EXHIBIT 10

                       SECOND AMENDMENT TO LOAN AGREEMENT


            THIS SECOND AMENDMENT ("Second Amendment") dated as of the 15th day
of September, 2002, to the Loan Agreement (the "Loan Agreement"), made and
entered into as of September 15, 2001, by and among SUMMIT BANCSHARES, INC., a
Texas corporation, (hereinafter called "Borrower"), SUMMIT DELAWARE FINANCIAL
CORPORATION, a Delaware corporation, (hereinafter called "SDFC") and THE FROST
NATIONAL BANK, a national banking association (hereinafter called "Lender"). All
capitalized terms not otherwise defined herein shall have the meaning ascribed
to each of them in the Loan Agreement.

                              W I T N E S S E T H:

            WHEREAS, Borrower executed the Loan Agreement to govern those two
certain promissory notes from Lender, specifically, a $10,000,000.00 Acquisition
Note and a $1,000,000.00 Liquidity Note (collectively, the "Notes").

            WHEREAS, Borrower executed the First Amendment to Loan Agreement on
March 8, 2002 ("First Amendment") which modified the Loan Agreement to evidence
the Borrower's formation of SDFC to own the Bank; and

            WHEREAS, the Borrower now desires to renew and extend the unpaid
principal balance of the Notes; and

            WHEREAS, the Lender agrees to renew and extend the Notes all as
hereinafter provided.

            NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, Borrower and Lender do hereby agree as follows:

                                    ARTICLE I

                           Amendment to Loan Agreement

            1.1 Amendment to Notes. As of the effective date hereof, the
Borrower has zero outstanding under the Acquisition Note and the Liquidity Note.
The Borrower desires to renew these credit facilities by the execution of
another Acquisition Note and Liquidity Note extending the original payment terms
and the maturity date by one year. Accordingly, Sections 2.02(a) and (b) of the
Loan Agreement shall be, and are hereby, amended to read in their entirety as
follows:

                        "2.02 (a) Acquisition Note. From Closing Date and
            continuing at all times through September 15, 2003 (the "Revolving
            Credit Period") the Loan evidenced by the Acquisition Note shall be
            a revolving credit facility which will allow the Borrower to request
            such amounts as Borrower may elect from time to time (each such
            amount being herein called an "Advance") so long as the aggregate
            amount of Advances outstanding at any time under the Acquisition
            Note does not exceed Ten Million and NO/100 Dollars ($10,000,000.00)
            provided however, the minimum Advance must be at least $500,000.00.


SECOND AMENDMENT TO LOAN AGREEMENT -- Page 1


            The Borrower shall have the right to borrow, repay, and borrow again
            under the credit facility. Interest shall be due and payable
            quarterly and shall accrue at the election of the Borrower (which
            election shall be made on the date of the first Advance) at either
            LIBOR plus 200 basis points or the Prime Rate. The outstanding
            principal balance of the Acquisition Note on September 15, 2003
            shall convert to a term facility (the "Term Period") and shall be
            payable in accordance with the terms of the Acquisition Note.

                        (b) Liquidity Note. The Liquidity Note shall be due and
            payable as follows: during the Revolving Credit Period, the Loan
            evidenced by the Liquidity Note shall be a revolving credit facility
            which will allow the Borrower to request such amounts as Borrower
            may elect from time to time (each such amount being herein called an
            "Advance") so long as the aggregate amount of Advances outstanding
            at any time under the Liquidity Note does not exceed One Million and
            NO/100 Dollars ($1,000,000.00) provided however, the minimum Advance
            must be at least $50,000.00. The Borrower shall have the right to
            borrow, repay, and borrow again under the credit facility. Interest
            shall be due and payable quarterly and shall accrue at the Prime
            Rate. The outstanding principal balance of the Liquidity Note on
            September 15, 2003 shall convert to a term facility (the "Term
            Period") and shall be payable in accordance with the terms of the
            Liquidity Note.

                                   ARTICLE II

                           Conditions of Effectiveness

            2.1 Effective Date. This Second Amendment shall become effective as
and when, and only when, Lender shall have received counterparts of this Second
Amendment executed and delivered by Borrower and when each of the following
conditions shall have been met, all in form, substance, and date satisfactory to
Lender:

                        (a) Renewal Notes. Borrower shall have executed and
            delivered to Lender a new Acquisition Note and new Liquidity Note,
            each payable to the order of Lender as set forth therein, each duly
            executed on behalf of the Borrower, dated effective September 15,
            2002 in the principal amounts of $10,000,000.00 and $1,000,000.00,
            respectively.

                        (b) Additional Loan Documents. Borrower and SDFC shall
            have executed and delivered to Lender such other documents as shall
            have been requested by Lender to secure payment of the Obligations
            of Borrower, all in form satisfactory to Lender and its counsel.

                                   ARTICLE III

                         Representations and Warranties

            3.1 Representations and Warranties of the Borrower. In order to
induce Lender to enter into this Second Amendment, Borrower represents and
warrants the following:

                        (a) Borrower has the corporate power to execute and
            deliver this Second Amendment and the other Loan Documents executed
            by it and to perform all of its obligations in connection herewith
            and therewith.

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                        (b) The execution and delivery by Borrower of this
            Second Amendment and other Loan Documents executed by it and the
            performance of its obligations in connection herewith and therewith:
            (i) have been duly authorized or will be duly ratified and affirmed
            by all requisite corporate action; (ii) will not violate any
            provision of law, any order of any court or agency of government or
            the Articles of Incorporation or Bylaws of such entity; (iii) will
            not be in conflict with, result in a breach of or constitute (alone
            or with due notice or lapse of time or both) a default under any
            indenture, agreement or other instrument; and (iv) will not require
            any registration with, consent or approval of or other action by any
            federal, state, provincial or other governmental authority or
            regulatory body.

                        (c) There is no action, suit or proceeding at law or in
            equity or by or before any governmental instrumentality or other
            agency or regulatory authority now pending or, to the knowledge of
            Borrower, threatened against or affecting Borrower or any properties
            or rights of Borrower or involving this Second Amendment or the
            transactions contemplated hereby which, if adversely determined,
            would materially impair the right of Borrower, to carry on business
            substantially as now conducted or materially and adversely affect
            the financial condition of Borrower or materially and adversely
            affect the ability of Borrower to consummate the transactions
            contemplated by this Second Amendment.

                        (d) The representations and warranties of Borrower
            contained in the Loan Agreement, this Second Amendment and any other
            Loan Document securing Borrower's Obligations and indebtedness to
            Lender are correct and accurate on and as of the date hereof as
            though made on and as of the date hereof, except to the extent that
            the facts upon which such representations are based have been
            changed by the transactions herein contemplated.

            3.2 Representations and Warranties of SDFC. In order to induce
Lender to enter into this Second Amendment, SDFC represents and warrants the
following:

                        (a) SDFC has the corporate power to execute and deliver
            this Second Amendment and the other Loan Documents executed by it
            and to perform all of its obligations in connection herewith and
            therewith.

                        (b) The execution and delivery by SDFC of this Second
            Amendment and other Loan Documents executed by it and the
            performance of its obligations in connection herewith and therewith:
            (i) have been duly authorized or will be duly ratified and affirmed
            by all requisite corporate action; (ii) will not violate any
            provision of law, any order of any court or agency of government or
            the Articles of Incorporation or Bylaws of such entity; (iii) will
            not be in conflict with, result in a breach of or constitute (alone
            or with due notice or lapse of time or both) a default under any
            indenture, agreement or other instrument; and (iv) will not require
            any registration with, consent or approval of or other action by any
            federal, state, provincial or other governmental authority or
            regulatory body.


SECOND AMENDMENT TO LOAN AGREEMENT -- Page 3


                        (c) There is no action, suit or proceeding at law or in
            equity or by or before any governmental instrumentality or other
            agency or regulatory authority now pending or, to the knowledge of
            SDFC, threatened against or affecting SDFC or any properties or
            rights of SDFC or involving this Second Amendment or the
            transactions contemplated hereby which, if adversely determined,
            would materially impair the right of SDFC, to carry on business
            substantially as now conducted or materially and adversely affect
            the financial condition of SDFC or materially and adversely affect
            the ability of SDFC to consummate the transactions contemplated by
            this Second Amendment.

                                   ARTICLE IV

                      Ratification of Obligations and Liens

            4.1 Ratification of Obligation. The Borrower and SDFC do each hereby
acknowledge, ratify and confirm their obligations to Lender as evidenced by the
Loan Agreement (as amended by the First Amendment and this Second Amendment) and
all other Loan Documents, as modified by the transactions herein contemplated.

            4.2 Valid Liens. Borrower and SDFC hereby acknowledge and agree that
the liens and security interests of the Loan Documents, as modified by the
transactions herein contemplated, are valid and subsisting liens and security
interests and are superior to all liens and security interests other than those
exceptions approved by Lender in writing. Nothing herein contained shall affect
or impair the validity or priority of the liens and security interests under the
Loan Documents.

            4.3 Ratification of Agreements. The Loan Agreement (as amended by
the First Amendment), this Second Amendment, and each other Loan Document, as
hereby amended, is acknowledged, ratified and confirmed in all respects as being
valid, existing, and of full force and effect. Any reference to the Loan
Agreement in any Loan Document shall be deemed to be a reference to the Loan
Agreement (as previously amended) as amended by this Second Amendment. The
execution, delivery and effectiveness of this Second Amendment shall not, except
as expressly provided herein, operate as a waiver of any right, power or remedy
of Lender under the Loan Agreement, nor constitute a waiver of any provision of
the Loan Agreement. The Borrower acknowledges, ratifies and confirms that the
collateral securing the Loan secures all of the indebtedness of the Borrower,
including without limitation, the Notes.

                                    ARTICLE V

                                  Miscellaneous

            5.1 Survival of Agreements. All representations, warranties,
covenants and agreements of Borrower, herein or in any other Loan Document shall
survive the execution and delivery of this Second Amendment, and the other Loan
Documents and the performance hereof and thereof, including without limitation
the making or granting of the Loan and the delivery of the Notes and all other
Loan Documents, and shall further survive until all of Borrower's Obligations to
Lender are paid in full. All statements and agreements contained in any
certificate or instrument delivered by Borrower hereunder or under the Loan
Documents to Lender shall be deemed to constitute the respective representations
and warranties by Borrower and/or respective agreements and covenants of
Borrower under this Second Amendment and under the Loan Agreement.

SECOND AMENDMENT TO LOAN AGREEMENT -- Page 4


            5.2 Loan Document. This Second Amendment, the Notes, the Guaranty
Agreement, the Pledge Agreements and each other Loan Documents executed in
connection herewith are each a Loan Document and all provisions in the Loan
Agreement, as amended, pertaining to Loan Documents apply hereto and thereto.

            5.3 Governing Law. This Second Amendment shall be governed by and
construed in all respects in accordance with the laws of the State of Texas and
any applicable laws of the United States of America, including construction,
validity and performance.

            5.4 Counterparts. This Second Amendment may be separately executed
in any number of counterparts and by different parties hereto in separate
counterparts, each of which when so executed shall be deemed to constitute one
and the same Second Amendment.

            5.5 Release of Claims. Borrower by its execution of this Second
Amendment, hereby declares that it has no set-offs, counterclaims, defenses or
other causes of action against Lender arising out of the Loan, the renewal,
modification and extension of the Loan, any documents mentioned herein or
otherwise; and, to the extent any such setoffs, counterclaims, defenses or other
causes of action which may exist, whether known or unknown, such items are
hereby expressly waived and released by Borrower.

            5.6 Attorneys' Fees. Borrower hereby agrees to pay to Lender, upon
demand, the reasonable attorneys' fees and expenses of Lender's counsel, filing
and recording fees and other reasonable expenses incurred by Lender in
connection with this Second Amendment. Borrower also agrees to provide to Lender
such other documents and instruments as Lender may reasonably request in
connection with the renewal, extension and modification of the Loans mentioned
herein.

            5.7 ENTIRE AGREEMENT. THIS SECOND AMENDMENT, TOGETHER WITH ANY LOAN
DOCUMENTS EXECUTED IN CONNECTION HEREWITH, CONTAINS THE ENTIRE AGREEMENT BETWEEN
THE PARTIES HERETO RELATING TO THE SUBJECT MATTER HEREOF AND THEREOF AND ALL
PRIOR AGREEMENTS RELATIVE THERETO WHICH ARE NOT CONTAINED HEREIN OR THEREIN ARE
TERMINATED. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES. THIS
SECOND AMENDMENT, AND THE LOAN DOCUMENTS MAY BE AMENDED, REVISED, WAIVED,
DISCHARGED, RELEASED OR TERMINATED ONLY BY A WRITTEN INSTRUMENT OR INSTRUMENTS,
EXECUTED BY THE PARTY AGAINST WHICH ENFORCEMENT OF THE AMENDMENT, REVISION,
WAIVER, DISCHARGE, RELEASE OR TERMINATION IS ASSERTED. ANY ALLEGED AMENDMENT,
REVISION, WAIVER, DISCHARGE, RELEASE OR TERMINATION WHICH IS NOT SO DOCUMENTED
SHALL NOT BE EFFECTIVE AS TO ANY PARTY.


SECOND AMENDMENT TO LOAN AGREEMENT -- Page 5



            IN WITNESS WHEREOF, this Second Amendment is executed effective as
of the date first written above.


BORROWER:                           SUMMIT BANCSHARES, INC.


                                    By: /s/ Bob G. Scott
                                        ----------------------------------------
                                    Its: Executive Vice President
                                          --------------------------------------


LENDER:                             THE FROST NATIONAL BANK

                                    By: /s/ Jerry L. Crutsinger
                                        ----------------------------------------
                                        Jerry L. Crutsinger, Senior Vice
                                        President


GUARANTOR:                          SUMMIT DELAWARE FINANCIAL CORPORATION


                                    By: /s/ Bob G. Scott
                                        ----------------------------------------
                                    Its: Executive Vice President
                                         ---------------------------------------


SECOND AMENDMENT TO LOAN AGREEMENT -- Page 6