferred Securities; provided that any such notice may state that no
representation is made as to the correctness of such numbers either as printed
on the Preferred Securities or as contained in any notice of a redemption and
that reliance may be placed only on the other identification numbers printed on
the Preferred Securities, and any such redemption shall not be affected by any
defect in or omission of such numbers. The Sponsor will promptly notify the
Property Trustee of any change in the CUSIP numbers.

                                  ARTICLE VIII
                              DISSOLUTION OF TRUST

SECTION 8.1       Dissolution of Trust.

         (a) The Trust shall automatically dissolve upon the first to occur of
the following events:

                  (i) the bankruptcy of the Sponsor;

                  (ii) (A) the filing of a certificate of dissolution or
         liquidation or its equivalent with respect to the Sponsor or (B) the
         revocation of the Sponsor's charter and the expiration of 90 days after
         the date of revocation without a reinstatement thereof;

                  (iii) the distribution of a Like Amount of the Debentures to
         the Holders of the Securities, provided that the Property Trustee has
         received written notice from the Sponsor directing the Property Trustee
         to dissolve the Trust (which direction is optional and, except as
         otherwise expressly provided herein, within the discretion of the
         Sponsor), and provided, further, that such dissolution is conditioned
         on the receipt by the Administrative Trustees of an opinion of an
         independent tax counsel experienced in such matters (a "No Recognition
         Opinion") to the effect that the Holders of the Securities will not
         recognize any gain or loss for United States Federal income tax
         purposes as a result of the dissolution of the Trust and the
         distribution of the Debentures;

                  (iv) the entry of a decree of judicial dissolution of the
         Trust by a court of competent jurisdiction;

                  (v) the redemption of all of the Securities and the payment to
         the Holders of any and all amounts necessary therefor, all in
         accordance with the terms of the Securities; or

                  (vi) the expiration of the term of the Trust provided in
         Section 3.14.

         (b) As soon as is practicable upon completion of winding up of the
Trust following the occurrence of an event referred to in Section 8.1(a), the
Administrative Trustees

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<PAGE>   45
shall terminate the Trust by filing a certificate of cancellation with the
Secretary of State of the State of Delaware in accordance with the Business
Trust Act.

         (c) The provisions of Section 3.9 and Article X shall survive the
termination of the Trust.

                                   ARTICLE IX
                              TRANSFER OF INTERESTS

SECTION 9.1       Transfer of Securities.

         (a) Securities may only be transferred, in whole or in part, in
accordance with the terms and conditions set forth in this Agreement and in the
terms of the Securities. To the fullest extent permitted by law, any transfer or
purported transfer of any Security not made in accordance with this Agreement
shall be null and void.

         (b) Subject to this Article IX, Preferred Securities shall be freely
transferable.

         (c) To the fullest extent permitted by law, the Sponsor may not
transfer the Common Securities except for any transfer (whether voluntarily or
by operation of law) permitted under Article 5 of the Indenture.

         (d) Each Security that bears or is required to bear the legend set
forth in this Section 9.1 (a "RESTRICTED SECURITY") shall be subject to the
restrictions on transfer provided in the legend set forth in this Section 9.1,
unless such restrictions on transfer shall be waived by the written consent of
the Administrative Trustees, and the Holder of each Restricted Security, by such
Holder's acceptance thereof, agrees to be bound by such restrictions on
transfer. As used in this Section 9.1 and in Section 9.2, the terms "transfer"
encompasses any sale, pledge, transfer or other disposition of any Restricted
Security.

         Prior to the Transfer Restriction Termination Date, any certificate
evidencing a Security shall bear a legend in substantially the following form,
unless otherwise agreed by the Administrative Trustees (with written notice
thereof to the Property Trustee):

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS. NEITHER THIS
SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT
SUBJECT TO, REGISTRATION UNDER THE SECURITIES ACT AND ANY APPLICABLE STATE
SECURITIES LAWS.

THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES NOT TO OFFER, SELL
OR OTHERWISE TRANSFER SUCH SECURITY PRIOR TO THE DATE (THE "RESALE RESTRICTION
TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUE DATE
HEREOF AND THE LAST DATE ON

                                       39
<PAGE>   46
WHICH HERCULES TRUST VI (THE "TRUST") OR ANY AFFILIATED PERSON OF THE TRUST WAS
THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY) UNLESS SUCH
OFFER, SALE OR OTHER TRANSFER IS (A) TO THE TRUST OR HERCULES INCORPORATED OR
ANY OF ITS SUBSIDIARIES, (B) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN
DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS THE SECURITIES
ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A, TO A PERSON WHO IS OR WHO THE
HOLDER REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN
RULE 144A UNDER THE SECURITIES ACT THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE
ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE
TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) TO AN "ACCREDITED INVESTOR"
(AS DEFINED IN RULE 501 (A)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT) THAT
IS AN INSTITUTIONAL INVESTOR, (E) PURSUANT TO OFFERS AND SALES TO NON-U.S.
PERSONS THAT OCCUR OUTSIDE THE UNITED STATES WITHIN THE MEANING OF REGULATION S
UNDER THE SECURITIES ACT OR (F) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION FROM
THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE RIGHT OF THE
TRUST OR THE TRANSFER AGENT FOR THE SECURITIES PRIOR TO ANY SUCH OFFER, SALE OR
TRANSFER PURSUANT TO CLAUSES (D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN
OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH
OF THEM. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE THEN HOLDER OF THIS
SECURITY AFTER THE RESALE RESTRICTION TERMINATION DATE.

         The Preferred Securities may be transferred or exchanged only in
minimum denominations of $1,000,000 Liquidation Amount and integral multiples of
$1,000 in excess thereof, and any attempted transfer, sale or other disposition
of Preferred Securities in a denomination of less than $1,000,000 Liquidation
Amount shall be deemed to be void and of no legal effect whatsoever.

         Following the Transfer Restriction Termination Date, any Security or
Securities issued in exchange or substitution therefor (other than Securities
acquired by the Sponsor or any Affiliate) may, upon surrender of such Security
or Securities for exchange to the Trustee in accordance with the provisions of
this Section 9.1, be exchanged for a new Security or Securities, as the case may
be, in a like aggregate Liquidation Amount and of like tenor that shall not bear
the restrictive legend required by this Section 9.1.

         Any Security that, prior to the Transfer Restriction Termination Date,
is purchased or owned by the Sponsor, the Trust or any Affiliate thereof may not
be resold by the Sponsor, the Trust or such Affiliate unless registered under
the Securities Act or resold pursuant to an exemption from the registration
requirements thereof.

         (e) The Administrative Trustees shall provide for the registration of
Securities and of the transfer of Securities, which will be effected without
charge but only upon payment (with such indemnity as the Administrative Trustees
may require) in respect of any tax or other governmental charges that may be
imposed in relation to it. Upon surrender for registration of

                                       40
<PAGE>   47
transfer of any Securities, the Administrative Trustees shall cause one or more
new Securities to be issued in the name of the designated transferee or
transferees. Every Security surrendered for registration of transfer or exchange
shall be accompanied by a written instrument of transfer in form satisfactory to
the Administrative Trustees duly executed by the Holder or such Holder's
attorney duly authorized in writing. Each Security surrendered for registration
of transfer shall be canceled by the Administrative Trustees. A transferee of a
Security shall be entitled to the rights and subject to the obligations of a
Holder hereunder upon the receipt by such transferee of a Security. By
acceptance of a Security, each transferee shall be deemed to have agreed to be
bound by this Agreement.

SECTION 9.2       Transfer Procedures and Restrictions

         (a) Transfer and Exchange of Definitive Preferred Securities. When
Definitive Preferred Securities are presented to the Registrar:

                  (x) to register the transfer of such Definitive Preferred
         Securities; or

                  (y) to exchange such Definitive Preferred Securities which
         became mutilated, destroyed, defaced, stolen or lost, for an equal
         liquidation amount of Definitive Preferred Securities,

the Registrar shall register the transfer or make the exchange as requested if
its reasonable requirements for such transaction are met; provided, however,
that the Definitive Preferred Securities surrendered for transfer or exchange
shall be duly endorsed or accompanied by a written instrument of transfer in
form reasonably satisfactory to the Property Trustee and the Registrar, duly
executed by the Holder thereof or his attorney duly authorized in writing.

         (b) Transfer of a Definitive Preferred Security for a Beneficial
Interest in a Global Preferred Security. Upon receipt by the Property Trustee of
a Definitive Preferred Security, duly endorsed or accompanied by appropriate
instruments of transfer, in form satisfactory to the Property Trustee, together
with written instructions directing the Property Trustee to make, or to direct
the Clearing Agency to make, an adjustment on its books and records with respect
to the Global Preferred Security to reflect an increase in the Liquidation
Amount of the Preferred Securities represented by such Global Preferred
Security, then the Property Trustee shall cancel such Definitive Preferred
Security and cause, or direct the Clearing Agency to cause, the aggregate
Liquidation Amount of Preferred Securities represented by the appropriate Global
Preferred Security to be increased accordingly. If no Global Preferred
Securities are then outstanding, an Administrative Trustee shall execute on
behalf of the Trust and the Property Trustee shall authenticate, upon written
order of any Administrative Trustee, a Global Preferred Security representing an
appropriate Liquidation Amount of Preferred Securities.

         (c) Transfer and Exchange of Global Preferred Securities. Subject to
Section 9.2(d), the transfer and exchange of Global Preferred Securities or
beneficial interests therein shall be effected through the Clearing Agency in
accordance with this Agreement and the procedures of the Clearing Agency
therefor.

                                       41
<PAGE>   48
         (d) Transfer of a Beneficial Interest in a Global Preferred Security
for a Definitive Preferred Security.

                  (i) A Global Preferred Security deposited with the Clearing
         Agency or with the Property Trustee as custodian for the Clearing
         Agency pursuant to Section 7.3 shall be transferred to the beneficial
         owners thereof in the form of Definitive Preferred Securities only if
         such transfer complies with Section 9.2(c) and (1) the Clearing Agency
         notifies the Trust that it is unwilling or unable to continue as
         Clearing Agency for such Global Preferred Security or if at any time
         such Clearing Agency ceases to be a "clearing agency" registered under
         the Exchange Act and, in each case, a clearing agency is not appointed
         by the Sponsor within 90 days of receipt of such notice or of becoming
         aware of such condition, (2) a Default or an Event of Default has
         occurred and is continuing or (3) the Trust at its sole discretion
         elects to cause the issuance of Definitive Preferred Securities.

                  (ii) Any Global Preferred Security that is transferable to the
         beneficial owners thereof in the form of Definitive Preferred
         Securities pursuant to this Section 9.2(d) shall be surrendered by the
         Clearing Agency to the Property Trustee located in the Borough of
         Manhattan, The City of New York, to be so transferred, in whole or from
         time to time in part, without charge, and the Property Trustee shall
         authenticate and make available for delivery, upon such transfer of
         each portion of such Global Preferred Security, an equal aggregate
         Liquidation Amount of Securities of authorized denominations in the
         form of Definitive Preferred Securities. Any portion of a Global
         Preferred Security transferred pursuant to this Section shall be
         registered in such names as the Clearing Agency shall direct.

         In the event of the occurrence of any of the events specified in clause
(i) above, the Administrative Trustees will promptly make available to the
Property Trustee a reasonable supply of Definitive Preferred Securities in fully
registered form without Distribution coupons.

         (e) Restrictions on Transfer and Exchange of Global Preferred
Securities. Notwithstanding any other provisions of this Agreement (other than
the provisions set forth in subsection (d) of this Section 9.2), a Global
Preferred Security may not be transferred as a whole except by the Clearing
Agency to a nominee of the Clearing Agency or another nominee of the Clearing
Agency or by the Clearing Agency or any such nominee to a successor Clearing
Agency or a nominee of such successor Clearing Agency.

         (f) Cancellation or Adjustment of Global Preferred Security. At such
time as all beneficial interests in a Global Preferred Security have either been
exchanged for Definitive Preferred Securities to the extent permitted by this
Agreement or redeemed, repurchased or canceled in accordance with the terms of
this Agreement, such Global Preferred Security shall be returned to the Clearing
Agency for cancellation or retained and canceled by the Property Trustee. At any
time prior to such cancellation, if any beneficial interest in a Global
Preferred Security is exchanged for Definitive Preferred Securities, Preferred
Securities represented by such Global Preferred Security shall be reduced and an
adjustment shall be made on the books and records of the Property Trustee (if it
is then the custodian for such Global Preferred Security)

                                       42
<PAGE>   49
with respect to such Global Preferred Security, by the Property Trustee or the
Securities Custodian, to reflect such reduction.

         (g) Obligations with Respect to Transfers and Exchanges of Preferred
Securities.

                  (i) To permit registrations of transfers and exchanges, an
         Administrative Trustee shall execute and the Property Trustee shall
         authenticate Definitive Preferred Securities and Global Preferred
         Securities at the Registrar's request in accordance with the terms of
         this Agreement.

                  (ii) Registrations of transfers or exchanges will be effected
         without charge, but only upon payment (with such indemnity as the Trust
         or the Sponsor may require) in respect of any tax or other governmental
         charge that may be imposed in relation to it.

                  (iii) The Registrar shall not be required to register the
         transfer of or exchange of (a) Preferred Securities during a period
         beginning at the opening of business 15 days before the day of mailing
         of a notice of redemption or any notice of selection of Preferred
         Securities for redemption and ending at the close of business on the
         day of such mailing; or (b) any Preferred Security so selected for
         redemption in whole or in part, except the unredeemed portion of any
         Preferred Security being redeemed in part.

                  (iv) All Preferred Securities issued upon any registration of
         transfer or exchange pursuant to the terms of this Agreement shall
         evidence the same security and shall be entitled to the same benefits
         under this Agreement as the Preferred Securities surrendered upon such
         registration of transfer or exchange.

         (h) No Obligation of the Property Trustee.

                  (i) The Property Trustee shall have no responsibility or
         obligation to any beneficial owner of a Global Preferred Security, a
         Participant in the Clearing Agency or other Person with respect to the
         accuracy of the records of the Clearing Agency or its nominee or of any
         Participant thereof, with respect to any ownership interest in the
         Preferred Securities or with respect to the delivery to any
         Participant, beneficial owner or other Person (other than the Clearing
         Agency) of any notice (including any notice of redemption) or the
         payment of any amount, under or with respect to such Preferred
         Securities. All notices and communications to be given to the Holders
         and all payments to be made to Holders under the Preferred Securities
         shall be given or made only to or upon the order of the Holders (which
         shall be the Clearing Agency or its nominee in the case of a Global
         Preferred Security). The rights of beneficial owners in any Global
         Preferred Security shall be exercised only through the Clearing Agency
         subject to the applicable rules and procedures of the Clearing Agency.
         The Property Trustee may conclusively rely and shall be fully protected
         in relying upon information furnished by the Clearing Agency or any
         agent thereof with respect to its Participants and any beneficial
         owners.

                  (ii) The Property Trustee and Registrar shall have no
         obligation or duty to monitor, determine or inquire as to compliance
         with any restrictions on transfer imposed

                                       43
<PAGE>   50
         under this Agreement or under applicable law with respect to any
         transfer of any interest in any Preferred Security (including any
         transfers between or among Clearing Agency Participants or beneficial
         owners in any Global Preferred Security) other than to require delivery
         of such certificates and other documentation or evidence as are
         expressly required by, and to do so if and when expressly required by,
         the terms of this Agreement, and to examine the same to determine
         substantial compliance as to form with the express requirements hereof.

SECTION 9.3       Deemed Security Holders.

         The Trust, the Trustees, the Registrar and the Paying Agent may treat
the Person in whose name any Security shall be registered on the books and
records of the Trust as the sole owner and Holder of such Security for purposes
of receiving Distributions and for all other purposes whatsoever and,
accordingly, shall not be bound to recognize any equitable or other claim to or
interest in such Security on the part of any Person other than such Holder,
regardless of any notice to the contrary.

SECTION 9.4       Book Entry Interests.

         Global Preferred Securities shall initially be registered on the books
and records of the Trust in the name of Cede & Co., the nominee of the Clearing
Agency, and no Preferred Security Beneficial Owner will receive a definitive
Preferred Security Certificate representing such Preferred Security Beneficial
Owner's interests in such Global Preferred Securities, except as provided in
Section 9.2. Unless and until Definitive Preferred Securities have been issued
to the Preferred Security Beneficial Owners pursuant to Section 9.2:

         (a) the provisions of this Section 9.4 shall be in full force and
effect;

         (b) the Trust and the Trustees shall be entitled to deal with the
Clearing Agency for all purposes of this Agreement (including the payment of
Distributions on the Global Preferred Securities and receiving approvals, votes
or consents hereunder) as the Holder of the Preferred Securities and the sole
holder of the Global Certificates and shall have no obligation to the Preferred
Security Beneficial Owners;

         (c) to the extent that the provisions of this Section 9.4 conflict with
any other provisions of this Agreement, the provisions of this Section 9.4 shall
control; and

         (d) the rights of the Preferred Security Beneficial Owners shall be
exercised only through the Clearing Agency and shall be limited to those
established by law and agreements between such Preferred Security Beneficial
Owners and the Clearing Agency and/or the Participants, including receiving and
transmitting payments of Distributions on the Global Certificates to such
Participants. DTC will make book entry transfers among the Participants.

         Any Global Preferred Security may be endorsed with or have incorporated
in the text thereof such legends or recitals or changes not inconsistent with
the provisions of this Agreement as may be required by the Clearing Agency, by
any exchange or by the National

                                       44
<PAGE>   51
Association of Securities Dealers, Inc. in order for the Preferred Securities to
be tradeable on the PORTAL Market or as may be required for the Preferred
Securities to be tradeable on any other market developed for trading of
securities pursuant to Rule 144A or required to comply with any applicable law
or any regulation thereunder or with the rules and regulations of any securities
exchange upon which the Preferred Securities may be listed or traded or to
conform with any usage with respect thereto, or to indicate any special
limitations or restrictions to which any particular Preferred Securities are
subject.

SECTION 9.5       Notices to Clearing Agency.

         Whenever a notice or other communication to the Preferred Security
Holders is required to be given by a Trustee under this Agreement, such Trustee
shall give all such notices and communications specified herein to be given to
the Holders of Global Preferred Securities to the Clearing Agency and shall have
no notice obligations to the Preferred Security Beneficial Owners.

SECTION 9.6       Appointment of Successor Clearing Agency.

         If any Clearing Agency elects to discontinue its services as securities
depositary with respect to the Preferred Securities, the Administrative Trustees
may, in their sole discretion, appoint a successor Clearing Agency with respect
to the Preferred Securities.

                                   ARTICLE X
                           LIMITATION OF LIABILITY OF
                    HOLDERS OF SECURITIES, TRUSTEES OR OTHERS

SECTION 10.1      Liability.

         (a) Except as expressly set forth in this Agreement, the Securities
Guarantees and the terms of the Securities, the Sponsor shall not be:

                  (i) personally liable for the return of any portion of the
         capital contributions (or any return thereon) of the Holders of the
         Securities which shall be made solely from assets of the Trust; and

                  (ii) required to pay to the Trust or to any Holder of
         Securities any deficit upon dissolution of the Trust or otherwise.

         (b) The Sponsor shall be liable for all of the debts and obligations of
the Trust (other than with respect to the Securities) to the extent not
satisfied out of the Trust's assets.

         (c) Pursuant to Section 3803(a) of the Business Trust Act, the Holders
of the Preferred Securities shall be entitled to the same limitation of personal
liability extended to stockholders of private corporations for profit organized
under the General Corporation Law of the State of Delaware.

                                       45
<PAGE>   52
SECTION 10.2      Exculpation.

         (a) No Indemnified Person shall be liable, responsible or accountable
in damages or otherwise to the Trust or any Covered Person for any loss, damage
or claim incurred by reason of any act or omission performed or omitted by such
Indemnified Person in good faith on behalf of the Trust and in a manner such
Indemnified Person reasonably believed to be within the scope of the authority
conferred on such Indemnified Person by this Agreement or by law, except that
this provision shall not be deemed to modify Section 3.9(b).

         (b) An Indemnified Person shall be fully protected in relying in good
faith upon the records of the Trust and upon such information, opinions, reports
or statements presented to the Trust by any Person as to matters the Indemnified
Person reasonably believes are within such other Person's professional or expert
competence and who has been selected with reasonable care by or on behalf of the
Trust, including information, opinions, reports or statements as to the value
and amount of the assets, liabilities, profits, losses, or any other facts
pertinent to the existence and amount of assets from which Distributions to
Holders of Securities might properly be paid.

SECTION 10.3      Fiduciary Duty.

         (a) To the extent that, at law or in equity, an Indemnified Person has
duties (including fiduciary duties) and liabilities relating thereto to the
Trust or to any other Covered Person, an Indemnified Person acting under this
Agreement shall not be liable to the Trust or to any other Covered Person for
its good faith reliance on the provisions of this Agreement. The provisions of
this Agreement, to the extent that they restrict the duties and liabilities of
an Indemnified Person otherwise existing at law or in equity (other than the
duties imposed on the Property Trustee under the Trust Indenture Act), are
agreed by the parties hereto to replace such other duties and liabilities of
such Indemnified Person.

         (b) Unless otherwise expressly provided herein:

                  (i) whenever a conflict of interest exists or arises between
         any Covered Person and any Indemnified Person; or

                  (ii) whenever this Agreement or any other agreement
         contemplated herein or therein provides that an Indemnified Person
         shall act in a manner that is, or provides terms that are, fair and
         reasonable to the Trust or any Holder of Securities,

the Indemnified Person shall resolve such conflict of interest, take such action
or provide such terms, considering in each case the relative interest of each
party (including its own interest) to such conflict, agreement, transaction or
situation and the benefits and burdens relating to such interests, any customary
or accepted industry practices, and any applicable generally accepted accounting
practices or principles. In the absence of bad faith by the Indemnified Person,
the resolution, action or term so made, taken or provided by the Indemnified
Person shall not constitute a breach of this Agreement or any other agreement
contemplated herein or of any duty or obligation of the Indemnified Person at
law or in equity or otherwise.

                                       46
<PAGE>   53
         (c) Whenever in this Agreement an Indemnified Person is permitted or
required to make a decision:

                  (i) in its "discretion" or under a grant of similar authority,
         the Indemnified Person shall be entitled to consider such interests and
         factors as it desires, including its own interests, and shall have no
         duty or obligation to give any consideration to any interest of or
         factors affecting the Trust or any other Person; or

                  (ii) in its "good faith" or under another express standard,
         the Indemnified Person shall act under such express standard and shall
         not be subject to any other or different standard imposed by this
         Agreement or by applicable law.

SECTION 10.4      Indemnification.

                  (a) (i) The Sponsor shall indemnify, to the full extent
         permitted by law, any Company Indemnified Person who was or is a party
         or is threatened to be made a party to any threatened, pending or
         completed action, suit or proceeding, whether civil, criminal,
         administrative or investigative (other than an action by or in the
         right of the Trust) by reason of the fact that he is or was a Company
         Indemnified Person against expenses (including attorneys' fees and
         expenses), judgments, fines and amounts paid in settlement actually and
         reasonably incurred by him in connection with such action, suit or
         proceeding if he acted in good faith and in a manner he reasonably
         believed to be in or not opposed to the best interests of the Trust,
         and, with respect to any criminal action or proceeding, had no
         reasonable cause to believe his conduct was unlawful. The termination
         of any action, suit or proceeding by judgment, order, settlement,
         conviction, or upon a plea of nolo contendere or its equivalent, shall
         not, of itself, create a presumption that the Company Indemnified
         Person did not act in good faith and in a manner which he reasonably
         believed to be in or not opposed to the best interests of the Trust,
         and, with respect to any criminal action or proceeding, had reasonable
         cause to believe that his conduct was unlawful.

                  (ii) The Sponsor shall indemnify, to the full extent permitted
         by law, any Company Indemnified Person who was or is a party or is
         threatened to be made a party to any threatened, pending or completed
         action or suit by or in the right of the Trust to procure a judgment in
         its favor by reason of the fact that he is or was a Company Indemnified
         Person against expenses (including attorneys' fees and expenses)
         actually and reasonably incurred by him in connection with the defense
         or settlement of such action or suit if he acted in good faith and in a
         manner he reasonably believed to be in or not opposed to the best
         interests of the Trust and except that no such indemnification shall be
         made in respect of any claim, issue or matter as to which such Company
         Indemnified Person shall have been adjudged to be liable to the Trust
         unless and only to the extent that the Court of Chancery of Delaware or
         the court in which such action or suit was brought shall determine upon
         application that, despite the adjudication of liability but in view of
         all the circumstances of the case, such Company Indemnified Person is
         fairly and reasonably entitled to indemnity for such expenses which
         such Court of Chancery or such other court shall deem proper.

                                       47
<PAGE>   54
                     (iii) To the extent that a Company Indemnified Person shall
         be successful on the merits or otherwise (including dismissal of an
         action without prejudice or the settlement of an action without
         admission of liability) in defense of any action, suit or proceeding
         referred to in paragraphs (i) and (ii) of this Section 10.4(a), or in
         defense of any claim, issue or matter therein, he shall be indemnified,
         to the full extent permitted by law, against expenses (including
         attorneys' fees) actually and reasonably incurred by him in connection
         therewith.

                     (iv) Any indemnification under paragraphs (i) and (ii) of
         this Section 10.4(a) (unless ordered by a court) shall be made by the
         Sponsor only as authorized in the specific case upon a determination
         that indemnification of the Company Indemnified Person is proper in the
         circumstances because he has met the applicable standard of conduct set
         forth in paragraphs (i) and (ii). Such determination shall be made (1)
         by the Administrative Trustees by a majority vote of a Quorum
         consisting of such Administrative Trustees who were not parties to such
         action, suit or proceeding, (2) if such a Quorum is not obtainable, or,
         even if obtainable, if a Quorum of disinterested Administrative
         Trustees so directs, by independent legal counsel in a written opinion,
         or (3) by the Common Security Holder of the Trust.

                  (v) Expenses (including attorneys' fees and expenses) incurred
         by a Company Indemnified Person in defending a civil, criminal,
         administrative or investigative action, suit or proceeding referred to
         in paragraphs (i) and (ii) of this Section 10.4(a) shall be paid by the
         Sponsor in advance of the final disposition of such action, suit or
         proceeding upon receipt of an undertaking by or on behalf of such
         Company Indemnified Person to repay such amount if it shall ultimately
         be determined that he is not entitled to be indemnified by the Sponsor
         as authorized in this Section 10.4(a). Notwithstanding the foregoing,
         no advance shall be made by the Sponsor if a determination is
         reasonably and promptly made (1) by the Administrative Trustees by a
         majority vote of a Quorum of disinterested Administrative Trustees, (2)
         if such a Quorum is not obtainable, or, even if obtainable, if a quorum
         of disinterested Administrative Trustees so directs, by independent
         legal counsel in a written opinion or (3) by the Common Security Holder
         of the Trust, that, based upon the facts known to the Administrative
         Trustees, counsel or the Common Security Holder at the time such
         determination is made, such Company Indemnified Person acted in bad
         faith or in a manner that such Person did not believe to be in or not
         opposed to the best interests of the Trust, or, with respect to any
         criminal proceeding, that such Company Indemnified Person believed or
         had reasonable cause to believe his conduct was unlawful. In no event
         shall any advance be made in instances where the Administrative
         Trustees, independent legal counsel or Common Security Holder
         reasonably determine that such person deliberately breached his duty to
         the Trust or its Common or Preferred Security Holders.

                  (vi) The indemnification and advancement of expenses provided
         by, or granted pursuant to, the other paragraphs of this Section
         10.4(a) shall not be deemed exclusive of any other rights to which
         those seeking indemnification and advancement of expenses may be
         entitled under any agreement, vote of stockholders or disinterested
         directors of the Sponsor or Preferred Security Holders of the Trust or
         otherwise, both as to action in his official capacity and as to action
         in another capacity while holding such office. All

                                       48
<PAGE>   55
         rights to indemnification under this Section 10.4(a) shall be deemed to
         be provided by a contract between the Sponsor and each Company
         Indemnified Person who serves in such capacity at any time while this
         Section 10.4(a) is in effect. Any repeal or modification of this
         Section 10.4(a) shall not affect any rights or obligations then
         existing.

                  (vii) The Sponsor or the Trust may purchase and maintain
         insurance on behalf of any Person who is or was a Company Indemnified
         Person against any liability asserted against him and incurred by him
         in any such capacity, or arising out of his status as such, whether or
         not the Sponsor would have the power to indemnify him against such
         liability under the provisions of this Section 10.4(a).

                  (viii) For purposes of this Section 10.4(a), references to
         "the Trust" shall include, in addition to the resulting or surviving
         entity, any constituent entity (including any constituent of a
         constituent) absorbed in a consolidation or merger, so that any person
         who is or was a director, trustee, officer or employee of such
         constituent entity, or is or was serving at the request of such
         constituent entity as a director, trustee, officer, employee or agent
         of another entity, shall stand in the same position under the
         provisions of this Section 10.4(a) with respect to the resulting or
         surviving entity as he would have with respect to such constituent
         entity if its separate existence had continued.

                  (ix) The indemnification and advancement of expenses provided
         by, or granted pursuant to, this Section 10.4(a) shall, unless
         otherwise provided when authorized or ratified, continue as to a Person
         who has ceased to be a Company Indemnified Person and shall inure to
         the benefit of the heirs, executors and administrators of such a
         person.

         (b) The Sponsor agrees to indemnify the (i) Property Trustee, (ii) the
Delaware Trustee, (iii) any Affiliate of the Property Trustee and the Delaware
Trustee, and (iv) any officers, directors, shareholders, members, partners,
employees, representatives, custodians, nominees or agents of the Property
Trustee and the Delaware Trustee (each of the Persons in (i) through (iv) being
referred to as a "Fiduciary Indemnified Person") for, and to hold each Fiduciary
Indemnified Person harmless against, any and all loss, liability, damage, claim
or expense including taxes (other than taxes based on the income of such
Fiduciary Indemnified Person) incurred without negligence, willful misconduct or
bad faith on its part, arising out of or in connection with the acceptance or
administration of the trust or trusts hereunder, including the costs and
expenses (including reasonable legal fees and expenses) of defending itself
against or investigating any claim or liability in connection with the exercise
or performance of any of its powers or duties hereunder. With respect to the
Property Trustee, this provision shall not be deemed to modify Section 3.9(b) or
the Trust Indenture Act. The obligation to indemnify as set forth in this
Section 10.4(b) shall survive the resignation or removal of the Property Trustee
or the Delaware Trustee and the satisfaction and discharge of this Agreement.

SECTION 10.5      Outside Businesses.

         Any Covered Person, the Sponsor, the Delaware Trustee and the Property
Trustee (subject to Section 5.3(c)) may engage in or possess an interest in
other business ventures of any nature or description, independently or with
others, similar or dissimilar to the business of the Trust, and the Trust and
the Holders of Securities shall have no rights by virtue of this

                                       49
<PAGE>   56
Agreement in and to such independent ventures or the income or profits derived
therefrom, and the pursuit of any such venture, even if competitive with the
business of the Trust, shall not be deemed wrongful or improper. No Covered
Person, the Sponsor, the Delaware Trustee, or the Property Trustee shall be
obligated to present any particular investment or other opportunity to the Trust
even if such opportunity is of a character that, if presented to the Trust,
could be taken by the Trust, and any Covered Person, the Sponsor, the Delaware
Trustee and the Property Trustee shall have the right to take for its own
account (individually or as a partner or fiduciary) or to recommend to others
any such particular investment or other opportunity. Any Covered Person, the
Delaware Trustee and the Property Trustee may engage or be interested in any
financial or other transaction with the Sponsor or any Affiliate of the Sponsor,
or may act as depositary for, trustee or agent for, or act on any committee or
body of holders of, securities or other obligations of the Sponsor or its
Affiliates.

                                   ARTICLE XI
                                   ACCOUNTING

SECTION 11.1      Fiscal Year.

         The fiscal year ("Fiscal Year") of the Trust shall be the calendar
year, or such other year as is required by the Code.

SECTION 11.2      Certain Accounting Matters.

         (a) At all times during the existence of the Trust, the Administrative
Trustees shall keep, or cause to be kept, full books of account, records and
supporting documents, which shall reflect in reasonable detail, each transaction
of the Trust. The books of account shall be maintained on the accrual method of
accounting, in accordance with generally accepted accounting principles,
consistently applied. The Trust shall use the accrual method of accounting for
United States Federal income tax purposes. The books of account and the records
of the Trust shall be examined by and reported upon as of the end of each Fiscal
Year of the Trust by a firm of independent certified public accountants selected
by the Administrative Trustees.

         (b) The Administrative Trustees shall cause to be prepared and
delivered to each of the Holders of Securities, within 90 days after the end of
each Fiscal Year of the Trust, annual financial statements of the Trust,
including a balance sheet of the Trust as of the end of such Fiscal Year, and
the related statements of income or loss.

         (c) The Administrative Trustees shall cause to be duly prepared and
delivered to each of the Holders of Securities, any annual United States Federal
income tax information statement, required by the Code, containing such
information with regard to the Securities held by each Holder as is required by
the Code and the Treasury Regulations. Notwithstanding any right under the Code
to deliver any such statement at a later date, the Administrative Trustees shall
endeavor to deliver all such information statements within 30 days after the end
of each Fiscal Year of the Trust.

                                       50
<PAGE>   57
         (d) The Administrative Trustees shall cause to be duly prepared and
filed with the appropriate taxing authority, an annual United States Federal
income tax return, on a Form 1041 or such other form required by United States
Federal income tax law, and any other annual income tax returns required to be
filed by the Administrative Trustees on behalf of the Trust with any state or
local taxing authority.

SECTION 11.3      Banking.

         The Trust shall maintain one or more bank accounts in the name and for
the sole benefit of the Trust; provided, however, that all payments of funds in
respect of the Debentures held by the Property Trustee shall be made directly to
the Property Trustee Account and no other funds of the Trust shall be deposited
in the Property Trustee Account. The sole signatories for such accounts shall be
designated by the Administrative Trustees; provided, however, that the Property
Trustee shall designate the signatories for the Property Trustee Account.

SECTION 11.4      Withholding.

         The Trust and the Administrative Trustees, on behalf of the Trust,
shall comply with all withholding requirements under United States Federal,
state and local law. The Administrative Trustees, on behalf of the Trust, shall
request, and the Holders shall provide to the Trust, such forms or certificates
as are necessary to establish an exemption from withholding with respect to each
Holder, and any representations and forms as shall reasonably be requested by
the Administrative Trustees to assist them in determining the extent of, and in
fulfilling, the Trust's withholding obligations. The Administrative Trustees
shall file required forms with applicable jurisdictions and, unless an exemption
from withholding is properly established by a Holder, shall remit amounts
withheld with respect to the Holder to applicable jurisdictions. To the extent
that the Trust is required to withhold and pay over any amounts to any authority
with respect to Distributions or allocations to any Holder, the amount withheld
shall be deemed to be a Distribution in the amount of the withholding to the
Holder. In the event of any claim of excess withholding, Holders shall be
limited to an action against the applicable jurisdiction. If the amount required
to be withheld was not withheld from actual Distributions made, the Trust may
reduce subsequent Distributions by the amount of such withholding.

                                  ARTICLE XII
                             AMENDMENTS AND MEETINGS

SECTION 12.1      Amendments.

         (a) Except as otherwise provided in this Agreement or by any applicable
terms of the Securities, this Agreement may only be amended by a written
instrument approved and executed by:

                  (i) the Sponsor and the Administrative Trustees (or, if there
         are more than two Administrative Trustees, a majority of the
         Administrative Trustees);

                                       51
<PAGE>   58
                  (ii) if the amendment affects the rights, powers, duties,
         obligations or immunities of the Property Trustee, the Property
         Trustee; and

                  (iii) if the amendment affects the rights, powers, duties,
         obligations or immunities of the Delaware Trustee, the Delaware
         Trustee.

         (b) No amendment shall be made, and any such purported amendment shall
be void and ineffective:

                  (i) unless, in the case of any proposed amendment, the
         Property Trustee shall have first received an Officers' Certificate
         from each of the Trust and the Sponsor that such amendment is permitted
         by, and conforms to, the terms of this Agreement (including the terms
         of the Securities);

                  (ii) unless, in the case of any proposed amendment which
         affects the rights, powers, duties, obligations or immunities of the
         Property Trustee, the Property Trustee shall have first received:

                           (A) an Officers' Certificate from each of the Trust
                  and the Sponsor that such amendment is permitted by, and
                  conforms to, the terms of this Agreement (including the terms
                  of the Securities); and

                           (B) an opinion of counsel (who may be counsel to the
                  Sponsor or the Trust) that such amendment is permitted by, and
                  conforms to, the terms of this Agreement (including the terms
                  of the Securities) and that all conditions precedent to the
                  execution and delivery of such amendment have been satisfied;
                  and

                  (iii) to the extent the result of such amendment would:

                           (A) cause the Trust to fail to be classified for
                  purposes of United States Federal income taxation as a grantor
                  trust;

                           (B) reduce or otherwise adversely affect the powers
                  of the Property Trustee in contravention of the Trust
                  Indenture Act; or

                           (C) cause the Trust to be deemed to be an Investment
                  Company required to be registered under the Investment Company
                  Act.

         (c) At such time after the Trust has issued any Securities that remain
outstanding, any amendment that would adversely affect the rights, privileges or
preferences of any Holder of the Securities may be effected only with such
additional requirements as may be set forth in the terms of such Securities;
provided, however, that, without the consent of each Holder of the Securities,
this Agreement may not be amended to (i) change the Distribution rate (or manner
of calculation of the Distribution rate), amount, timing or currency or
otherwise adversely affect the method of any required payment, (ii) change the
purposes of the Trust, (iii) authorize the issuance of any additional beneficial
interests in the Trust, (iv) change the redemption provisions, (v) change the
conditions precedent for the Sponsor to elect to dissolve the Trust and

                                       52
<PAGE>   59
distribute the Debentures to the Holders of the Securities, (vi) change the
Liquidation Distribution or other provisions relating to the distribution of
amounts payable upon the dissolution and liquidation of the Trust, (vii) affect
the limited liability of any Holder of the Securities or (viii) restrict the
right of a Holder of the Securities to institute suit for the enforcement of any
required payment on or after the due date therefor (or in the case of
redemption, on the Redemption Date).

         (d) Section 9.1(c) and this Section 12.1 shall not be amended without
the consent of all of the Holders of the Securities.

         (e) Article IV shall not be amended without the consent of the Holders
of a Majority in Liquidation Amount of the Common Securities.

         (f) The rights of the Holders of the Common Securities under Article V
to increase or decrease the number of, and to appoint and remove, Trustees shall
not be amended without the consent of the Holders of a Majority in Liquidation
Amount of the Common Securities.

         (g) Notwithstanding Section 12.1(c), this Agreement may be amended by
the Sponsor and the Trustees without the consent of the Holders of the
Securities to:

                  (i) cure any ambiguity, correct or supplement any provision in
         this Agreement that may be inconsistent with any other provision of
         this Agreement or make any other provisions with respect to matters or
         questions arising under this Agreement not inconsistent with any other
         provisions of this Agreement;

                  (ii) modify, eliminate or add to any provisions of this
         Agreement to such extent as shall be necessary to ensure that the Trust
         will be classified for United States Federal income tax purposes as a
         grantor trust at all times that any Securities are outstanding or to
         ensure that the Trust will not be required to register as an Investment
         Company under the Investment Company Act;

provided, however, that, in each case, such action shall not adversely affect in
any material respect the interests of the Holders of the Securities, and any
such amendments of this Agreement shall become effective when notice thereof is
given to the Holders of the Securities.

SECTION 12.2 Meetings of the Holders of Securities; Action by Written Consent.

         (a) Meetings of the Holders of any class of Securities may be called at
any time by the Administrative Trustees (or as provided in the terms of the
Securities) to consider and act on any matter on which Holders of such class of
Securities are entitled to act under the terms of this Agreement, the terms of
the Securities or the rules of any stock exchange or quotation system or market
on which the Preferred Securities are listed or admitted for trading. The
Administrative Trustees shall call a meeting of the Holders of such class if
directed to do so by the Holders of at least 10% in Liquidation Amount of the
Securities of such class. Such direction shall be given by delivering to the
Administrative Trustees one or more notices in a writing stating that the
signing Holders of Securities wish to call a meeting and indicating the general
or

                                       53
<PAGE>   60
specific purpose for which the meeting is to be called. Any Holders of
Securities calling a meeting shall specify in writing the security certificates
held by the Holders of Securities exercising the right to call a meeting and
only those Securities specified shall be counted for purposes of determining
whether the required percentage set forth in the second sentence of this
paragraph has been met.

         (b) Whenever a vote, consent or approval of the Holders of Securities
is permitted or required under this Agreement or the rules of any stock exchange
or quotation system or market on which the Preferred Securities are listed or
admitted for trading, such vote, consent or approval may be given at a meeting
of the Holders of Securities. Any action that may be taken at a meeting of the
Holders of Securities may be taken without a meeting if a consent in writing
setting forth the action so taken is signed by the Holders of Securities owning
not less than the minimum amount of Securities in Liquidation Amount that would
be necessary to authorize or take such action at a meeting at which all Holders
of Securities having a right to vote thereon were present and voting. Prompt
notice of the taking of action without a meeting shall be given to the Holders
of Securities entitled to vote who have not consented in writing.

         (c) Except to the extent otherwise provided in the terms of the
Securities, the following provisions shall apply to meetings of Holders of
Securities:

                  (i) notice of any such meeting shall be given to all the
         Holders of Securities having a right to vote thereat at least seven
         days and not more than 60 days before the date of such meeting. The
         Administrative Trustees may specify that any written ballot submitted
         to the Security Holders for the purpose of taking any action without a
         meeting shall be returned to the Trust within the time specified by the
         Administrative Trustees;

                  (ii) each Holder of a Security may authorize any Person to act
         for it by proxy on all matters in which a Holder of Securities is
         entitled to participate, including waiving notice of any meeting, or
         voting or participating at a meeting. No proxy shall be valid after the
         expiration of eleven months from the date thereof unless otherwise
         provided in the proxy. Every proxy shall be revocable at the pleasure
         of the Holder of Securities executing it. Except as otherwise provided
         herein, all matters relating to the giving, voting or validity of
         proxies shall be governed by the General Corporation Law of the State
         of Delaware relating to proxies, and judicial interpretations
         thereunder, as if the Trust were a Delaware corporation and the Holders
         of the Securities were stockholders of a Delaware corporation;

                  (iii) each meeting of the Holders of the Securities shall be
         conducted by the Administrative Trustees or by such other Person that
         the Administrative Trustees may designate; and

                  (iv) unless the Business Trust Act, this Agreement, the terms
         of the Securities, the Trust Indenture Act or the listing rules of any
         stock exchange or quotation system or market on which the Preferred
         Securities are then listed or trading, otherwise provides, the
         Administrative Trustees, in their sole discretion, shall establish all
         other provisions relating to meetings of Holders of Securities,
         including notice of the time, place or purpose of any meeting at which
         any matter is to be voted on by any Holders of

                                       54
<PAGE>   61
         Securities, waiver of any such notice, action by consent without a
         meeting, the establishment of a record date, quorum requirements,
         voting in person or by proxy or any other matter with respect to the
         exercise of any such right to vote.

                                  ARTICLE XIII
                       REPRESENTATIONS OF PROPERTY TRUSTEE
                              AND DELAWARE TRUSTEE

SECTION 13.1      Representations and Warranties of Property Trustee.

         The Trustee that acts as initial Property Trustee represents and
warrants to the Trust and to the Sponsor at the date of this Agreement, and each
Successor Property Trustee represents and warrants, as applicable, to the Trust
and the Sponsor at the time of the Successor Property Trustee's acceptance of
its appointment as Property Trustee that:

         (a) the Property Trustee is a banking corporation, a national banking
association or a bank or trust company, duly organized, validly existing and in
good standing under the laws of the United States or a State of the United
States, as the case may be, with corporate power and authority to execute and
deliver, and to carry out and perform its obligations under the terms of, this
Agreement;

         (b) the execution, delivery and performance by the Property Trustee of
the Agreement have been duly authorized by all necessary corporate action on the
part of the Property Trustee. The Agreement has been duly executed and delivered
by the Property Trustee under New York law and constitutes a legal, valid and
binding obligation of the Property Trustee, enforceable against it in accordance
with its terms, subject to applicable bankruptcy, reorganization, moratorium,
insolvency, and other similar laws affecting creditors' rights generally and to
general principles of equity and the discretion of the court (regardless of
whether the enforcement of such remedies is considered in a proceeding in equity
or at law);

         (c) the execution, delivery and performance of this Agreement by the
Property Trustee do not conflict with or constitute a breach of the charter or
by-laws of the Property Trustee; and

         (d) no consent, approval or authorization of, or registration with or
notice to, any federal or New York State banking authority is required for the
execution, delivery or performance by the Property Trustee of this Agreement.

SECTION 13.2      Representations and Warranties of Delaware Trustee.

         The Trustee that acts as initial Delaware Trustee represents and
warrants to the Trust and to the Sponsor at the date of this Agreement, and each
Successor Delaware Trustee represents and warrants to the Trust and the Sponsor
at the time of the Successor Delaware Trustee's acceptance of its appointment as
Delaware Trustee that:

         (a) the Delaware Trustee is a banking corporation, a national banking
association or a bank or trust company, duly organized, validly existing and in
good standing under the laws

                                       55
<PAGE>   62
of the United States or the State of Delaware, as the case may be, with
corporate power and authority to execute and deliver, and to carry out and
perform its obligations under the terms of, this Agreement;

         (b) the execution, delivery and performance by the Delaware Trustee of
this Agreement have been duly authorized by all necessary corporate action on
the part of the Delaware Trustee. This Agreement has been duly executed and
delivered by the Delaware Trustee under Delaware law and constitutes a legal,
valid and binding obligation of the Delaware Trustee, enforceable against it in
accordance with its terms, subject to applicable bankruptcy, reorganization,
moratorium, insolvency, and other similar laws affecting creditors' rights
generally and to general principles of equity and the discretion of the court
(regardless of whether the enforcement of such remedies is considered in a
proceeding in equity or at law);

         (c) the execution, delivery and performance of this Agreement by the
Delaware Trustee do not conflict with or constitute a breach of the charter or
by-laws of the Delaware Trustee;

         (d) no consent, approval or authorization of, or registration with or
notice to, any Federal or Delaware banking authority governing the trust powers
of the Delaware Trustee is required for the execution, delivery or performance
by the Delaware Trustee of this Agreement; and

         (e) the Delaware Trustee is a natural person who is a resident of the
State of Delaware or, if not a natural person, an entity which has its principal
place of business in the State of Delaware, and is a Person that satisfies for
the Trust Section 3807(a) of the Business Trust Act.

                                  ARTICLE XIV
                                  MISCELLANEOUS

SECTION 14.1      Notices.

         All notices provided for in this Agreement shall be in writing, duly
signed by the party giving such notice, and shall be delivered, telecopied or
mailed by first class mail, as follows:

         (a) if given to the Trust, in care of the Administrative Trustees at
the Trust's mailing address set forth below (or such other address as the Trust
may give notice of to the Holders of the Securities):

                     Hercules Trust VI
                     c/o Hercules Incorporated
                     Hercules Plaza
                     1313 North Market Street
                     Wilmington, Delaware  19894-0001

                                       56
<PAGE>   63
                     Attention:  Israel J. Floyd
                     Telephone: (302) 594-5000
                     Telecopier: (302) 594-5210

         (b) if given to the Delaware Trustee, at the mailing address set forth
below (or such other address as Delaware Trustee may give notice of to the
Holders of the Securities):

                     Chase Manhattan Bank Delaware
                     1201 Market Street
                     Wilmington, Delaware  19801
                     Attention:  Corporate Trust Department
                     Telephone:  (302) 984-3372
                     Telecopier: (302) 428-4903

         (c) if given to the Property Trustee, at the Property Trustee's mailing
address set forth below (or such other address as the Property Trustee may give
notice of to the Holders of the Securities):

                     The Chase Manhattan Bank
                     c/o Chase Manhattan Trust Company, National Association
                     One Liberty Place, 52nd Floor
                     1650 Market Street
                     Philadelphia, Pennsylvania  19103
                     Attention:  Capital Markets Fiduciary Services
                     Telephone:  (215) 988-1317
                     Telecopier: (215) 972-8372

         (d) if given to the Holder of the Common Securities, at the mailing
address of the Sponsor set forth below (or such other address as the Holder of
the Common Securities may give notice to the Trust):

                     Hercules Incorporated
                     Hercules Plaza
                     1313 North Market Street
                     Wilmington, Delaware 19894-0001

                     Attention:  Vice-President and Treasurer and
                                 Corporate Secretary of the Sponsor
                     Telephone:  (302) 594-5000
                     Telecopier: (302) 594-5210

         (e) if given to any other Holder, at the address set forth on the books
and records of the Trust.

                                       57
<PAGE>   64
         All such notices shall be deemed to have been given when received in
person, telecopied with receipt confirmed, or mailed by first class mail,
postage prepaid except that if a notice or other document is refused delivery or
cannot be delivered because of a changed address of which no notice was given,
such notice or other document shall be deemed to have been delivered on the date
of such refusal or inability to deliver.

SECTION 14.2      Governing Law.

         This Agreement and the rights of the parties hereunder shall be
governed by and construed in accordance with the laws of the State of Delaware
and all rights and remedies shall be governed by such laws without regard to
principles of conflict of laws, except that the rights, limitations of rights,
obligations, duties and immunities of the Property Trustee shall be governed by
and construed in accordance with the laws of the State of New York.

SECTION 14.3      Intention of the Parties.

         It is the intention of the parties hereto that the Trust be classified
for United States Federal income tax purposes as a grantor trust. The provisions
of this Agreement shall be interpreted to further this intention of the parties.

SECTION 14.4      Headings.

         The Table of Contents, Cross-Reference Table and Headings contained in
this Agreement are inserted for convenience of reference only and do not affect
the interpretation of this Agreement or any provision hereof.

SECTION 14.5      Successors and Assigns.

         Whenever in this Agreement any of the parties hereto is named or
referred to, the successors and assigns of such party shall be deemed to be
included, and all covenants and agreements in this Agreement by the Sponsor and
the Trustees shall bind and inure to the benefit of their respective successors
and assigns, whether so expressed.

SECTION 14.6      Partial Enforceability.

         If any provision of this Agreement, or the application of such
provision to any Person or circumstance, shall be held invalid, the remainder of
this Agreement, or the application of such provision to Persons or circumstances
other than those to which it is held invalid, shall not be affected thereby.

SECTION 14.7      Counterparts.

         This Agreement may contain more than one counterpart of the signature
page and this Agreement may be executed by the affixing of the signature of each
of the Trustees to one of such counterpart signature pages. All of such
counterpart signature pages shall be read as though one, and they shall have the
same force and effect as though all of the signers had signed a single signature
page.

                                       58
<PAGE>   65
         IN WITNESS WHEREOF, the undersigned have caused this Amended and
Restated Trust Agreement to be executed as of the day and year first above
written.

                                Michael J. Scott, not in his individual capacity
                                but solely as Administrative Trustee of the
                                Trust

                                ________________________________________________

                                Stuart C. Shears, not in his individual capacity
                                but solely as Administrative Trustee of the
                                Trust

                                ________________________________________________

                                Israel J. Floyd, not in his individual capacity
                                but solely as Administrative Trustee of the
                                Trust

                                ________________________________________________

                                Chase Manhattan Bank Delaware, not in its
                                individual capacity but solely as Delaware
                                Trustee of the Trust

                                By:_____________________________________________
                                   Name:
                                   Title:

                                The Chase Manhattan Bank, not in its individual
                                capacity but solely as Property Trustee of the
                                Trust

                                By:_____________________________________________
                                   Name:
                                   Title:

                                       59
<PAGE>   66
                                Hercules Incorporated,
                                as Sponsor of the Trust

                                By:_____________________________________________
                                   Name:
                                   Title:

                                       60
<PAGE>   67
                                     ANNEX I

                                    TERMS OF
                       FLOATING RATE PREFERRED SECURITIES
                         FLOATING RATE COMMON SECURITIES

         Pursuant to Section 7.1 of the Amended and Restated Trust Agreement of
the Trust, dated as of December 23, 1999 (as amended from time to time, the
"Agreement"), the designation, rights, privileges, restrictions, preferences and
other terms and provisions of the Floating Rate Preferred Securities (the
"Preferred Securities") and the Floating Rate Common Securities (the "Common
Securities," and together with the Preferred Securities, the "Securities") are
set forth below (each capitalized term used but not defined herein has the
meaning set forth in the Agreement or, if not defined in such Agreement, as
defined in the Indenture):

         1. Designation and Number.

         (a) Preferred Securities. Up to and including 170,000 Preferred
Securities of the Trust, with an aggregate liquidation amount with respect to
the assets of the Trust of one hundred and seventy million dollars
($170,000,000), and with a Liquidation Amount with respect to the assets of the
Trust of $1,000 per security, are hereby designated for the purposes of
identification only as "Floating Rate Preferred Securities". The Trust may
issue, without the consent of the Holders of the Preferred Securities,
additional Preferred Securities having the same terms (other than the date of
issuance and the date on which Distributions begin to accumulate) as the
Preferred Securities issued at the Closing Time so as to form a single series
with the Preferred Securities theretofore issued. The certificates evidencing
the Preferred Securities shall be substantially in the form of Exhibit A-1 to
the Agreement.

         (b) Common Securities. Up to and including 5,258 Common Securities of
the Trust with an aggregate Liquidation Amount with respect to the assets of the
Trust of five million two hundred fifty eight thousand dollars ($5,258,000), and
with a Liquidation Amount with respect to the assets of the Trust of $1,000 per
security, are hereby designated for the purposes of identification only as
"Floating Rate Common Securities". If the Trust issued additional Preferred
Securities pursuant to the second sentence of Section 1(a), then the Trust will
issue additional Common Securities having the same terms (other than the date of
issuance and the date on which Distribution begin to accumulate) as the Common
Securities issued at the Closing Time so as to form a single series with the
Common Securities theretofore issued. The certificate evidencing the Common
Securities shall be substantially in the form of Exhibit A-2 to the Agreement.

         2. Distributions.

         (a) Distributions will be payable at the rate per annum, reset
quarterly, equal to LIBOR (as defined below) plus 245 basis points (2.45%) of
the $1,000 Liquidation Amount per Security (the "Distribution Rate").
Distributions in arrears for more than one quarterly

                                      I-1
<PAGE>   68
period will bear additional distributions thereon compounded quarterly at the
applicable periodic Distribution Rate (to the extent permitted by applicable
law). The term "Distributions", as used herein, includes any such additional
distributions unless otherwise stated. A Distribution is payable only to the
extent that payments are made in respect of the Debentures held by the Property
Trustee and to the extent the Property Trustee has funds legally available
therefor.

         (b) Distributions on the Securities will be cumulative, will be payable
quarterly in arrears on March 29, 2000, June 29, 2000, September 29, 2000 and
December 29, 2000 (each, a "Distribution Date"), will accumulate from and
including the most recent date to which Distributions have been paid or, if no
Distributions have been paid, from and including December 23, 1999, to but
excluding the related Distribution Date (a "Distribution Period").

         (c) The amount of Distributions payable for any Distribution Period
will be computed on the basis of the actual number of days in such Distribution
Period and a year of 360 days. If a Distribution Date is not a Business Day,
then such Distribution Date will be postponed to the next succeeding Business
Day. However, if the next succeeding Business Day is in the next succeeding
calendar month, such Distribution Date will be the immediately preceding
Business Day.

         (d) Distributions on a Distribution Date will be payable to the Holders
thereof as they appear on the books and records of the Trust on the day
immediately preceding such Distribution Date. If the Preferred Securities are
ever issued in the form of Definitive Preferred Securities, the record date for
the payment of Distributions shall be the 15th day of the calendar month in
which the Distribution Date occurs, even if that day is not a Business Day. The
relevant record dates for the Common Securities shall be the same as the record
dates for the Preferred Securities. Distributions payable on any Securities that
are not punctually paid or duly provided for on any Distribution Date, as a
result of the Debenture Issuer having failed to make a payment under the
Debentures, will cease to be payable to the Holder on the relevant record date,
and such defaulted Distributions will instead be payable to the Person in whose
name such Securities are registered on the Special Record Date or other
specified date for the Debentures determined in accordance with the Indenture.

         (e) The "Calculation Agent" shall be The Chase Manhattan Bank or any
successor appointed by the Sponsor and will calculate the Distribution Rate for
each Distribution Period based on LIBOR determined as of two London Business
Days prior to the first day of such Distribution Period (each, a "Determination
Date"). "LIBOR" means, with respect to a Distribution Period relating to a
Distribution Date (in the following order of priority):

                  (1) the rate (expressed as a percentage per annum) for
Eurodollar deposits having a three-month maturity that appears on Telerate Page
3750 as of 11:00 a.m. (London time) on the applicable Determination Date;

                  (2) if such rate does not appear on Telerate Page 3750 as of
11:00 a.m. (London time) on the applicable Determination Date, the Calculation
Agent will request the principal London offices of four leading banks in the
London interbank market as selected by the Calculation Agent in consultation
with the Sponsor to provide such banks' offered quotations (expressed as
percentages per annum) to prime banks in the London interbank market for

                                      I-2
<PAGE>   69
Eurodollar deposits having a three-month maturity as of 11:00 a.m. (London time)
on such Determination Date, and if at least two quotations are provided, LIBOR
will be the arithmetic mean of such quotations (rounded upwards if necessary to
the fifth decimal place);

                  (3) if fewer than two such quotations are provided as
requested in clause (2) above, the Calculation Agent will request four major New
York City banks selected by the Calculation Agent in consultation with the
Sponsor to provide such banks' offered quotations (expressed as percentages per
annum) to leading European banks for loans in Eurodollars as of 11:00 a.m. (New
York City time) on such Determination Date, and if at least two quotations are
provided, LIBOR will be the arithmetic mean of such quotations (rounded upwards
if necessary to the fifth decimal place); and

                  (4) if fewer than two such quotations are provided as
requested in clause (3) above, LIBOR will be LIBOR as determined on the
preceding Determination Date.

         The Distribution Rate for any Distribution Period will at no time be
higher than the maximum rate then permitted by New York law, as the same may be
modified by United States law.

         Absent manifest error, the Calculation Agent's determination of LIBOR
and its calculation of the applicable Distribution Rate for each Distribution
Period will be final and binding.

         (f) As long as no Event of Default has occurred and is continuing under
the Indenture, the Debenture Issuer has the right under the Indenture to defer
payments of interest on the Debentures by extending the interest payment period
at any time and from time to time (each period as to which interest payments
have been deferred is referred to herein as an "Extension Period"), provided
that an Extension Period must end on an Interest Payment Date for the Debentures
and may not extend beyond December 29, 2000 (the "Stated Maturity Date"). As a
consequence of such deferral, Distributions on the Securities will also be
deferred during an Extension Period. Despite such deferral, quarterly
Distributions will continue to accumulate with additional interest thereon (to
the extent permitted by applicable law but not at a rate greater than the rate
at which interest is then accruing on the Debentures) at the Distribution Rate
then in effect, compounded quarterly during any Extension Period. Prior to the
termination of an Extension Period, the Debenture Issuer may further defer
payments of interest by further extending such Extension Period; provided that
an Extension Period, together with all such previous and further extensions, may
not extend beyond the Stated Maturity Date. At the end of an Extension Period,
all accumulated and unpaid Distributions (but only to the extent payments are
made in respect of the Debentures held by the Property Trustee and to the extent
the Property Trustee has funds legally available therefor) will be payable to
the Holders as they appear on the books and records of the Trust on the record
date immediately preceding the end of the Extension Period. Upon the termination
of any Extension Period (or any extension thereof) and the payment of all
amounts then due, the Debenture Issuer may commence a new Extension Period,
subject to the foregoing requirements.

                                      I-3
<PAGE>   70
         (g) In the event that there is any money or other property held by or
for the Trust that is not accounted for hereunder, such property shall be
distributed on a Pro Rata (as defined herein) basis among the Holders of the
Securities.

         3. Liquidation Distribution Upon Dissolution.

         In the event of any dissolution of the Trust, the Trust shall be
liquidated by the Administrative Trustees as expeditiously as the Administrative
Trustees determine to be possible by distributing, after satisfaction of
liabilities to creditors of the Trust as provided by applicable law, to the
Holders of the Securities a Like Amount (as defined below) of the Debentures,
unless such distribution is determined by the Property Trustee not to be
practicable, in which event such Holders will be entitled to receive out of the
assets of the Trust legally available for distribution to Holders, after
satisfaction of liabilities to creditors of the Trust as provided by applicable
law, an amount equal to the aggregate of the Liquidation Amount of $1,000 per
Security plus accumulated and unpaid Distributions thereon to the date of
payment (such amount is referred to herein as the "Liquidation Distribution").

         "Like Amount" means (i) with respect to a redemption of the Securities,
Securities having a Liquidation Amount equal to the principal amount of
Debentures to be paid in accordance with their terms and (ii) with respect to a
distribution of Debentures upon the dissolution of the Trust, Debentures having
a principal amount equal to the Liquidation Amount of the Securities of the
Holder to whom such Debentures are distributed.

         If, upon any such liquidation, the Liquidation Distribution can be paid
only in part because the Trust has insufficient assets legally available to pay
in full the aggregate Liquidation Distribution, then the amounts payable
directly by the Trust on the Securities shall be paid on a Pro Rata basis.

         4. Redemption and Distribution.

         (a) Upon the repayment of the Debentures on the Stated Maturity Date,
the proceeds from such repayment shall be simultaneously applied by the Property
Trustee to redeem a Like Amount of the Securities at the Redemption Price (as
defined below). Holders will be given not less than 30 nor more than 60 days'
prior written notice of such redemption. Any redemption of Securities shall be
made, and the Redemption Price shall be payable, on the Redemption Date, and
only to the extent that the Trust has funds legally available for the payment
thereof.

         (b) The "Redemption Price" shall mean a price equal to 100% of the
Liquidation Amount of the Securities to be redeemed plus accumulated and unpaid
Distributions thereon, if any, to the date of redemption.

         (c) On and from the date fixed by the Administrative Trustees for any
distribution of Debentures and liquidation of the Trust: (i) the Securities will
no longer be deemed to be outstanding, (ii) the Clearing Agency or its nominee
(or any successor Clearing Agency or its nominee), as the Holder of the
Preferred Securities, will receive a registered global certificate or
certificates representing the Debentures to be delivered upon such distribution
and

                                      I-4
<PAGE>   71
(iii) any certificates representing Securities not held by the Clearing Agency
or its nominee (or any successor Clearing Agency or its nominee) will be deemed
to represent beneficial interests in Debentures until such certificates are
presented to the Debenture Issuer or its agent for transfer or reissue.

         (a) (d) The procedure with respect to redemptions or distributions of
Debentures shall be as follows:

                  (i) Notice of any redemption of, or notice of distribution of
         Debentures in exchange for, the Securities (a "Redemption/Distribution
         Notice") will be given by an Administrative Trustee on behalf of the
         Trust by mail to each Holder of Securities to be redeemed or exchanged
         not fewer than 30 nor more than 60 days before the date fixed for
         redemption or exchange thereof which, in the case of a redemption, will
         be the date fixed for redemption of the Debentures. For purposes of the
         calculation of the date of redemption or exchange and the dates on
         which notices are given pursuant to this Section 4(f)(i), a Redemption/
         Distribution Notice shall be deemed to be given on the day such notice
         is first mailed by first-class mail, postage prepaid, to Holders of
         Securities. Each Redemption/Distribution Notice shall be addressed to
         the Holders of Securities at the address of each such Holder appearing
         in the books and records of the Trust. No defect in the Redemption/
         Distribution Notice or in the mailing of either thereof with respect to
         any Holder shall affect the validity of the redemption or exchange
         proceedings with respect to any other Holder.

                  (ii) In the event that fewer than all the outstanding
         Securities are to be redeemed, the Securities to be redeemed shall be
         redeemed on a Pro Rata basis from each Holder of Preferred Securities,
         it being understood that, in respect of Preferred Securities registered
         in the name of and held of record by the Clearing Agency or its nominee
         (or any successor Clearing Agency or its nominee) or any nominee, the
         distribution of the proceeds of such redemption will be made to the
         Clearing Agency and disbursed by such Clearing Agency in accordance
         with the procedures applied by such agency or nominee.

                  (iii) If Securities are to be redeemed and the Trust gives a
         Redemption/Distribution Notice (which notice will be irrevocable), then
         (A) with respect to Global Preferred Securities representing Preferred
         Securities issued in book-entry form, by 12:00 noon, New York City
         time, on the Redemption Date, provided that the Debenture Issuer has
         paid the Property Trustee a sufficient amount of cash in connection
         with the maturity of the Debentures by 10:00 a.m., New York City time,
         on the Stated Maturity Date, the Property Trustee will deposit
         irrevocably with the Clearing Agency or its nominee (or successor
         Clearing Agency or its nominee) funds sufficient to pay the Redemption
         Price with respect to such Preferred Securities and will give the
         Clearing Agency irrevocable instructions and authority to pay the
         Redemption Price to the relevant Participants, and (B) with respect to
         Definitive Preferred Securities and Common Securities, provided that
         the Debenture Issuer has paid the Property Trustee a sufficient amount
         of cash in connection with the maturity of the Debentures, the Property
         Trustee will pay the Redemption Price to the Holders of such Securities
         by check mailed to the address of such Holder appearing on the books
         and records of the Trust on the Redemption Date. If a
         Redemption/Distribution Notice shall have been given and funds

                                      I-5
<PAGE>   72
         deposited as required, then immediately prior to the close of business
         on the date of such deposit, or on the Redemption Date, as applicable,
         Distributions will cease to accumulate on the Securities so called for
         redemption and all rights of Holders of such Securities so called for
         redemption will cease, except the right of the Holders of such
         Securities to receive the Redemption Price, but without interest on
         such Redemption Price, and such Securities shall cease to be
         outstanding.

                  (iv) Payment of accumulated and unpaid Distributions on the
         Redemption Date will be subject to the rights of Holders of Securities
         on the close of business on a record date in respect of a Distribution
         Date occurring on such Redemption Date.

                  (v) If a Redemption Date is not a Business Day, then payment
         of the Redemption Price payable on such date will be made on the next
         succeeding Business Day, and no interest or other payment in respect of
         any such delay will accumulate for the period to but excluding such
         Business Day. If payment of the Redemption Price in respect of any
         Securities is improperly withheld or refused and not paid either by the
         Property Trustee or by the Sponsor as guarantor pursuant to the
         relevant Securities Guarantee, Distributions on such Securities will
         continue to accumulate from the original redemption date to the actual
         date of payment, in which case the actual payment date will be
         considered the Redemption Date for purposes of calculating the
         Redemption Price.

                  (vi) Redemption/Distribution Notices shall be sent by the
         Property Trustee on behalf of the Trust to (A) in respect of the
         Preferred Securities, the Clearing Agency or its nominee (or any
         successor Clearing Agency or its nominee) if the Global Preferred
         Securities have been issued or, if Definitive Preferred Securities have
         been issued, to the Holders thereof, and (B) in respect of the Common
         Securities, to the Sponsor.

                  (vii) Subject to the foregoing and applicable law (including,
         without limitation, United States Federal securities laws and banking
         laws), the Sponsor or any of its subsidiaries may at any time and from
         time to time purchase outstanding Preferred Securities by tender, in
         the open market or by private agreement.

         5. Voting Rights - Preferred Securities.

         (a) Except as provided under Sections 5(b) and 7 and as otherwise
required by law or the Agreement, the Holders of the Preferred Securities will
have no voting rights.

         (b) So long as any Debentures are held by the Property Trustee, the
Trustees shall not (i) direct the time, method and place of conducting any
proceeding with respect to any remedy available to the Debenture Trustee, or
exercise any trust or power conferred upon the Debenture Trustee, with respect
to the Debentures, (ii) waive any past default that is waivable under the
Indenture, (iii) exercise any right to rescind or annul a declaration of
acceleration of the maturity of the principal of the Debentures, or (iv) consent
to any amendment, modification or termination of the Indenture or the Debentures
where such consent shall be required, without, in each case, obtaining (1) the
prior approval of the Holders of a Majority in Liquidation Amount of all
outstanding Preferred Securities; provided, however, that where a consent under
the Indenture would require the consent of each holder of Debentures affected
thereby, no such

                                      I-6
<PAGE>   73
consent shall be given by the Property Trustee without the prior approval of
each Holder of the Preferred Securities and (2) an Opinion of Counsel delivered
to the Trust from tax counsel experienced in such matters to the effect that the
Trust will not be classified as an association taxable as corporation for United
States Federal income tax purposes on account of such action.

         Notwithstanding anything to the contrary contained herein, if an Event
of Default under the Agreement has occurred and is continuing and such event is
attributable to the failure of the Debenture Issuer to pay principal of or
interest on the Debentures on the date such principal or interest is otherwise
payable, then a Holder of Preferred Securities may directly institute a
proceeding against the Debenture Issuer for enforcement of payment to such
Holder of the principal of or interest on a Like Amount of Debentures (a "Direct
Action") on or after the respective due date specified in the Debentures. In
connection with such a Direct Action, (i) the rights of the Common Securities
Holder will be subordinated to the rights of Holders of Preferred Securities
with respect to payments made or required to be made by the Debenture Issuer in
such Direct Action and (ii) the Debenture Issuer shall remain obligated to pay
the principal of or interest on such Debentures, and the Debenture Issuer shall
be subrogated to the rights of such Holder of Preferred Securities to the extent
of any payment made by the Debenture Issuer to such Holder in such Direct
Action.

         Any approval or direction of Holders of Preferred Securities may be
given at a separate meeting of Holders of Preferred Securities convened for such
purpose, at a meeting of all of the Holders of Securities or pursuant to written
consent. The Property Trustees will cause a notice of any meeting at which
Holders of Preferred Securities are entitled to vote to be mailed to each Holder
of record of Preferred Securities. Each such notice will include a statement
setting forth (i) the date of such meeting, (ii) a description of any resolution
proposed for adoption at such meeting on which such Holders are entitled to vote
and (iii) instructions for the delivery of proxies.

         No vote or consent of the Holders of the Preferred Securities will be
required for the Trust to distribute the Debentures in accordance with the
Agreement and these terms of the Securities.

         Notwithstanding that Holders of Preferred Securities are entitled to
vote or consent under any of the circumstances described above, any of the
Preferred Securities that are owned by the Sponsor or any Affiliate of the
Sponsor shall not be entitled to vote or consent and shall, for purposes of such
vote or consent, be treated as if they were not outstanding.

         6. Voting Rights - Common Securities.

         (a) Except as provided under Sections 6(b) and 7 as otherwise required
by law or the Agreement, the Holders of the Common Securities will have no
voting rights.

         (b) So long as any Debentures are held by the Property Trustee, the
Trustees shall not (i) direct the time, method and place of conducting any
proceeding with respect to any remedy available to the Debenture Trustee, or
exercise any trust or power conferred upon the Debenture Trustee, with respect
to the Debentures, (ii) waive any past default that is waivable under the
Indenture, (iii) exercise any right to rescind or annul a declaration of
acceleration of

                                      I-7
<PAGE>   74
the maturity of the principal of the Debentures or (iv) consent to any
amendment, modification or termination of the Indenture or the Debentures where
such consent shall be required, without, in each case, obtaining (1) the prior
approval of the Holders of a Majority in Liquidation Amount of all outstanding
Common Securities; provided, however, that where a consent under the Indenture
would require the consent of each holder of Debentures affected thereby, no such
consent shall be given by the Property Trustee without the prior approval of the
Common Securities Holder and (2) an Opinion of Counsel delivered to the Trust
from tax counsel experienced in such matters to the effect that the Trust will
not be classified as an association taxable as a corporation for United States
Federal income tax purposes on account of such action.

         Notwithstanding anything to the contrary contained herein, if an Event
of Default under the Agreement has occurred and is continuing and such event is
attributable to the failure of the Debenture Issuer to pay principal of or
interest on the Debentures on the date such principal or interest is otherwise
payable, then a Holder of Common Securities may institute a Direct Action
against the Debenture Issuer for enforcement of payment to such Holder of the
principal of or interest on a Like Amount of Debentures on or after the
respective due date specified in the Debentures. In connection with such a
Direct Action, (i) the rights of the Common Securities Holder will be
subordinated to the rights of Holders of Preferred Securities with respect to
payments made or required to be made by the Debenture Issuer in such Direct
Action and (ii) the Debenture Issuer shall remain obligated to pay the principal
of or interest on such Debentures, and the Debenture Issuer shall be subrogated
to the rights of such Holder of Preferred Securities to the extent of any
payment made by the Debenture Issuer to such Holder in such Direct Action.

         Any approval or direction of Holder(s) of Common Securities may be
given at a separate meeting of Holder(s) of Common Securities convened for such
purpose, at a meeting of all of the Holders of Securities or pursuant to written
consent. The Administrative Trustees will cause a notice of any meeting at which
Holder(s) of Common Securities are entitled to vote to be mailed to each Holder
of record of Common Securities. Each such notice will include a statement
setting forth (i) the date of such meeting, (ii) a description of any resolution
proposed for adoption at such meeting on which such Holder(s) are entitled to
vote and (iii) instructions for the delivery of proxies.

         No vote or consent of the Holder(s) of the Common Securities will be
required for the Trust to distribute the Debentures in accordance with the
Agreement and these terms of the Securities.

         7. Amendments to Agreement.

         (b) In addition to the requirements set out in Section 12.1 of the
Agreement, the Agreement may be amended from time to time by the Sponsor and the
Trustees with (i) the consent of Holders of a Majority in Liquidation Amount of
all outstanding Securities, and (ii) receipt by the Trustees of an opinion of
counsel experienced in such matters to the effect that such amendment or the
exercise of any power granted to the Trustees in accordance with such amendment
will not affect the Trust's status as a grantor trust for United States Federal
income tax purposes or the Trust's exemption from status as an Investment
Company under the Investment Company Act; provided, however, that, without the
consent of each Holder of the

                                      I-8
<PAGE>   75
Securities, the Agreement may not be amended to (i) change the Distribution Rate
(or manner of calculation of the Distribution Rate), amount, timing or currency
or otherwise adversely affect the method of any required payment, (ii) change
the purposes of the Trust, (iii) authorize the issuance of any additional
beneficial interests in the Trust, (iv) change the redemption provisions, (v)
change the conditions precedent for the Sponsor to elect to dissolve the Trust
and distribute the Debentures to the Holders of the Securities, (vi) change the
Liquidation Distribution or other provisions relating to the distribution of
amounts payable upon the dissolution and liquidation of the Trust, (vii) affect
the limited liability of any Holder of the Securities or (viii) restrict the
right of a Holder of the Securities to institute suit for the enforcement of any
required payment on or after the due date therefor (or, in the case of
redemption, on the Redemption Date).

         8. Pro Rata.

         A reference herein to any payment, distribution or treatment as being
"Pro Rata" shall mean pro rata to each Holder of Securities according to the
aggregate Liquidation Amount of the Securities held by such Holder in relation
to the aggregate Liquidation Amount of all Securities outstanding unless, in
relation to a payment, an Event of Default under the Agreement has occurred and
is continuing, in which case any funds legally available to make such payment
shall be paid first to each Holder of the Preferred Securities pro rata
according to the aggregate Liquidation Amount of Preferred Securities held by
such Holder relative to the aggregate Liquidation Amount of all Preferred
Securities outstanding, and only after satisfaction of all amounts owed to the
Holders of the Preferred Securities, to each Holder of Common Securities pro
rata according to the aggregate Liquidation Amount of Common Securities held by
such Holder relative to the aggregate Liquidation Amount of all Common
Securities outstanding.

         9. Ranking.

         The Preferred Securities rank pari passu with the Common Securities and
payment thereon shall be made Pro Rata with the Common Securities, except that,
if an Event of Default under the Agreement occurs and is continuing, no payments
in respect of Distributions on, or payments upon liquidation, redemption or
otherwise with respect to, the Common Securities shall be made until the Holders
of the Preferred Securities shall be paid in full the Distributions, Liquidation
Distribution, Redemption Price and other payments to which they are entitled at
such time.

         10. Acceptance of Securities Guarantees and Indenture.

         Each Holder of Preferred Securities and Common Securities, by the
acceptance thereof, agrees to the provisions of the Preferred Securities
Guarantee, the Common Securities Guarantee and the Indenture, including the
subordination provisions therein.

         11. No Preemptive Rights.

         The Holders of the Preferred Securities and the Common Securities shall
have no preemptive or similar rights to subscribe for any additional securities.

                                      I-9
<PAGE>   76
         12. Miscellaneous.

         These terms constitute a part of the Agreement.

         The Sponsor will provide a copy of the Agreement, the Preferred
Securities Guarantee or the Common Securities Guarantee (as may be appropriate)
and the Indenture (including any supplemental indenture) to a Holder without
charge on written request to the Sponsor at its principal place of business.

                                      I-10
<PAGE>   77
                                   EXHIBIT A-1

                     FORM OF PREFERRED SECURITY CERTIFICATE

                           [FORM OF FACE OF SECURITY]

                  [IF THIS PREFERRED SECURITY IS A GLOBAL PREFERRED SECURITY,
INSERT: THIS PREFERRED SECURITY IS A GLOBAL PREFERRED SECURITY WITHIN THE
MEANING OF THE AGREEMENT HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME
OF THE DEPOSITORY TRUST COMPANY (THE "CLEARING AGENCY") OR A NOMINEE OF THE
CLEARING AGENCY. THIS PREFERRED SECURITY IS EXCHANGEABLE FOR PREFERRED
SECURITIES REGISTERED IN THE NAME OF A PERSON OTHER THAN THE CLEARING AGENCY OR
ITS NOMINEE ONLY IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE AGREEMENT AND NO
TRANSFER OF THIS PREFERRED SECURITY (OTHER THAN A TRANSFER OF THIS PREFERRED
SECURITY AS A WHOLE BY THE CLEARING AGENCY TO A NOMINEE OF THE CLEARING AGENCY
OR BY A NOMINEE OF THE CLEARING AGENCY TO THE CLEARING AGENCY OR ANOTHER NOMINEE
OF THE CLEARING AGENCY) MAY BE REGISTERED EXCEPT IN LIMITED CIRCUMSTANCES.

                  UNLESS THIS PREFERRED SECURITY IS PRESENTED BY AN AUTHORIZED
REPRESENTATIVE OF THE CLEARING AGENCY TO THE TRUST OR ITS AGENT FOR REGISTRATION
OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY PREFERRED SECURITY ISSUED IS
REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF THE CLEARING AGENCY AND ANY PAYMENT HEREON IS MADE
TO CEDE & CO., ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE
BY A PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN
INTEREST HEREIN.]

                  THE SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS.
NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED,
SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT
SUBJECT TO, REGISTRATION UNDER THE SECURITIES ACT AND ANY APPLICABLE STATE
SECURITIES LAWS.

                  THE HOLDER OF THE SECURITY BY ITS ACCEPTANCE HEREOF AGREES NOT
TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY PRIOR TO THE DATE (THE
"RESALE RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH HERCULES TRUST VI (THE
"TRUST") OR ANY AFFILIATED PERSON OF THE TRUST WAS THE OWNER OF THIS SECURITY
(OR ANY PREDECESSOR OF SUCH SECURITY) UNLESS SUCH OFFER, SALE OR OTHER

                                      A1-1
<PAGE>   78
TRANSFER IS (A) TO THE TRUST OR HERCULES INCORPORATED OR ANY OF ITS
SUBSIDIARIES, (B) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED
EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS THE SECURITIES ARE
ELIGIBLE FOR RESALE PURSUANT TO RULE 144A, TO A PERSON WHO IS OR WHO THE HOLDER
REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A
UNDER THE SECURITIES ACT THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT
OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS
BEING MADE IN RELIANCE ON RULE 144A, (D) TO AN "ACCREDITED INVESTOR" (AS DEFINED
IN RULE 501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT) THAT IS AN
INSTITUTIONAL INVESTOR, (E) PURSUANT TO OFFERS AND SALES TO NON-U.S. PERSONS
THAT OCCUR OUTSIDE THE UNITED STATES WITHIN THE MEANING OF REGULATION S UNDER
THE SECURITIES ACT OR (F) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE RIGHT OF THE
TRUST OR THE TRANSFER AGENT FOR THE SECURITIES PRIOR TO ANY SUCH OFFER, SALE OR
TRANSFER PURSUANT TO CLAUSES (D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN
OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH
OF THEM. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE THEN HOLDER OF THIS
SECURITY AFTER THE RESALE RESTRICTION TERMINATION DATE.

                                      A1-2
<PAGE>   79
Certificate Number                                          Number of Preferred
                                                            Securities

PS-001                                                      ___________

                                                            CUSIP NO. _________

                   Certificate Evidencing Preferred Securities

                                       of

                                HERCULES TRUST VI

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

                       Floating Rate Preferred Securities
               (liquidation amount $1,000 per Preferred Security)

                  HERCULES TRUST VI, a statutory business trust created under
the laws of the State of Delaware (the "Trust"), hereby certifies that
______________ (the "Holder") is the registered owner of 170,000 securities of
the Trust representing undivided beneficial interests in the assets of the Trust
designated as the Floating Rate Preferred Securities (liquidation amount $1,000
per Preferred Security) (the "Preferred Securities"). The Preferred Securities
are transferable on the books and records of the Trust, in person or by a duly
authorized attorney, upon surrender of this certificate duly endorsed and in
proper form for transfer.

                  The designation, rights, privileges, restrictions, preferences
and other terms and provisions of the Preferred Securities represented hereby
are issued and shall in all respects be subject to the provisions of the Amended
and Restated Trust Agreement of the Trust dated as of December 23, 1999, as the
same may be amended from time to time (the "Agreement"), including the
designation of the terms of the Preferred Securities as set forth in Annex I to
the Agreement. Capitalized terms used but not defined herein shall have the
respective meanings given them in the Agreement. The Sponsor will provide a copy
of the Agreement, the Preferred Securities Guarantee and the Indenture to a
Holder without charge upon written request to the Trust at its principal place
of business.

                  Upon receipt of this certificate, the Holder is bound by the
Agreement and is entitled to the benefits thereunder and to the benefits of the
Preferred Securities Guarantee to the extent provided therein.

                  By acceptance, the Holder agrees to treat, for United States
Federal income tax purposes, the Debentures as indebtedness and the Preferred
Securities as evidence of indirect beneficial ownership in the Debentures.

                                      A1-3
<PAGE>   80
                  IN WITNESS WHEREOF, the Trust has executed this certificate
this _______ day of ______________, 1999.

                                            HERCULES TRUST VI

                                            By: ________________________________

                                                Name:
                                                Title:    Administrative Trustee

         PROPERTY TRUSTEE'S CERTIFICATE OF AUTHENTICATION

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

Dated: ___________, 1999
                                            THE CHASE MANHATTAN BANK,
                                            as Property Trustee

                                            By: ________________________________
                                                Authorized Signatory

                                      A1-4
<PAGE>   81
                     [FORM OF REVERSE OF PREFERRED SECURITY]

         Distributions on the Preferred Securities will be payable at a rate per
annum, reset quarterly, equal to LIBOR (as defined in the Agreement) plus 245
basis points (2.45%) of the $1,000 liquidation amount per security (the
"Distribution Rate"). The Distribution Rate for any Distribution Period will at
no time be higher than the maximum rate then permitted by New York law, as the
same may be modified by United States law. Distributions in arrears for more
than one quarterly period will bear additional distributions thereon compounded
quarterly at the applicable periodic Distribution Rate (to the extent permitted
by applicable law). The term "Distributions", as used herein, includes any such
additional distributions unless otherwise stated. A Distribution is payable only
to the extent that payments are made in respect of the Debentures held by the
Property Trustee and to the extent the Property Trustee has funds legally
available therefor.

         Distributions on the Preferred Securities will be cumulative, will be
payable quarterly in arrears on March 29, 2000, June 29, 2000, September 29,
2000 and December 29, 2000 (each, a "Distribution Date"), will accumulate from
and including the most recent date to which Distributions have been paid or, if
no Distributions have been paid, from and including December 23, 1999, to but
excluding the related Distribution Date (a "Distribution Period").

         The amount of Distributions payable for any Distribution Period will be
computed on the basis of the actual number of days in such Distribution Period
and a year of 360 days. If a Distribution Date is not a Business Day, then such
Distribution Date will be postponed to the next succeeding Business Day.
However, if the next succeeding Business Day is in the next succeeding calendar
month, such Distribution Date will be the immediately preceding Business Day.

         Distributions on a Distribution Date will be payable to the Holders
thereof as they appear on the books and records of the Trust on the day
immediately preceding such Distribution Date. If the Preferred Securities are
ever issued in the form of Definitive Preferred Securities, the record date for
the payment of Distributions shall be the 15th day of the calendar month in
which the Distribution Date occurs, even if that day is not a Business Day. The
relevant record dates for the Common Securities shall be the same as the record
dates for the Preferred Securities. Distributions payable on any Securities that
are not punctually paid or duly provided for on any Distribution Date, as a
result of the Debenture Issuer having failed to make a payment under the
Debentures, will cease to be payable to the Holder on the relevant record date,
and such defaulted Distributions will instead be payable to the Person in whose
name such Preferred Securities are registered on the Special Record Date or
other specified date for the Debentures determined in accordance with the
Indenture.

         As long as no Event of Default has occurred and is continuing under the
Indenture, the Debenture Issuer has the right under the Indenture to defer
payments of interest on the Debentures by extending the interest payment period
at any time and from time to time (each period as to which interest payments
have been deferred is referred to herein as an "Extension Period"), provided
that an Extension Period must end on an Interest Payment Date for the

                                      A1-5
<PAGE>   82
Debentures and may not extend beyond December 29, 2000 (the "Stated Maturity
Date"). As a consequence of such deferral, Distributions on the Preferred
Securities will also be deferred during an Extension Period. Despite such
deferral, quarterly Distributions will continue to accumulate with additional
interest thereon (to the extent permitted by applicable law but not at a rate
greater than the rate at which interest is then accruing on the Debentures) at
the Distribution Rate then in effect, compounded quarterly during any Extension
Period. Prior to the termination of an Extension Period, the Debenture Issuer
may further defer payments of interest by further extending such Extension
Period; provided that an Extension Period, together with all such previous and
further extensions, may not extend beyond the Stated Maturity Date. At the end
of an Extension Period, all accumulated and unpaid Distributions (but only to
the extent payments are made in respect of the Debentures held by the Property
Trustee and to the extent the Property Trustee has funds legally available
therefor) will be payable to the Holders as they appear on the books and records
of the Trust on the record date immediately preceding the end of the Extension
Period. Upon the termination of any Extension Period (or any extension thereof)
and the payment of all amounts then due, the Debenture Issuer may commence a new
Extension Period, subject to the foregoing requirements.

                  Subject to other conditions set forth in the Agreement and the
Indenture, the Property Trustee may, at the direction of the Sponsor, dissolve
the Trust at any time and cause the Debentures to be distributed to the Holders
of the Preferred Securities in liquidation of the Trust or, simultaneously with
any redemption of the Debentures, cause a Like Amount of the Preferred
Securities to be redeemed by the Trust.

                  The Preferred Securities shall be redeemable as provided in
the Agreement.

                                      A1-6
<PAGE>   83
                                   ASSIGNMENT

                              _____________________

FOR VALUE RECEIVED, the undersigned assigns and transfers this Preferred
Security Certificate to:

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________
        (Insert assignee's social security or tax identification number)

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________
                    (Insert address and zip code of assignee)

and irrevocably appoints

________________________________________________________________________________

________________________________________________________________________________

_______________________________________________________________agent to transfer
this Preferred Security Certificate on the books of the Trust. The agent may
substitute another to act for him or her.

Date: _______________________

Signature: __________________
(Sign exactly as your name appears on the other side of this Preferred Security
Certificate)

Signature Guarantee**:   ___________________________________

______________________
**       Signature must be guaranteed by an "eligible guarantor institution"
         that is a bank, stockbroker, savings and loan association or credit
         union meeting the requirements of the Registrar, which requirements
         include membership or participation in the Securities Transfer Agents
         Medallion Program ("STAMP") or such other "signature guarantee program"
         as may be determined by the Registrar in addition to, or in
         substitution for, STAMP, all in accordance with the Securities and
         Exchange Act of 1934, as amended.

                                      A1-7
<PAGE>   84
[INCLUDE THE FOLLOWING IF THE PREFERRED SECURITY IS A RESTRICTED SECURITY]

In connection with any transfer of any of the Preferred Securities evidenced
hereby, the undersigned confirms that such Preferred Securities are being:

CHECK ONE BOX BELOW

         (1)      / /      exchanged for the undersigned's own account without
                  transfer; or

         (2)      / /      transferred to a "qualified institutional buyer" for
                  its own account or another "qualified institutional buyer" (as
                  defined in Rule 144A) in compliance with Rule 144A under the
                  Securities Act of 1933, as amended; or

         (3)      / /    transferred to an institutional "accredited investor"
                  within the meaning of subparagraph (a)(1), (2), (3) or (7) of
                  Rule 501 under the Securities Act of 1933 that is acquiring
                  the Preferred Securities for its own account, or for the
                  account of such an institutional "accredited investor," for
                  investment purposes and not with a view to, or offer or sale
                  in connection with, any distribution in violation of the
                  Securities Act of 1933, as amended; or

         (4)      / /    transferred pursuant to another available exemption
                  from the registration requirements of the Securities Act of
                  1933, as amended; or

         (5)      / /    transferred pursuant to an effective registration
                  statement.

         Unless one of the boxes is checked, the Transfer Agent will refuse to
register any of the Preferred Securities evidenced hereby in the name of any
Person other than the Holder hereof; provided, however, that if box (3) or (4)
is checked, the Transfer Agent may require, prior to registering any such
transfer of the Preferred Securities, such legal opinions, certifications and
other information as the Trust has reasonably requested to confirm that such
transfer is being made pursuant to an exemption from, or in a transaction not
subject to, the registration requirements of the Securities Act of 1933, as
amended; provided, further, that if box (2) is checked, by acceptance hereof,
the transferee shall be deemed to have certified that it is a "qualified
institutional buyer" acquiring the Preferred Securities for its own account or
for the account of another "qualified institutional buyer" over which it
exercises sole investment discretion and that it is aware that the Holder is
relying upon the exemption from registration afforded by Rule 144A in respect of
the Holder's transfer of Preferred Securities to it; provided, further, that
after the date that a registration statement has been filed and so long as such
Registration Statement continues to be effective, only then may the Transfer
Agent permit transfers for which (5) has been checked.

                                               _____________________________
                                                         Signature

                                      A1-8
<PAGE>   85
                                   EXHIBIT A-2

                       FORM OF COMMON SECURITY CERTIFICATE

                  THIS CERTIFICATE IS NOT TRANSFERABLE SUBJECT
                TO THE TERMS OF THE AGREEMENT (AS DEFINED HEREIN)

Certificate Number                                             Number of Common
                                                               Securities
CS-001                                                         ___________

                    Certificate Evidencing Common Securities

                                       of

                                HERCULES TRUST VI

                         Floating Rate Common Securities
                 (liquidation amount $1,000 per Common Security)

                  HERCULES TRUST VI, a statutory business trust created under
the laws of the State of Delaware (the "Trust"), hereby certifies that Hercules
Incorporated (the "Holder") is the registered owner of 5,258 securities of the
Trust representing undivided beneficial interests in the assets of the Trust
designated the Floating Rate Common Securities (liquidation amount $1,000 per
Common Security) (the "Common Securities"). The Common Securities are not
transferable. The designation, rights, privileges, restrictions, preferences and
other terms and provisions of the Common Securities represented hereby are
issued and shall in all respects be subject to the provisions of the Amended and
Restated Trust Agreement of the Trust dated as of December 23, 1999, as the same
may be amended from time to time (the "Agreement"), including the designation of
the terms of the Common Securities as set forth in Annex I to the Agreement.

                  Capitalized terms used but not defined herein shall have the
meaning given them in the Agreement. The Sponsor will provide a copy of the
Agreement, the Common Securities Guarantee and the Indenture to a Holder without
charge upon written request to the Trust at its principal place of business.

                  Upon receipt of this certificate, the Holder is bound by the
Agreement and is entitled to the benefits thereunder and to the benefits of the
Common Securities Guarantee to the extent provided therein.

                  By acceptance, the Holder agrees to treat, for United States
Federal income tax purposes, the Debentures as indebtedness and the Common
Securities as evidence of indirect beneficial ownership in the Debentures.

                                      A2-1
<PAGE>   86
                  IN WITNESS WHEREOF, the Trust has executed this certificate
this __________ day of _______________, 1999.

                                            HERCULES TRUST VI

                                            By: ________________________________
                                                Name:
                                                Title:    Administrative Trustee

                                      A2-2
<PAGE>   87
                          [FORM OF REVERSE OF SECURITY]

         Distributions on the Common Securities will be payable at a rate per
annum, reset quarterly, equal to LIBOR (as defined in the Agreement) plus 245
basis points (2.45%) of the $1,000 liquidation amount per security (the
"Distribution Rate"). The Distribution Rate for any Distribution period will at
no time be higher than the maximum rate then permitted by New York law, as the
same may be modified by United States law. Distributions in arrears for more
than one quarterly period will bear additional distributions thereon compounded
quarterly at the applicable periodic Distribution Rate (to the extent permitted
by applicable law). The term "Distributions", as used herein, includes any such
additional distributions unless otherwise stated. A Distribution is payable only
to the extent that payments are made in respect of the Debentures held by the
Property Trustee and to the extent the Property Trustee has funds legally
available therefor.

         Distributions on the Common Securities will be cumulative, will be
payable quarterly in arrears on March 29, 2000, June 29, 2000, September 29,
2000 and December 29, 2000 (each, a "Distribution Date"), will accumulate from
and including the most recent date to which Distributions have been paid or, if
no Distributions have been paid, from and including December 23, 1999, to but
excluding the related Distribution Date (a "Distribution Period").

         The amount of Distributions payable for any Distribution Period will be
computed on the basis of the actual number of days in such Distribution Period
and a year of 360 days. If a Distribution Date is not a Business Day, then such
Distribution Date will be postponed to the next succeeding Business Day.
However, if the next succeeding Business Day is in the next succeeding calendar
month, such Distribution Date will be the immediately preceding Business Day.

         Distributions on a Distribution Date will be payable to the Holders
thereof as they appear on the books and records of the Trust on the day
immediately preceding such Distribution Date. If the Preferred Securities are
ever issued in the form of Definitive Preferred Securities, the record date for
the payment of Distributions shall be the 15th day of the calendar month in
which the Distribution Date occurs, even if that day is not a Business Day. The
relevant record dates for the Common Securities shall be the same as the record
dates for the Preferred Securities. Distributions payable on any Securities that
are not punctually paid or duly provided for on any Distribution Date, as a
result of the Debenture Issuer having failed to make a payment under the
Debentures, will cease to be payable to the Holder on the relevant record date,
and such defaulted Distributions will instead be payable to the Person in whose
name such Preferred Securities are registered on the Special Record Date or
other specified date for the Debentures determined in accordance with the
Indenture.

         As long as no Event of Default has occurred and is continuing under the
Indenture, the Debenture Issuer has the right under the Indenture to defer
payments of interest on the Debentures by extending the interest payment period
at any time and from time to time (each

                                      A2-3
<PAGE>   88
period as to which interest payments have been deferred is referred to herein as
an "Extension Period"), provided that an Extension Period must end on an
Interest Payment Date for the Debentures and may not extend beyond December 29,
2000 (the "Stated Maturity Date"). As a consequence of such deferral,
Distributions on the Common Securities will also be deferred during an Extension
Period. Despite such deferral, quarterly Distributions will continue to
accumulate with additional interest thereon (to the extent permitted by
applicable law but not at a rate greater than the rate at which interest is then
accruing on the Debentures) at the Distribution Rate then in effect, compounded
quarterly during any Extension Period. Prior to the termination of an Extension
Period, the Debenture Issuer may further defer payments of interest by further
extending such Extension Period; provided that an Extension Period, together
with all such previous and further extensions, may not extend beyond the Stated
Maturity Date. At the end of an Extension Period, all accumulated and unpaid
Distributions (but only to the extent payments are made in respect of the
Debentures held by the Property Trustee and to the extent the Property Trustee
has funds legally available therefor) will be payable to the Holders as they
appear on the books and records of the Trust on the record date immediately
preceding the end of the Extension Period. Upon the termination of any Extension
Period (or any extension thereof) and the payment of all amounts then due, the
Debenture Issuer may commence a new Extension Period, subject to the foregoing
requirements.

                  Subject to other conditions set forth in the Agreement and the
Indenture, the Property Trustee may, at the direction of the Sponsor, dissolve
the Trust at any time and cause the Debentures to be distributed to the Holders
of the Preferred Securities in liquidation of the Trust or, simultaneously with
any redemption of the Debentures, cause a Like Amount of the Preferred
Securities to be redeemed by the Trust.

                  The Common Securities shall be redeemable as provided in the
Agreement.

                                      A2-4

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