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                                                                   EXHIBIT 10.43

                       CAREMARK RX, INC. TRUST AGREEMENT


                          DATED AS OF NOVEMBER 4, 1999


                                  BY AND AMONG


                               CAREMARK RX, INC.


                                      AND


                       LASALLE BANK NATIONAL ASSOCIATION,
AS TRUSTEE

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                       CAREMARK RX, INC. TRUST AGREEMENT


                  CAREMARK RX, INC. TRUST AGREEMENT (this "AGREEMENT") dated as
of November 4, 1999, by and among Caremark Rx, Inc. (formerly MedPartners,
Inc.), a Delaware corporation (the "COMPANY") and LaSalle Bank National
Association, a national banking association (the "TRUSTEE"), as Trustee
hereunder for the holders of the Secured Debt (as defined below).

                            PRELIMINARY STATEMENTS:

                  (1)      The Company has issued $450,000,000.00 of its 7%
Senior Notes due 2006 (the "SENIOR PUBLIC NOTES") pursuant to an Indenture
dated as of October 8, 1996 (the "INDENTURE") among the Company and The First
National Bank of Chicago, as Trustee, as supplemented to the date hereof. U.S.
Bank Trust National Association, as Trustee (the "PUBLIC TRUSTEE"), has
succeeded The First National Bank of Chicago as Trustee under the Indenture.

                  (2)      The Company has entered into a $1,000,000,000.00
Amended and Restated Credit Agreement dated as of June 9, 1998, as amended and
otherwise modified by Amendment and Waiver No. 1 to the Loan Documents dated as
of December 4, 1998, Amendment No. 2 to the Loan Documents dated as of January
13, 1999, Amendment No. 3 to the Loan Documents dated as of February 9, 1999,
Amendment and Waiver No. 4 to the Loan Documents dated as of March 18, 1999,
Amendment and Waiver No. 5 to the Loan Documents dated as of April 1, 1999,
Amendment No. 6 to the Loan Documents dated as of April 14, 1999, Amendment No.
7 to the Loan Documents dated as of June 29, 1999, Amendment No. 8 to the Loan
Documents dated as of July 9, 1999, Amendment No. 9 to the Loan Documents
("AMENDMENT NO. 9") dated as of August 16, 1999, Amendment No. 10 to the Loan
Documents dated as of August 30, 1999, Amendment No. 11 to the Loan Documents
dated as of August 30, 1999, and Amendment No. 12 to the Loan Documents dated
as of September 14, 1999, (as so amended and as hereafter amended, restated or
otherwise modified, the "CREDIT AGREEMENT"; and, together with the Indenture,
the "DEBT INSTRUMENTS"), with the financial institutions party thereto from
time to time as lenders, swing line banks and issuing banks (such lenders,
swing line banks and issuing banks, collectively, the "PRIVATE LENDERS"; or the
"HOLDERS OF THE BANK DEBT"), Credit Lyonnais New York Branch, The First
National Bank of Chicago and Morgan Guaranty Trust Company of New York, as
syndication agents, Banc of America Securities LLC (formerly known as
NationsBanc Montgomery Securities LLC), as arranger and Bank of America, N.A.
(formerly known as NationsBank, N.A.) as administrative agent (the
"ADMINISTRATIVE AGENT").

                  (3)      In order to fulfill its obligations pursuant to
Section 3 of Amendment No. 9 and in order to comply with the provisions of
Section 1009 of the Indenture, the Company has agreed to secure, equally and
ratably subject to the terms and conditions of this Agreement and the Pledge
Agreement dated as of the date hereof, among the Company and the Trustee (the
"PLEDGE AGREEMENT"; and, together with all documents and filings related
thereto, the "SECURITY DOCUMENTS"), the payment of all of its obligations owing
under the Credit Agreement and the documents delivered in connection therewith
(the "BANK DEBT") and the payment of all of its obligations owing under the
Senior Public Notes (the Bank Debt and the Senior Public Notes being,
collectively, the "SECURED DEBT").


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                             DECLARATION OF TRUST:

                  NOW THEREFORE, in order to secure the Secured Debt and in
consideration of the premises and the mutual agreements set forth herein, the
Trustee hereby declares that it holds as trustee in trust under this Agreement
all of its right, title and interest in, to and under all the following (and
the Company does hereby consent thereto):

                  (A)      the Security Documents and the collateral granted to
         the Trustee thereunder (the "PLEDGED COLLATERAL"); and

                  (B)      each agreement entered into and delivered pursuant
         to Section 4.7 or Section 7.1(b) and the collateral granted to the
         Trustee thereunder (the "SUPPLEMENTAL COLLATERAL"; and, together with
         the Pledged Collateral, the "COLLATERAL").

                  TO HAVE AND TO HOLD, the foregoing Pledged Collateral and the
entire Collateral (the right, title and interest of the Trustee in the Security
Documents and the Collateral being hereinafter referred to as the "TRUST
ESTATE") unto the Trustee and its successors in trust under this Agreement and
its assigns and the assigns of its successors in trust forever;

                  IN TRUST NEVERTHELESS, under and subject to the terms and
conditions herein set forth and for the benefit of the holders of the Secured
Debt and for the enforcement of the payment of all of the Secured Debt, and for
the performance of and compliance with the covenants and conditions of this
Agreement, the Debt Instruments and the Security Documents.

                  PROVIDED, HOWEVER, that these presents are upon the condition
that if the Company, its successors or assigns, shall satisfy all of the
conditions set forth in Section 6, then this Agreement, and the estates and
rights assigned in the Security Documents, shall cease, terminate and be void;
otherwise they shall remain and be in full force and effect.

                  IT IS HEREBY FURTHER COVENANTED AND DECLARED, that the Trust
Estate is to be held and applied by the Trustee, subject to the further
covenants, conditions and trusts hereinafter set forth.

                                   SECTION 1

                         DEFINITIONS AND OTHER MATTERS

                  (a)      The words "hereof", "herein" and "hereunder" and
words of similar import when used in this Agreement shall refer to this
Agreement as a whole and not to any particular provision of this Agreement and
section references are to this Agreement unless otherwise specified.

                  (b)      In each case herein where "Holders" are entitled to
vote on any matter or to instruct the Trustee, the Public Trustee shall so vote
or instruct the Trustee on behalf of the holders of the Senior Public Notes. In
each case herein where any payment or distribution is to be made or notice is
to be given to "Holders," such payments, distributions and notices in respect
of the Senior Public Notes shall be made to the Public Trustee for the benefit
of the holders thereof pursuant to the terms of the Indenture.


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                  (c)      As used in this Agreement, the following terms shall
have the following meanings (such meanings to be equally applicable to both the
singular and the plural forms of the terms defined:

                  "ACTIONABLE DEFAULT" means (i) the acceleration pursuant to
         Section 6.01 of the Credit Agreement of the maturity of the Bank Debt
         or (ii) the non-payment at maturity of the Senior Public Notes or the
         declaration prior to their stated maturity that all of the Senior
         Public Notes are due and payable pursuant to Section 502 of the
         Indenture; provided that an Actionable Default shall be deemed to be
         continuing unless the Notice of Actionable Default delivered with
         respect thereto shall have been withdrawn in a writing delivered to
         the Trustee by or on behalf of the Holder or Holders from or on behalf
         of which such Notice of Actionable Default was delivered, prior to the
         first date on which the Trustee commences the exercise of any remedy
         with respect to the Collateral following the receipt of such Notice of
         Actionable Default.

                  "BANKRUPTCY PROCEEDING" means that the Company or any of its
         subsidiaries shall generally not pay its debts as such debts become
         due, or shall admit in writing its inability to pay its debts
         generally, or shall make a general assignment for the benefit of
         creditors; or any proceeding shall be instituted by or against the
         Company or any of its subsidiaries seeking to adjudicate it a bankrupt
         or insolvent, or seeking liquidation, winding up, reorganization,
         arrangement, adjustment, protection, relief, or composition of it or
         its debts under any law relating to bankruptcy, insolvency or
         reorganization or relief of debtors, or seeking the entry of an order
         for relief or the appointment of a receiver, trustee, administrator or
         other similar official for it or for any substantial part of its
         property and assets and, in the case of any such proceeding instituted
         against it (but not instituted by it) that is being diligently
         contested by it in good faith, either such proceeding shall remain
         undismissed or unstayed for a period of at least 45 consecutive days
         or any of the actions sought in such proceeding (including, without
         limitation, the entry of an order for relief against, or the
         appointment of a receiver, trustee, custodian or other similar
         official for, it or any substantial part of its property and assets)
         shall occur; or any event or action analogous to or having a
         substantially similar effect to any of the events or actions set forth
         above in this definition (other than a solvent reorganization) shall
         occur under the law of any jurisdiction applicable to the Company or
         any of its subsidiaries; or the Company or any of its Subsidiaries
         shall take any corporate, partnership, limited liability company or
         other similar action to authorize any of the actions set forth above
         in this definition.

                  "DISTRIBUTION DATES" means the dates fixed by the Trustee
         (the first of which shall occur within 90 days after receipt of a
         Notice of Actionable Default that has not theretofore been withdrawn
         and the balance of which shall be monthly thereafter) for the
         distribution of all moneys held by the Trustee in the Trust Account.

                  "HOLDERS" means the holders of the Senior Public Notes and
         the holders of the Bank Debt.

                  "MAJORITY HOLDERS" means, as of any date, Holders holding
         more than 50% of (i) the aggregate unpaid principal amount of the
         Senior Public Notes then outstanding under the Indenture plus (ii) the
         aggregate unpaid principal amount of the Bank Debt under the Credit
         Agreement plus the aggregate obligations available under outstanding
         letters of credit thereunder.

                  "REQUIRED LENDERS" has the meaning set forth in Section 1.01
         of the Credit Agreement.


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                  "RESPONSIBLE OFFICER" means the chief executive officer, the
         president, the chief financial officer, the principal accounting
         officer or the treasurer (or the equivalent of any of the foregoing)
         of the Company or any of its subsidiaries or any other officer,
         partner or member (or person performing similar functions) of the
         Company or any of its subsidiaries responsible for overseeing the
         administration of, or reviewing compliance with, all or any portion of
         this Agreement or any of the Security Documents.

                  "TRUSTEE'S FEES" means all fees, costs and expenses of the
         Trustee of the type described in (i) Sections 4.3, 4.4, 4.5 and 4.6 of
         this Agreement or (ii) Section 15 of the Pledge Agreement.

                                   SECTION 2

                          ACTIONABLE DEFAULT; REMEDIES

                  2.1      Notice of Default; Written Instructions. (a) Upon
receipt of a notice of Actionable Default (a "NOTICE OF ACTIONABLE DEFAULT"),
the Trustee shall, within five days thereafter, notify the Public Trustee and
the Administrative Agent that an Actionable Default exists.

                  (b)      Upon receipt of any written directions pursuant to
Section 2.6(a), the Trustee shall, within five days thereafter, send a copy
thereof to the Administrative Agent and the Public Trustee.

                  2.2      Remedies. (a) If and only if the Trustee shall have
received a Notice of Actionable Default and such Notice of Actionable Default
shall not have been withdrawn in accordance with the provisions hereof, the
Trustee shall exercise the rights and remedies provided in this Agreement and
in the Security Documents.

                  SECTION 1  The Company hereby waives presentment, demand,
protest or any notice (to the extent permitted by applicable law) of any kind
in connection with this Agreement, any Collateral or any Security Document.

                  SECTION 2  The Company hereby irrevocably constitutes and
appoints the Trustee and any officer or agent thereof, with full power of
substitution, as its true and lawful attorney-in-fact with full power and
authority in the name of the Company or in its own name, from time to time in
the Trustee's discretion, upon the occurrence and during the continuance of an
Actionable Default, for the purpose of carrying out the terms of this Agreement
and the Security Documents, to take any and all appropriate action and to
execute any and all documents and instruments that may be necessary or
desirable to accomplish the purposes hereof and thereof and, without limiting
the generality of the foregoing, hereby gives the Trustee the power and right
on behalf of the Company, without notice to or assent by the Company, to do the
following:

                           (i)      to ask for, demand, sue for, collect,
         receive, recover, compromise and give acquittance and receipts for any
         and all moneys due or to become due upon or by virtue hereof and
         thereof,

                           (ii)     to receive, take, endorse, assign and
         deliver any and all checks, notes, drafts, acceptances, documents and
         other negotiable and non-negotiable instruments and chattel paper
         taken or received by the Trustee in connection herewith and therewith,


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                           (iii)    to commence, file, institute, prosecute,
         defend, settle, compromise or adjust any claim, suit, action or
         proceeding with respect hereto and thereto or in connection herewith
         and therewith,

                           (iv)     to sell, transfer, assign or otherwise deal
         in or with the Collateral or any part thereof as fully and effectually
         as if the Trustee were the absolute owner thereof, and

                           (v)      to do, at its option and at the expense and
         for the account of the Company, at any time or from time to time, all
         acts and things that the Trustee deems necessary to protect or
         preserve the Collateral or the Trust Estate and to realize upon the
         Collateral.

                  2.3      Right to Initiate Judicial Proceedings, etc. If and
only if the Trustee shall have received a Notice of Actionable Default and such
Notice of Actionable Default shall not have been withdrawn in accordance with
the provisions hereof, (i) the Trustee shall have the right and power to
institute and maintain such suits and proceedings as it may deem appropriate to
protect and enforce the rights vested in it by this Agreement and each Security
Document and (ii) the Trustee may, either after entry or without entry, proceed
by suit or suits at law or in equity to enforce such rights and to foreclose
upon the Collateral and to sell all or, from time to time, any of the Trust
Estate under the judgment or decree of a court of competent jurisdiction.

                  2.4      Appointment of a Receiver. If a receiver of the
Trust Estate shall be appointed in judicial proceedings, the Trustee may be
appointed as such receiver. Notwithstanding the appointment of a receiver, the
Trustee shall be entitled to retain possession and control of all cash held by
or deposited with it or its agents pursuant to any provision of this Agreement
or any Security Document.

                  2.5      Exercise of Powers. All of the powers, remedies and
rights of the Trustee as set forth in this Agreement may be exercised by the
Trustee in respect of any Security Document as though set forth at length
therein and all the powers, remedies and rights of the Trustee and the Holders
as set forth in any Security Document may be exercised from time to time as
herein and therein provided.

                  2.6      Control by Holders. (a) Subject to Section 2.6(b),
if an Actionable Default shall have occurred and be continuing and the Trustee
shall have received a Notice of Actionable Default with respect thereto, the
Majority Holders shall have the right, by an instrument in writing executed and
delivered to the Trustee, to direct the time, method and place of conducting
any proceeding for any right or remedy available to the Trustee, or of
exercising any trust or power conferred on the Trustee, or for the appointment
of a receiver, or for the taking of any action authorized by Section 2.

                  (b)      The Trustee shall not follow any written directions
received pursuant to Section 2.6(a) to the extent such written directions are
known by the Trustee to be in conflict with any provisions of law or if the
Trustee shall have received from independent counsel an unqualified opinion to
the effect that following such written directions would result in a breach of a
provision or covenant contained in the Indenture providing for the securing of
the indebtedness outstanding thereunder equally and ratably with other
indebtedness or obligations of the Company or any of its subsidiaries.

                  (c)      Nothing in this Section 2.6 shall impair the right
of the Trustee in its discretion to take or omit to take any action deemed
proper by the Trustee and which action or omission is not inconsistent with the
direction of the Holders entitled to direct the Trustee pursuant to this
Section 2.6; provided, however, that the Trustee shall not be under any
obligation to take any action that is discretionary with the Trustee under the
provisions hereof or under any Security Document.


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                  2.7      Remedies Not Exclusive. (a) No remedy conferred upon
or reserved to the Trustee herein or in any Security Document is intended to be
exclusive of any other remedy or remedies, but every such remedy shall be
cumulative and shall be in addition to every other remedy conferred herein or
in any Security Document or now or hereafter existing at law or in equity or by
statute.

                  (b)      No delay or omission of the Trustee to exercise any
right, remedy or power accruing upon any Actionable Default shall impair any
such right, remedy or power or shall be construed to be a waiver of any such
Actionable Default or an acquiescence therein; and every right, power and
remedy given by this Agreement or any Security Document to the Trustee may be
exercised from time to time and as often as may be deemed expedient by the
Trustee.

                  (c)      In case the Trustee shall have proceeded to enforce
any right, remedy or power under this Agreement or any Security Document and
the proceeding for the enforcement thereof shall have been discontinued or
abandoned for any reason or shall have been determined adversely to the
Trustee, then and in every such case the Company, the Trustee and the Holders
shall, subject to any determination in such proceeding, severally and
respectively be restored to their former positions and rights hereunder and
under such Security Document with respect to the Trust Estate and in all other
respects, and thereafter all rights, remedies and powers of the Trustee shall
continue as though no such proceeding had been taken.

                  (d)      All rights of action and rights to assert claims
upon or under this Agreement and the Security Documents may be enforced by the
Trustee without the possession of any Debt Instrument or the production thereof
in any trial or other proceeding relative thereto, and any such suit or
proceeding instituted by the Trustee shall be brought in its name as Trustee
and any recovery of judgment shall be held as part of the Trust Estate.

                  2.8      Waiver of Certain Rights. The Company, to the extent
it may lawfully do so, on behalf of itself and all who may claim through or
under it, including, without limitation, any and all subsequent creditors,
vendees, assignees and lienors, expressly waives and releases any, every and
all rights to demand or to have any marshaling of the Trust Estate upon any
sale, whether made under any power of sale herein granted or pursuant to
judicial proceedings or upon any foreclosure or any enforcement of this
Agreement and consents and agrees that all the Trust Estate may at any such
sale be offered and sold as an entirety.

                  2.9      Limitation on Trustee's Duties in Respect of
Collateral. Beyond its duties set forth in this Agreement as to the custody
thereof and the accounting to the Company and the Holders for moneys received
by it hereunder, the Trustee shall not have any duty to the Company and the
Holders as to any Collateral in its possession or control or in the possession
or control of any agent or nominee of it or any income thereon or as to the
preservation of rights against prior parties or any other rights pertaining
thereto. To the extent, however, that the Trustee or any agent or nominee
thereof maintains possession or control of any of the Collateral, the Trustee
shall, and shall instruct such agent or nominee to, grant the Company access to
such Security that the Company requires for the normal conduct of its business,
consistent with its current practice so long as the Trustee shall not have
received a Notice of Actionable Default.

                  2.10     Limitation by Law. All rights, remedies and powers
provided by this Section 2 may be exercised only to the extent that the
exercise thereof does not violate any applicable provision of law in the
premises, and all the provisions of this Section 2 are intended to be subject
to all applicable


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mandatory provisions of law that may be controlling in the premises and to be
limited to the extent necessary so that they will not render this Agreement
invalid, unenforceable in whole or in part or not entitled to be recorded,
registered, or filed under the provisions of any applicable law.

                  2.11     Absolute Rights of Holders. Notwithstanding any
other provision of this Agreement or any provision of any Security Document,
the right of each Holder, which is absolute and unconditional, to receive
payments of the Secured Debt held by such Holder on or after the due date
thereof as therein expressed, to seek adequate protection in respect of its
interest in this Agreement and the Collateral, to institute suit for the
enforcement of such payment on or after such due date, or to assert its
position and views as a secured creditor in a Bankruptcy Proceeding, or the
obligation of the Company, which is also absolute and unconditional, to pay the
Secured Debt to the Holders at the time and place expressed therein shall not
be impaired or affected without the consent of such Holder.

                  2.12     Equal and Ratable Security. This Agreement and the
Security Documents are intended to secure the unpaid principal of and accrued
interest and premium, if any, on the Senior Public Notes equally and ratably
with all indebtedness and other obligations of the Company under the Credit
Agreement, this Agreement and the Security Documents to the extent required by
the Indenture, and shall be construed and enforced to give effect to such
intention.

                                   SECTION 3

                     TRUST ACCOUNT, APPLICATION OF MONEYS.

                  3.1      The Trust Account. On the date hereof there shall be
established and, at all times thereafter until the trusts created by this
Agreement shall have terminated, there shall be maintained, with the Trustee an
account that shall be entitled the "Caremark Rx, Inc. Trust Account" (the
"TRUST ACCOUNT"). The Trust Account shall be established and maintained by the
Trustee at the office of its corporate trust services division. All moneys that
are received by the Trustee after the occurrence of an Actionable Default in
respect of the Collateral shall be deposited in the Trust Account and
thereafter shall be held and applied by the Trustee in accordance with the
terms of this Agreement.

                  3.2      Control of Trust Account. All right, title and
interest in and to the Trust Account shall vest in the Trustee, and funds on
deposit in the Trust Account shall constitute part of the Trust Estate. The
Trust Account shall be subject to the exclusive dominion and control of the
Trustee.

                  3.3      Investment of Funds Deposited in Trust Account. The
Trustee pursuant to written direction shall invest and reinvest moneys on
deposit in the Trust Account at any time in:

                           (i)      marketable obligations of the United States
         having a maturity of not more than one year from the date of
         acquisition;

                           (ii)     marketable obligations directly and fully
         guaranteed by the United States having a maturity of not more than one
         year from the date of acquisition;

                           (iii)    bankers' acceptances and certificates of
         deposit and other interest-bearing obligations issued by the Trustee
         or any bank organized under the laws of the United States or any state
         thereof with capital, surplus and undivided profits aggregating at
         least


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         $500,000,000 in each case having a maturity of not more than one year
         from the date of acquisition;

                           (iv)     repurchase obligations with a term of not
         more than thirty days for underlying securities of the types described
         in clauses (i), (ii) and (iii) entered into with either (A) the
         Trustee or any bank of the type described in clause (iii) above or (B)
         any nationally recognized investment banking firm;

                           (v)      commercial paper (except for commercial
         paper issued by the Company or its Affiliates) rated A-1 or the
         equivalent thereof by Standard & Poor's Ratings Services, a division
         of the McGraw-Hill Companies, Inc., or P-1 or the equivalent thereof
         by Moody's Investors Service, Inc.; and

                           (vi)     money market funds investing in obligations
         described in clauses (i), (ii) and (iv);

provided, however, that the maximum amount of the funds held in the Trust
Account that may be invested in obligations of the types described in clauses
(iii), (iv) and (v) above of any one issuer shall not exceed the lesser of 5%
of such funds or $50,000,000. All such investments and the interest and income
received thereon and therefrom and the net proceeds realized on the sale
thereof shall be held in the Trust Account as part of the Trust Estate.

                  3.4      Application of Moneys. (a) Subject to Sections 1(b)
and 3.5, all moneys held by the Trustee in the Trust Account shall, to the
extent available for distribution, be distributed (or deposited in a separate
account for the benefit of the Public Trustee pursuant to Section 3.5) by the
Trustee as follows:

                           FIRST: To the Trustee in an amount equal to the
         Trustee's Fees that are unpaid as of the relevant Distribution Date
         and to any Holder that has theretofore advanced or paid any such
         Trustee's Fees in an amount equal to the amount thereof so advanced or
         paid by such Holder prior to such Distribution Date;

                           SECOND: To the Holders in an amount equal to the
         unpaid principal of and unpaid interest on the Secured Debt whether or
         not then due and payable, and, in case such moneys shall be
         insufficient to pay in full such amount, then to the payment thereof
         ratably (without priority of any one over any other) to each Holder in
         the same proportion that the aggregate unpaid principal amount of and
         unpaid interest on the Secured Debt held by such Holder bears to the
         aggregate unpaid principal amount of and unpaid interest on the
         Secured Debt held by all Holders on the relevant Distribution Date;

                           THIRD: To the Holders in an amount equal to all
         other unpaid Secured Debt whether or not due and payable, and, in case
         such moneys shall be insufficient to pay in full such amount, then to
         the payment thereof ratably (without priority of any one over any
         other) to each Holder in the same proportion that such other unpaid
         Secured Debt of such Holder bears to all such other unpaid Secured
         Debt of all Holders on the relevant Distribution Date; and

                           FOURTH: Any surplus then remaining shall be paid to
         the Company, its successors or assigns, or to whomsoever may be
         lawfully entitled to receive the same, or as a court of competent
         jurisdiction may direct.


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                  (b)      The term "unpaid" as used in this Section 3.4 shall
mean all amounts of Trustee's Fees and the Secured Debt outstanding as of a
Distribution Date as to which prior distributions (whether actually distributed
or set aside pursuant to Section 3.5) have not been made, or if made, have
subsequently been recovered from the recipient thereof.

                  3.5      Application of Moneys Distributable to Holders of
Senior Public Notes. If at any time any moneys collected or received by the
Trustee pursuant to this Agreement or any Security Document are distributable
pursuant to Section 3.4(a) to the Public Trustee, and if the Public Trustee
shall notify the Trustee that no provision is made under the Indenture (i) for
the application by the Public Trustee of such amounts so distributable (whether
by virtue of the Secured Debt issued under the Indenture not having become due
and payable or otherwise) or (ii) for the receipt and the holding by the Public
Trustee of such amounts pending the application thereof, then the Trustee shall
invest such amounts in obligations of the kinds referred to in Section 3.3(i),
3.3(ii) or 3.3(vi) having maturities of 90 days or less, and shall hold all
such amounts so distributable, and all such investments and the proceeds
thereof, in trust solely for the Public Trustee and for no other purpose until
such time as the Public Trustee shall request the delivery thereof by the
Trustee to the Public Trustee for application by it pursuant to the Indenture.

                                   SECTION 4

                          AGREEMENTS WITH THE TRUSTEE

                  4.1      Delivery of Debt Instruments. Within 10 days after
the date hereof, the Company will deliver to the Trustee a true and complete
copy of each of the Debt Instruments as in effect on the date hereof. The
Company agrees that, promptly upon the execution thereof, the Company will
deliver to the Trustee a true and complete copy of any and all amendments,
modifications or supplements to any Debt Instrument entered into subsequent to
the date hereof.

                  4.2      Information as to Holders. The Company agrees that
it shall deliver to the Trustee from time to time upon request of the Trustee,
a list setting forth, by each Debt Instrument, (i) the aggregate principal
amount outstanding thereunder, (ii) the interest rates then in effect
thereunder and (iii) to the extent known to the Company, the names of the
Holders of the Secured Debt outstanding thereunder and the unpaid principal
amount thereof owing to each Private Lender and the Public Trustee. The Company
will furnish to the Trustee within 30 days after the date hereof a list setting
forth the name and address of each party to whom notices must be sent under the
Debt Instruments.

                  4.3      Compensation and Expenses. The Company agrees to pay
to the Trustee, from time to time upon demand, (i) reasonable compensation
(which shall not be limited by any provision of law in regard to compensation
of a trustee of an express trust) for their services hereunder and under the
Security Documents and for administering the Trust Estate and (ii) all of the
fees, costs and expenses of the Trustee (including, without limitation, the
reasonable fees and disbursements of their counsel and such special counsel as
the Trustee elect to retain) (A) arising in connection with the preparation,
execution, delivery, modification and termination of this Agreement and each
Security Document or the enforcement of any of the provisions hereof or thereof
or (B) incurred or required to be advanced in connection with the
administration of the Trust Estate, the sale or other disposition of Collateral
pursuant to any Security Document and the preservation, protection or defense
of the Trustee's rights under this Agreement and in and to the Collateral and
the Trust Estate.


<PAGE>   11

                  4.4      Stamp and Other Similar Taxes. The Company agrees to
indemnify and hold harmless the Trustee and each Holder from any present or
future claim for liability for any stamp or other similar tax and any penalties
or interest with respect thereto that may be assessed, levied or collected by
any jurisdiction in connection with this Agreement, any Security Document, the
Trust Estate or any Collateral. The obligations of the Company under this
Section 4.4 shall survive the termination of the other provisions of this
Agreement.

                  4.5      Filing Fees, Excise Taxes, etc. The Company agrees
to pay or to reimburse the Trustee for any and all amounts in respect of all
search, filing, recording and registration fees, taxes, excise taxes and other
similar imposts that may be payable or determined to be payable in respect of
the execution, delivery, performance and enforcement of this Agreement and each
Security Document. The obligations of the Company under this Section 4.5 shall
survive the termination of the other provisions of this Agreement.

                  4.6      Indemnification. The Company agrees to pay,
indemnify, and hold the Trustee and each of its agents harmless from and
against any and all liabilities, obligations, losses, damages, penalties,
actions, judgments, suits, costs, expenses or disbursements of any kind or
nature whatsoever with respect to the execution, delivery, enforcement,
performance and administration of this Agreement and the Security Documents
(including, but not limited to, actions by the Trustee to enforce its rights
with respect to the Collateral), unless arising from the gross negligence or
willful misconduct (in either case, as determined by a final judgment of a
court of competent jurisdiction) of the Trustee or such of the agents as are
seeking indemnification. The foregoing indemnities in this Section 4.6 shall
survive the resignation or removal of the Trustee or the termination of this
Agreement.

                  4.7      Further Assurances; Notation on Financial
Statements. At any time and from time to time, upon the written request of the
Trustee, and, at the sole expense of the Company, the Company will promptly
execute and deliver any and all such further instruments and documents and take
such further action as the Trustee reasonably deems necessary or desirable in
obtaining the full benefits of this Agreement and the Security Documents and of
the rights and powers herein and therein granted. To the extent required by
law, the Company shall, in all of its financial statements, indicate by
footnote or otherwise that the Secured Debt is secured pursuant to this
Agreement and the Security Documents.

                                   SECTION 5

                                  THE TRUSTEE

                  5.1      Acceptance of Trust. The Trustee, for itself and its
successors, hereby accepts the trusts created by this Agreement upon the terms
and conditions hereof, including those contained in this Section 5.

                  5.2      Exculpatory Provisions. (a) The Trustee shall not be
responsible in any manner whatsoever for the correctness of any recitals,
statements, representations or warranties' contained herein or in any Security
Document, all of which are made solely by the Company. The Trustee makes no
representations as to the value or condition of the Trust Estate or any part
thereof, or as to the title of the Company thereto or as to the security
afforded by any Security Document or this Agreement, or as to the validity,
execution (except its own execution), enforceability, legality or sufficiency
of this Agreement, any Security Document or the Secured Debt secured hereby and
thereby, and the Trustee shall incur no liability or responsibility in respect
of any such matters. The Trustee shall not be responsible for


<PAGE>   12

insuring the Trust Estate or for the payment of taxes, charges, assessments or
liens upon the Trust Estate or otherwise as to the maintenance of the Trust
Estate, except that in the event the Trustee enters into possession of a part
or all of the Trust Estate, the Trustee shall preserve the part in its
possession.

                  (b)      The Trustee shall not be required to ascertain or
inquire as to the performance by the Company of any of the covenants or
agreements contained herein, in any Security Document or in any Debt
Instrument. Whenever it is necessary, or in the opinion of the Trustee
advisable, for the Trustee to ascertain the amount of Secured Debt then held by
a Holder, the Trustee may rely on a certificate of such Holder or its
representative as to such amount, and if any such Holder or representative
shall not give such information to the Trustee, such Holder shall not be
entitled to receive distributions hereunder (in which case such distributions
shall be held in trust for such Holder) until it has given such information to
the Trustee.

                  (c)      The Trustee shall not be personally liable for any
action taken or omitted to be taken by them in accordance with this Agreement
or any Security Document except for its own gross negligence or willful
misconduct.

                  5.3      Delegation of Duties. The Trustee may execute any of
the trusts or powers hereof and perform any duty hereunder either directly or
by or through agents or attorneys-in-fact, which may include officers and
employees of the Company. The Trustee shall be entitled to advice of counsel
concerning all matters pertaining to such trusts, powers and, duties. The
Trustee shall not be responsible for the negligence or misconduct of any agents
or attorneys-in-fact selected by it without gross negligence or willful
misconduct.

                  5.4      Reliance by Trustee. (a) Whenever in the
administration of the trusts of this Agreement the Trustee shall deem it
necessary or desirable that a matter be proved or established in connection
with the taking, suffering or omitting any action hereunder by the Trustee,
such matter (unless other evidence in respect thereof be herein specifically
prescribed) may be deemed to be conclusively provided or established by a
certificate of a Responsible Officer of the Company delivered to the Trustee,
and such certificate shall be full warranty to the Trustee for any action
taken, suffered or omitted in reliance thereon, subject, however, to the
provisions of Section 5.5.

                  (b)      The Trustee may consult with counsel, and any
opinion of such counsel who are not employees of the Trustee shall be full and
complete authorization and protection in respect of any action taken or
suffered by it hereunder in accordance therewith. The Trustee shall have the
right at any time to seek, instructions concerning the administration of the
Trust Estate from any court of competent jurisdiction.

                  (c)      The Trustee may rely, and shall be fully protected
in acting, upon any resolution, statement, certificate, instrument, opinion,
report, notice, request, consent, order, bond or other paper or document that
it has no reason to believe to be other than genuine and to have been signed or
presented by the proper party or parties or, in the case of cables, telecopies
and telexes, to have been sent by the proper party or parties. In the absence
of its gross negligence or willful misconduct, the 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 Trustee
and conforming to the requirements of this Agreement or any Security Document.

                  (d)      The Trustee shall not be under any obligation to
exercise any of the rights or powers vested in the Trustee by this Agreement at
the request or direction of the Majority Holders


<PAGE>   13

pursuant to this Agreement or any Security Document unless the Trustee shall
have been provided adequate security and indemnity against the costs, expenses
and liabilities that may be incurred by it in compliance with such request or
direction, including such reasonable advances as may be requested by the
Trustee.

                  5.5      Limitations on Duties of Trustee. (a) Prior to the
occurrence of an Actionable Default, the Trustee shall be obliged to perform
such duties and only such duties as are specifically set forth in this
Agreement or in any Security Document, and no implied covenants or obligations
shall be read into this Agreement or any Security Document against the Trustee.
The Trustee shall, during the existence of any Actionable Default, exercise the
rights and powers vested in it by this Agreement or by any Security Document,
and the Trustee shall not be liable with respect to any action taken or omitted
by it in accordance with the direction of the Holders pursuant to Section 2.6.

                  (b)      Except as herein otherwise expressly provided, the
Trustee shall not be under any obligation to take any action that is
discretionary with the Trustee under the provisions hereof or under any
Security Document except upon the written request of the Holders pursuant to
Section 2.6. The Trustee shall make available for inspection and copying by the
Administrative Agent and the Public Trustee each certificate or other paper
furnished to the Trustee by the Company under or in respect of this Agreement,
any Security Document or any of the Trust Estate.

                  5.6      Moneys to be Held in Trust. All moneys received by
the Trustee under or pursuant to any provision of this Agreement or any
Security Document shall be held in trust for the purposes for which they were
paid or are held.

                  5.7      Resignation and Removal of the Trustee. (a) The
Trustee may at any time, by giving 30 days' prior written notice to the Company
and the Holders, resign and be discharged of the responsibilities hereby
created, such resignation to become effective upon the earlier of (i) 30 days
from the date of such notice and (ii) the appointment of a successor trustee or
trustees by the Company, the acceptance of such appointment by such successor
trustee or trustees, and the approval of such successor trustee or trustees by
the Majority Holders. The Trustee may be removed at any time and a successor
trustee or trustees appointed by the affirmative vote of the Majority Holders;
provided that the Trustee shall be entitled to its fees and expenses to the
date of removal. If no successor trustee or trustees shall be appointed and
approved within 30 days, from the date of the giving of the aforesaid notice of
resignation or within 30 days from the date of such removal, the Trustee
(notwithstanding the termination of all of its duties and obligations hereunder
by reason of such resignation) shall, or any Holder may, apply to any court of
competent jurisdiction to appoint a successor trustee or trustees (which may be
an individual or individuals) to act until such time, if any, as a successor
trustee or trustees shall have been appointed as above provided. Any successor
trustee or trustees so appointed by such court shall immediately and without
further act be superseded by any successor trustee or trustees approved by the
Majority Holders as above provided.

                  (b)      If at any time the Trustee shall resign or be
removed or otherwise become incapable of acting, or if at any time, a vacancy
shall occur in the office of the Trustee for any other cause, a successor
trustee or trustees may be appointed by the Majority Holders, and the powers,
duties, authority and title of the predecessor trustee or trustees terminated
and canceled without procuring the resignation of such predecessor trustee or
trustees, and without any other formality (except as may be required by
applicable law) than appointment and designation of a successor trustee or
trustees in writing, duly acknowledged, delivered to the predecessor trustee or
trustees and the Company, and filed for record in each public office, if any,
in which this Agreement is required to be filed.


<PAGE>   14

                  (c)      The appointment and designation referred to in
Section 5.7(b) shall, after any required filing, be full evidence of the right
and authority to make the same and of all the facts therein recited, and this
Agreement shall vest in such successor trustee or trustees, without any further
act, deed or conveyance, all of the estate and title of its predecessor, and
upon such filing, for record the successor trustee or trustees shall become
fully vested with all the estates, properties, rights, powers, trusts, duties,
authority and title of its predecessor; but such predecessor shall,
nevertheless, on the written request of the Majority Holders, the Company or
the successor trustee or trustees, execute and deliver an instrument
transferring to such successor or successors all the estates, properties,
rights, powers, trusts, duties, authority and title of such predecessor or
predecessors hereunder and shall deliver all securities and moneys held by it
to such successor trustee or trustees. Should any deed, conveyance or other
instrument in writing from the Company be required by any successor trustee or
trustees for more fully and certainly vesting in such successor trustee or
trustees the estates, properties, rights, powers, trusts, duties, authority and
title vested or intended to be vested in the predecessor trustee or trustees,
any and all such deeds, conveyances and other instruments in writing shall, on
request of such successor trustee or trustees, be executed, acknowledged and
delivered by the Company.

                  (d)      Any required filing for record of the instrument
appointing a successor trustee or trustees as hereinabove provided shall be at
the expense of the Company. The resignation of any trustee or trustees and the
instrument or instruments removing any trustee or trustees, together with all
other instruments, deeds and conveyances provided for in this Section 5 shall,
if permitted by law, be forthwith recorded, registered and filed by and at the
expense of the Company, wherever this Agreement is recorded, registered and
filed.

                  5.8      Status of Successors to the Trustee. Except as
permitted by Section 5.7, every successor to the Trustee appointed pursuant to
Section 5.7 shall be a bank or trust company in good standing and having power
so to act, incorporated under the laws of the United States or any State
thereof or the District of Columbia, and having its principal corporate trust
office within the 48 contiguous States, and shall also have capital, surplus
and undivided profits of not less than $100,000,000, if there be such an
institution with such capital, surplus and undivided profits willing, qualified
and able to accept the trust upon reasonable or customary terms.

                  5.9      Merger of the Trustee. Any corporation into which
the Trustee may be merged, or with which it may be consolidated, or any
corporation resulting from any merger or consolidation to which the Trustee
shall be a party, shall be Trustee under this Agreement without the execution
or filing of any paper or any further act on the part of the parties hereto.

                  5.10     Co-Trustee, Separate Trustee. (a) If at any time or
times it shall be necessary or prudent in order to conform to any law of any
jurisdiction in which any of the Collateral shall be located, or the Trustee
shall be advised by counsel, satisfactory to it, that it is so necessary or
prudent in the interest of the Holders, or the Majority Holders shall in
writing so request the Trustee and the Company, or the Trustee shall deem it
desirable for its own protection in the performance of its duties hereunder,
the Trustee and the Company shall execute and deliver all instruments and
agreements necessary or proper to constitute another bank or trust company, or
one or more persons approved by the Trustee and the Company, either to act as
co-trustee or co-trustees of all or any of the Collateral, jointly with the
Trustee originally named herein or any successor or successors, or to act as
separate trustee or trustees of any such property. In the event the Company
shall not have joined in the execution of such instruments and agreements
within 30 days after the receipt of a written request from the Trustee so to
do, or in case an Actionable Default shall have occurred and be continuing, the
Trustee may act under the foregoing


<PAGE>   15

provisions of this Section 5.10 without the concurrence of the Company, and the
Company hereby appoints the Trustee as its agent and attorney to act for it
under the foregoing provisions of this Section 5.10 in either of such
contingencies.

                  (b)      Every separate trustee and every co-trustee, other
than any trustee that may be appointed as successor to the Trustee, shall, to
the extent permitted by law, be appointed and act and be such, subject to the
following provisions and conditions, namely:

                           (i)      all rights, powers, duties and obligations
         conferred upon the Trustee in respect of the custody, control and
         management of moneys, papers or securities shall be exercised solely
         by the Trustee, or its successors as Trustee hereunder;

                           (ii) all rights, powers, duties and obligations
         conferred or imposed upon the Trustee hereunder shall be conferred or
         imposed and exercised or performed by the Trustee and such separate
         trustee or separate trustees or co-trustee or co-trustees, jointly, as
         shall be provided in the instrument appointing such separate trustee
         or separate trustees or co-trustee or co-trustees, except to the
         extent that under any law of any jurisdiction in which any particular
         act or acts are to be performed the Trustee shall be incompetent or
         unqualified to perform such act or acts, in which event such rights,
         powers, duties and obligations shall be exercised and performed by
         such separate trustee or separate trustees or co-trustee or
         co-trustees;

                           (iii) no power given hereby to, or that it is
         provided hereby may be exercised by, any such co-trustee or
         co-trustees or separate trustee or separate trustees, shall be
         exercised hereunder by such co-trustee or co-trustees or separate
         trustee or separate trustees, except jointly with, or with the consent
         in writing of, the Trustee, anything herein contained to the contrary
         notwithstanding;

                           (iv) no trustee hereunder shall be personally liable
         by reason of any act or omission of any other trustee hereunder; and

                           (v) the Company and the Trustee, at any time by an
         instrument in writing, executed by them, may accept the resignation of
         or remove any such separate trustee or co-trustee, and in that case,
         by an instrument in writing executed by the Company and the Trustee
         jointly, may appoint a successor to such separate trustee or
         co-trustee, as the case may be, anything herein contained to the
         contrary notwithstanding. In the event that the Company shall not have
         joined in the execution of any such instrument within ten days after
         the receipt of a written request from the Trustee so to do, or in case
         an Actionable Default shall have occurred and be continuing, the
         Trustee shall have the power to accept the resignation of or remove
         any such separate trustee or co-trustee and to appoint a successor
         without the concurrence of the Company, the Company hereby appointing
         the Trustee its agent and attorney to act for it in such connection in
         either of such contingencies. In the event that the Trustee shall have
         appointed a separate trustee or separate trustees or co-trustee or
         co-trustees as above provided, it may at any time, by an instrument in
         writing, accept the resignation of or remove any such separate trustee
         or co-trustee, the successor to any such separate trustee or
         co-trustee to be appointed by the Company and the Trustee, or by the
         Trustee alone, as provided in this Section 5.10.


<PAGE>   16

                                   SECTION 6

                             RELEASE OF COLLATERAL

                  6.1      Conditions to Release; Release Procedure. (a)
Subject to Section 6.1(b), the Collateral shall be released on the earliest of
the dates listed below:

                           (i)      the date on which the Trustee and the
         Public Trustee shall have received written notice from the
         Administrative Agent that (A) no Advances (as defined in the Credit
         Agreement) or any of the other Obligations (as defined in the Credit
         Agreement) of a Loan Party (as defined in the Credit Agreement) under
         or in respect of the Loan Documents (as defined in the Credit
         Agreement) shall remain unpaid, (B) no Letter of Credit (as defined in
         the Credit Agreement) shall remain outstanding and (C) no Lender Party
         (as defined in the Credit Agreement) shall have any Commitment (as
         defined in the Credit Agreement) under the Credit Agreement; or

                           (ii)     the date on which the Trustee shall have
         received written directions from the Administrative Agent directing
         the Trustee to release the Collateral (with a copy of such directions
         to be sent coincidentally to the Public Trustee).

                  (b)      The Collateral shall not be released unless and
until all Trustee's Fees shall have been paid in full.

                  (c)      Upon the release of the Collateral, all right, title
and interest of the Trustee in, to and under the Trust Estate, the Collateral
and the Security Documents shall terminate and shall revert to the Company, its
successors and assigns, and the estate, right, title and interest of the
Trustee therein shall thereupon cease, determine and become void; and in such
case, upon the written request of the Company, its successors or assigns, and
at the cost and expense of the Company, its successors or assigns, the Trustee
shall execute a satisfaction of the Security Documents and such instruments as
are necessary or desirable to terminate and remove of record any documents
constituting public notice of the Security Documents and the security interests
and assignments granted thereunder and shall assign and transfer, or cause to
be assigned and transferred, and shall deliver or cause to be delivered to the
Company, all property, including all moneys, instruments and securities, of the
Company then held by the Trustee. The cancellation and satisfaction of the
Security Documents shall be without prejudice to the rights of the Trustee or
any successor trustee to charge and be reimbursed for any expenditures that it
may thereafter incur in connection therewith.

                                   SECTION 7

                                 MISCELLANEOUS

                  7.1      Amendments, Supplements and Waivers. (a) With the
written consent of the Administrative Agent and the Public Trustee, the Trustee
and the Company may, from time to time, enter into written agreements
supplemental hereto for the purpose of adding to or waiving any provision of
this Agreement or any Security Document or changing in any manner the rights of
the Trustee, the Holders or the Company hereunder or thereunder; provided,
however, that no such supplemental agreement shall:


<PAGE>   17

                           (i)      amend, modify or waive any provision of
         this Section 7.1 without the written consent of each Holder,

                           (ii)     reduce the percentage specified in the
         definition of Majority Holders without the written consent of all the
         Holders,

                           (iii)    amend, modify or waive any provision of
         Section 3.4, 3.5 or 6.1 or the definition of the term "Secured Debt"
         without the written consent of any Holder whose rights would be
         adversely affected thereby,

                           (iv)     amend, modify or waive any provision of
         Section 5 or alter the duties or obligations of the Trustee hereunder
         without the written consent of the Trustee.

Any such supplemental agreement shall be binding upon the Company, the Holders
and the Trustee and their respective successors. The Trustee shall not enter
into any such supplemental agreement unless it shall have received a
certificate of a Responsible Officer of the Company to the effect that such
supplemental agreement will not result in a breach of any provision or covenant
contained in the Indenture.

                  (b)      Without the consent of any Holders, the Trustee and
the Company, at any time and from time to time, may enter into additional
pledge or security agreements or one or more agreements supplemental hereto or
to any Security Document, in form satisfactory to the Trustee,

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

                           (ii)     to mortgage, pledge or grant a security
         interest in any property or assets that are required to be mortgaged
         or pledged, or in which a security interest is required to be granted,
         to the Trustee pursuant to the Debt Instrument or any Security
         Document;

                           (iii)    to cure any ambiguity, to correct or
         supplement any provision herein or in any Security Document that may
         be defective or inconsistent with any other provision herein or
         therein, or to make any other provisions with respect to matters or
         questions arising hereunder or under any Security Document that shall
         not be inconsistent with any provision hereof or of any Security
         Document.

                  7.2      Notices. All notices, requests, demands and other
communications provided for or permitted hereunder shall be in writing
(including telecopy communications) and shall be sent by mail, telecopier or
hand delivery:

                           (a)      If to the Company, to it at its address at:
         3000 Galleria Tower, Suite 1000, Birmingham, Alabama 35244, Telecopier
         No. (205) 733-9780 or at such other address as shall be designated by
         it in a written notice to the Trustee.

                           (b)      If to the Trustee, to it at its address at:
         135 South LaSalle Street, Suite 1960, Chicago, Illinois 60603,
         Attention: Corporate Trust Services Division, Telecopier No: (312)
         904-2236 or at such other address as shall be designated by it in a
         written notice to the Company.


<PAGE>   18

                           (c)      If to the Public Trustee, to it at its
         address at 180 East Fifth Street -- 2nd Floor, St. Paul, Minnesota
         55101, Attention: Mr. Timothy J. Sandell, Telecopier No. (651)
         244-5847, or at such other address as shall be designated by it in
         writing to the Trustee.

                           (d)      If to the Administrative Agent, to it at
         its address at Independence Center, 101 North Tryon Street, 15th
         Floor, Charlotte, North Carolina 28255, Attention: Corporate Credit
         Services, Telecopier No. (704) 386-9923 or at such other address as
         shall be designated by it in writing to the Trustee.

                           (e)      Any notice given to any Holder shall also
         be given to the Public Trustee and the Administrative Agent.

All such notices, requests, demands and communications shall be deemed to have
been duly given or made, when delivered by hand or five Business Days after
being deposited in the mail, postage prepaid, or when telecopied, receipt
acknowledged; provided, however, that any notice, request, demand or other
communication to the Trustee shall not be effective until received.

                  7.3      Headings. Section, subsection and other headings
used in this Agreement are for convenience only and shall not affect the
construction of this Agreement.

                  7.4      Severability. Any provision of this Agreement that
is prohibited or unenforceable in any jurisdiction shall not invalidate the
remaining provisions hereof, and any such prohibition or unenforceability in
any jurisdiction shall not invalidate or render unenforceable such provision in
any other jurisdiction.

                  7.5      Treatment of Payee or Indorsee by Trustee. (a) The
Trustee may treat the registered holder of any registered note, and the payee
or indorsee of any note or debenture that is not registered, as the absolute
owner thereof for all purposes hereunder and shall not be affected by any
notice to the contrary, whether such promissory note or debenture shall be past
due or not.

                  (b)      Any person, firm, corporation or other entity that
shall be designated as the duly authorized representative of one or more
Holders of Secured Debt to act as such in connection with any matters
pertaining to this Agreement or any Security Document or the Collateral shall
present to the Trustee such documents, including, without limitation, opinions
of counsel, as the Trustee may reasonably require, in order to demonstrate to
the Trustee the authority of such person, firm, corporation or other entity to
act as the representative of such Holders.

                  7.6      Dealings with the Company. (a) Upon any application
or demand by the Company to the Trustee to take or permit any action under any
of the provisions of this Agreement, the Company shall furnish to the Trustee a
certificate of a Responsible Officer stating that all conditions precedent, if
any, provided for in this Agreement relating to the proposed action have been
complied with, except that in the case of any such application or demand as to
which the furnishing of such documents is specifically required by any
provision of this Agreement relating to such particular application or demand,
no additional certificate or opinion need be furnished.

                  (b)      Any opinion of counsel may be based, insofar as it
relates to factual matters, upon a certificate of a Responsible Officer filed
with the Trustee.


<PAGE>   19

                  7.7      Claims Against the Trustee. Any claims or causes of
action that the Administrative Agent, the Private Lenders, the Public Trustee
or the Company shall have against the Trustee shall survive the termination of
this Agreement and the release of the Collateral hereunder.

                  7.8      Binding Effect. This Agreement shall be binding upon
and inure to the benefit of each of the parties hereto, the Holders, and their
respective successors and assigns, and nothing herein or in any Security
Document is intended or shall be construed to give any other person any right,
remedy or claim under, to or in respect of this Agreement, any Security
Document, the Collateral or the Trust Estate.

                  7.9      Governing Law. This Agreement shall be governed by,
and construed and interpreted in accordance with, the laws of the State of
Illinois and any action alleging any breach by the Trustee of its duties
hereunder, whether by act or omission or anticipatory, shall be prosecuted only
in the courts of the State of Illinois.

                  7.10     Counterparts. This Agreement may be executed in
separate counterparts, each of which shall be an original and all of which
taken together shall constitute one and the same instrument.

             [The remainder of this page intentionally left blank.]


<PAGE>   20


                  IN WITNESS WHEREOF, the parties hereto have executed this
Agreement or caused this Agreement to be duly executed by their respective
officers thereunto duly authorized as of the day and year first above written.

                                       CAREMARK RX, INC.


                                               /s/ Peter J. Clemens IV
                                       -------------------------------------
                                       By:     Peter J. Clemens IV
                                       Title:  SVP Finance & Treasurer


                                       LASALLE BANK NATIONAL ASSOCIATION,
                                                AS TRUSTEE



                                                /s/ Russell C. Bergman
                                       -------------------------------------
                                       By:      Russell C. Bergman
                                       Title:   Vice President


<PAGE>   21

CAREMARK RX, INC. TRUST AGREEMENT   Acknowledgment

STATE OF   ALABAMA    )
         -------------
COUNTY OF JEFFERSON   ) ss:
         -------------

                  On the 5 day of November, 1999, before me personally came
Peter J. Clemens , to me personally known and known to me to be the person
described in and who executed the foregoing instrument as agent of CAREMARK RX,
INC., and who, being by me duty sworn, did depose and say that s/he resides at
2547 Willow Brook Cir.; that s/he is SVP Finance & Treasurer of Caremark Rx,
one of the corporations described in and that executed the foregoing
instrument; that said instrument was signed on behalf of said corporation by
order of its Board of Directors; that s/he signed his/her name thereto by like
order, and that s/he acknowledged said instrument to be the free act and deed
of said corporation.

                                                      /s/ Andrea Storch
                                                -------------------------------
                                                   Notary Public
                                                 Exp: 4-2-02
[Seal]

<PAGE>   22

CAREMARK RX, INC. TRUST AGREEMENT   Acknowledgment

STATE OF ILLINOIS   )
         -----------
COUNTY OF COOK    ) ss:
         ---------

                  On the 4th day of November, 1999, before me personally came
Russell C. Bergman, to me personally known and known to me to be the person
described in and who executed the foregoing instrument as Vice President of
LASALLE BANK NATIONAL ASSOCIATION, and who, being by me duty sworn, did depose
and say that s/he resides at Frankfort, Illinois; that s/he is Vice
President of LaSalle Bank National Association, one of the corporations
described in and that executed the foregoing instrument; that said instrument
was signed on behalf of said corporation by order of its Board of Directors;
that s/he signed his/her name thereto by like order, and that s/he acknowledged
said instrument to be the free act and deed of said corporation.

                                              /s/ Mary Ann Kicmal
                                       -------------------------------
                                            Notary Public
                                       Exp:  12/01/2001
[Seal]