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                                                                   EXHIBIT 10.21

                       SIXTH AMENDMENT TO CREDIT AGREEMENT


         THIS SIXTH AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is entered
into as of October ___ 2001, among PMC CAPITAL, INC., a Florida corporation
("Borrower"), certain Lenders, and BANK ONE, NA, with its main office in
Chicago, Illinois, successor by merger to Bank One, Texas, N.A. ("Administrative
Agent").

                             PRELIMINARY STATEMENT:

         Borrower, Administrative Agent and Lenders are party to that certain
Credit Agreement (as renewed, extended, amended and restated, the "Credit
Agreement") dated as of March 22, 2000, pursuant to which the Lenders have made
and may hereafter make loans to Borrower. Borrower, Administrative Agent and
Lenders have agreed to amend the Credit Agreement in order to (i) extend the
maturity of the loan facility for an additional year, (ii) reduce the loan
commitment from $15,000,000 to $10,000,000, and (iii) provide for a $5,000,000
discretionary guidance line facility.

         Accordingly, for adequate and sufficient consideration, the receipt of
which is hereby acknowledged, Borrower, Administrative Agent and Lenders agree
as follows:

1. Defined Terms; References. Unless otherwise stated in this Amendment (a)
terms defined in the Credit Agreement have the same meanings when used in this
Amendment and (b) references to "Sections," "Schedules" and "Exhibits" are to
sections, schedules and exhibits to the Credit Agreement.

2. Amendments.

         (a) The defined term "Commitment" in Section 1.1 of the Credit
Agreement is amended in its entirety as follows:

             "Commitment" means in an amount (subject to reduction or
             cancellation as herein provided) equal to $10,000,000.

         (b) The defined term "Stated Termination Date" in Section 1.1 of the
Credit Agreement is amended in its entirety as follows:

             "Stated Termination Date" means, March 22, 2003.

         (c) A new Section 2.6 is hereby added to the Credit Agreement as
follows:

                  2.6. Discretionary Guidance Facility. Borrower may at any time
         submit to Administrative Agent a written notice requesting that Lenders
         increase the Commitment to an amount not to exceed $15,000,000.
         Administrative Agent and Lenders agree to use reasonable efforts to
         respond to Borrower indicating their approval or rejection of such
         request within thirty days of Administrative Agent's receipt of such
         written notice. If Administrative Agent and Lenders agree to increase
         the

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         Commitment pursuant to any such request by Borrower, Administrative
         Agent and Lenders may, in their sole and absolute discretion, specify
         the conditions applicable to their agreement to such increase, which
         may include, without limitation, the delivery to Administrative Agent
         and Lenders of such documents, instruments and assurances as
         Administrative Agent and Lenders deem necessary or appropriate to
         evidence such increase.

3. Conditions Precedent. Notwithstanding any contrary provisions, the foregoing
paragraphs in this Amendment are not effective unless and until (a) the
representations and warranties in this Amendment are true and correct, (b)
Administrative Agent receives counterparts of this Amendment executed by each
party named below.

4. Ratifications. This Amendment modifies and supersedes all inconsistent terms
and provisions of the Credit Documents, and except as expressly modified and
superseded by this Amendment, the Credit Documents are ratified and confirmed
and continue in full force and effect. Borrower, Administrative Agent and
Lenders agree that the Credit Documents, as amended by this Amendment, continue
to be legal, valid, binding and enforceable in accordance with their respective
terms.

5. Representations and Warranties. Borrower hereby represents and warrants to
Administrative Agent and Lenders that (a) this Amendment and any Credit
Documents to be delivered under this Amendment have been duly executed and
delivered by Borrower, (b) no action of, or filing with, any Governmental
Authority is required to authorize, or is otherwise required in connection with,
the execution, delivery, and performance by Borrower of this Amendment and any
Credit Document to be delivered under this Amendment, (c) this Amendment and any
Credit Documents to be delivered under this Amendment are valid and binding upon
Borrower and are enforceable against Borrower in accordance with their
respective terms, except as limited by any applicable Debtor Relief Laws, (d)
the execution, delivery and performance by Borrower of this Amendment and any
Credit Documents to be delivered under this Amendment do not require the consent
of any other Person and do not and will not constitute a violation of any
Governmental Requirements, agreements or understandings to which Borrower is a
party or by which Borrower is bound, (e) the representations and warranties
contained in the Credit Agreement, as amended by this Amendment, and any other
Credit Document are true and correct in all material respects as of the date of
this Amendment, and (f) as of the date of this Amendment, no Event of Default or
Potential Default exists or is imminent.

6. References. All references in the Credit Documents to the "Credit Agreement"
refer to the Credit Agreement as amended by this Amendment. This Amendment is a
"Credit Document" referred to in the Credit Agreement and the provisions
relating to Credit Documents in the Credit Agreement are incorporated by
reference, the same as if set forth verbatim in this Amendment.

7. Counterparts. This Amendment may be executed in any number of counterparts
with the same effect as if all signatories had signed the same document.


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8. Parties Bound. This Amendment binds and inures to the benefit of Borrower,
Administrative Agent and each Lender, and, subject to Section 13 of the Credit
Agreement, their respective successors and assigns.

9. Entirety. THIS AMENDMENT, THE CREDIT AGREEMENT AS AMENDED BY THIS AMENDMENT,
AND THE OTHER CREDIT DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES
FOR THE TRANSACTIONS THEREIN, AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENT BETWEEN THE PARTIES. THERE ARE NO
UNWRITTEN ORAL AGREEMENT BETWEEN THE PARTIES.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK.
                            SIGNATURE PAGE FOLLOWS.]


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         EXECUTED as of the date first stated above.

                                     BANK ONE, NA,
                                     as Administrative Agent and a Lender


                                     By:
                                        ----------------------------------------
                                           Bradley C. Peters,  Vice President



                                     PMC CAPITAL, INC.,
                                     as Borrower


                                     By:
                                        ----------------------------------------
                                     Name:
                                          --------------------------------------
                                     Title:
                                           -------------------------------------


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