<PAGE>   1
                             ACQUISITION AGREEMENT
                                  BY AND AMONG
                          JACKSONVILLE BANCORP, INC.,
                            JACKSONVILLE IHC, INC.,
                                      AND
                   JACKSONVILLE SAVINGS AND LOAN ASSOCIATION
<PAGE>   2
                             ACQUISITION AGREEMENT

         ACQUISITION AGREEMENT, dated as of May 6, 1997 ("Agreement"), is by
and among Jacksonville Bancorp, Inc. ("Bancorp"), Jacksonville Savings and Loan
Association, a Texas-chartered savings association, which will be converting to
a Texas-chartered savings bank under the name "Jacksonville Savings Bank, SSB",
whose accounts are and will continue to be insured by the Savings Association
Insurance Fund ("SAIF") administered by the Federal Deposit Insurance
Corporation ("FDIC") (hereinafter referred to as "Jacksonville" whether in its
savings association or savings bank form), and Jacksonville IHC, Inc., a
Delaware-chartered business corporation ("Holding Company"), all of the
aforesaid entities collectively referred to herein as the "Parties" or
individually as a "Party."

                                  WITNESSETH:

         WHEREAS, the Boards of Directors of Jacksonville have determined that
it is in the best interests of Jacksonville and their sole stockholder,
Bancorp, for the ownership structure to be reorganized so that all of the
voting common stock is held directly by a Delaware-chartered holding company,
in accordance with the terms and conditions of this Agreement; and

         WHEREAS, the acquisition is to be accomplished as follows:  the
Holding Company, a Delaware business corporation which is also a subsidiary of
the Bancorp, will become the sole stockholder of Jacksonville through the
contribution by Bancorp of 100% of the voting common stock of Jacksonville to
Holding Company.

         NOW, THEREFORE, in consideration of the premises and of the mutual
agreements herein contained, and in accordance with Texas and federal law and
regulations, Bancorp, Jacksonville and the Holding Company hereby agree that,
subject to the conditions hereinafter set forth, Bancorp will contribute to
Holding Company all the outstanding shares of Jacksonville, wherein
Jacksonville will become the wholly-owned subsidiary of the Holding Company.
The terms and conditions of the Acquisition shall be as follows:

         1.      REGULATORY APPROVALS.     (a)  The Acquisition shall not
become effective until this Agreement and the transactions contemplated hereby
have received the approval, if required, of the Commissioner of the Texas
Savings and Loan Department (the "Department"), the Federal Deposit Insurance
Corporation (the "FDIC"), the Office of Thrift Supervision (the "OTS"), the
Board of Governors of the Federal Reserve System ("FRB") and all other
regulatory agencies having jurisdiction over the Acquisition, if any.

                 (b)  Bancorp, Jacksonville and the Holding Company shall have
obtained all other consents, permissions and approvals required, appropriate or
deemed necessary, from any other governmental agencies or other third parties
and shall have taken all actions required by law or agreement, by Bancorp,
Jacksonville or the Holding Company, prior to the consummation of the
Agreement.
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Acquisition Agreement
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         2.      EFFECTIVE DATE.  The effective date of the Acquisition
("Effective Date") shall be the date as soon as practicable after the issuance
and/or execution by the Department, the OTS, FDIC, FRB and any other federal or
state regulatory agencies, of all approvals, certificates and documents as may
be required in order to cause Acquisition to become effective.

         3.      STOCKHOLDER APPROVAL.  The prior written consent of Bancorp,
the sole stockholder of Jacksonville and the Holding Company, shall be required
to approve this Agreement.

         4.      COMMON STOCK OF JACKSONVILLE.  All of the issued and
outstanding shares of Jacksonville voting common stock owned by Bancorp
immediately prior to the Acquisition shall be contributed by Bancorp to the
Holding Company, resulting in the Holding Company owning one hundred percent
(100%) of the issued and outstanding voting common stock of Jacksonville.

         5.      DEPOSITS.  All deposit accounts of Jacksonville shall remain
deposits therein without change in their respective terms, interest rates,
maturities, minimum required balances or withdrawal values following the
Acquisition and will continue to issue deposit accounts on the same basis as
immediately prior to the Effective Date.  After the Effective Date, all
deposits held by Jacksonville shall continue to be insured by the SAIF.

         6.      INCOME TAX MATTERS.  The parties hereto shall have received an
opinion of counsel or its independent auditors, satisfactory to them in form
and substance, with respect to the federal income tax consequences of the
Agreement and the formation of a holding company, as contemplated herein.

         7.      ABANDONMENT OF AGREEMENT.  (a)  This Agreement may be
abandoned by Jacksonville, at any time before the Effective Date in the event
that (a) any action, suit, proceeding or claim has been instituted, made or
threatened relating to this Agreement which shall make consummation of the
Acquisition inadvisable in its opinion; or (b) for any other reason,
consummation of the Acquisition contemplated by this Agreement is inadvisable
in its opinion.

                 (b)      Such abandonment shall be effective by written notice
by Jacksonville to the other Parties.  Upon the giving of such notice, this
Agreement shall be terminated and there shall be no liability hereunder or on
account of such termination on the part of Bancorp, Jacksonville or the Holding
Company or the directors, officers, employees, agents, or stockholders of any
of them.  In the event of abandonment of the Agreement, Jacksonville shall pay
fees and expenses incurred by itself, Bancorp and Holding Company in connection
with the Agreement and the Acquisition contemplated thereby.  Jacksonville
shall promptly furnish a copy of such written notice to the Department, the
FDIC, the OTS, and the FRB.
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Acquisition Agreement
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         8.      AMENDMENT OF THE AGREEMENT.  This Agreement may be amended or
modified at any time by mutual agreement of the Boards of Directors of Bancorp,
Jacksonville and the Holding Company, in any respect, provided that the sole
stockholder subsequently approves of such amendment or modification.

         9.      GOVERNING LAW.  This Agreement is made pursuant to, and shall
be construed and be governed by, the laws of the State of Texas and of the
United States, and the rules and regulations promulgated thereunder, including
without limitation, the rules and regulations of the Department, the FDIC, the
OTS, and the FRB.  In the event of a conflict, federal law will apply.

         10.     ASSIGNMENT.  The rights and obligations of the Parties hereto
may not be assigned without the prior written consent of the other Parties.
This Agreement shall be binding upon, and shall insure to the benefit of, the
Parties and their respective successors and permitted assignees.

         23.     EXECUTION BY INTERIM.  Jacksonville and the Holding Company
acknowledge that as of the date hereof, Jacksonville Savings Bank, SSB is in
organization and has not received its Articles of Incorporation from the
Department.  Therefore, Jacksonville Savings Bank, SSB does not have the legal
capacity to execute this Agreement as of the date hereof.  Bancorp,
Jacksonville and the Holding Company agree to be bound by this Agreement
notwithstanding the lack of execution by Jacksonville Savings Bank, SSB.

         IN WITNESS WHEREOF, the Parties have caused this Agreement to be duly
executed on its behalf by its officers thereunto duly authorized, all as of the
date first above written.

                                       JACKSONVILLE BANCORP, INC.
                                       
                                       
                                       
                                       By:                                     
                                               --------------------------------
                                               Jerry M. Chancellor, President
                                       
                                       
                                       Attest:
                                       
                                       
                                                                               
                                       ----------------------------------------
                                       Sandra Thompson, Secretary
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Acquisition Agreement
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                                       JACKSONVILLE SAVINGS AND LOAN
                                         ASSOCIATION
                                       
                                       
                                       
                                       By:                                     
                                               --------------------------------
                                               Jerry M. Chancellor, President
                                       
                                       
                                       Attest:
                                       
                                       
                                                                               
                                       ----------------------------------------
                                       Sandra Thompson, Secretary
                                       
                                       
                                       
                                       JACKSONVILLE IHC, INC.
                                       
                                       
                                       By:                                     
                                               --------------------------------
                                               Jerry M. Chancellor, President
                                       
                                       Attest:
                                       
                                       
                                                                               
                                       ----------------------------------------
                                       Sandra Thompson, Secretary