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                                                                    EXHIBIT 10.2

                       SUPPLEMENT TO EMPLOYMENT AGREEMENT


         This Supplement to Employment Agreement (this "Supplement") is made as
of the 9th day of March, 1999, by and between United Bank (the "Bank") and
Robert R. Jones, III ("Jones"), and is joined by United Bancorporation of
Alabama, Inc. ("UBA").

         WHEREAS, the Bank and Jones are parties to that certain Employment
Agreement made and entered into as of January 1, 1998, (the "Employment
Agreement"); and

         WHEREAS, pursuant to the Employment Agreement UBA has granted options
to purchase Class A Common Stock of UBA ("Stock") to Jones pursuant to the 1998
Stock Option Plan of United Bancorporation of Alabama, Inc. (the "Plan"); and

         WHEREAS, the Stock Option Committee of the Board of Directors of UBA
(the "Committee"), which administers the Plan, has determined that certain
future grants of incentive stock options ("ISOs") should be made to Jones
pursuant to the Plan, and the respective Boards of Directors of UBA and the Bank
have approved such future grants; and

         WHEREAS, the Bank, Jones and UBA desire to make provisions for the
accelerated grant of such ISOs in certain circumstances, consistent with the
Plan and the objectives of the Employment Agreement.

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants herein contained and other good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the parties hereto
agree as follows:


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                  1. UBA agrees that no later than December 22 of each year
         beginning in 1999 and ending in 2002, UBA will grant an ISO covering
         two thousand forty (2,040) shares of Stock, pursuant to the Plan. Each
         such ISO grant will specify an exercise price equal to the then-current
         fair market value of Stock, and each such ISO will be exercisable in
         five equal installments, the first such installment becoming
         exercisable on the date of grant, and each of the four subsequent
         installments becoming exercisable on successive anniversaries of the
         date of grant. Each such ISO will otherwise contain terms and
         conditions equivalent to those set forth in the Incentive Stock Option
         Grant Agreement made by Jones and UBA as of December 22, 1998.

                  2. UBA further agrees that, with respect to any ISOs described
         in Section 1 above which have not been granted prior to a Change of
         Control (as defined in Section 21 of the Employment Agreement), UBA
         shall, as early as practicable in advance of the Change of Control and
         in any event as of the date immediately before the date on which the
         Change of Control occurs, grant to Jones all such ISOs which had not
         been previously granted, on the terms and conditions set forth above
         except that the exercise price for all such ISOs shall be the
         then-current fair market value of Stock, and that all such options
         shall be immediately exercisable as to all shares of Stock covered
         thereby.

                  3. The obligations of UBA to grant ISOs as set forth above are
         contingent upon stockholder approval of the Plan, and the obligation to
         grant any particular ISO is contingent upon the continued employment of
         Jones pursuant to the Employment Agreement at the time for such grant.


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         IN WITNESS WHEREOF, the Bank, Jones and UBA have duly executed this
Supplement to Employment Agreement as of the day and year above.

                                         UNITED BANK


                                         By: /s/ David D. Swift
                                            -----------------------------
                                         Its: Chairman 
                                              ---------------------------
Attest:


/s/ Charles E. Karrick
-------------------------
Its: Secretary

                                         UNITED BANCORPORATION OF ALABAMA, INC.


                                         By: /s/ H. Leon Esnuel
                                            -----------------------------
                                         Its: Chairman
                                              ---------------------------

Attest:


/s/ David D. Swift                                       
-------------------------
Its:  Secretary


                                         /s/ Robert R. Jones, III
                                        ---------------------------------
                                        Robert R. Jones, III


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