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                                                                    EXHIBIT 99.5


                                 FIRST AMENDMENT
                                       TO
                           CONVERTIBLE PROMISSORY NOTE

         THIS FIRST AMENDMENT TO CONVERTIBLE PROMISSORY NOTE (the "Amendment")
is made and entered into as of December 29, 2000, by and between CYBERGUARD
CORPORATION, a Florida corporation ("Maker"), and FERNWOOD PARTNERS II, LLC, a
Delaware limited liability company ("Payee").

         RECITALS:

         A. Maker executed and delivered on August 26, 1999, a certain
Convertible Promissory Note (the "Note") in the principal amount of Three
Million Six Hundred Ninety Nine Thousand Four Hundred Eighty Four and 38/100
Dollars ($3,699,484.38), payable to Payee.

         B. The parties desire to amend the Note in certain respects as set
forth herein.

         AGREEMENT:

         NOW, THEREFORE, for and in consideration of these premises, the mutual
promises set forth herein, and other good and valuable consideration, the
receipt and adequacy of which are hereby acknowledged, the parties hereby agree
as follows:

        1. DEFINED TERMS. Capitalized terms not otherwise defined in this
Amendment shall have the meanings ascribed to such terms in the Note.

        2. INTEREST. The following sentence shall be added to the end of
Section 1:

         "All interest on this Note shall be compounded quarterly on January 1,
         April 1, July 1 and October 1 of each year commencing on October 1,
         1999."

Notwithstanding the foregoing, the parties acknowledge and agree that the
interest payment made by Maker to Payee on October 1, 2000, in the amount of
$117,020.73 shall not be compounded.

         3. PRINCIPAL AND INTEREST PAYMENTS. Section 2 of the Note shall be
deleted in its entirety and replaced with the following:

                  "2. Principal and Interest Payments. Notwithstanding anything
         contained herein to the contrary, all principal due hereunder together
         with all accrued interest shall become immediately due and payable
         without further notice on June 30, 2002.


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         In the event that any payment date shall fall due on a Saturday,
         Sunday, legal holiday or a day on which federal banking institutions
         are not required to be open, payment shall be made on the next business
         day, but interest, shall continue to accrue until such payment is
         made."

         4. EFFECT OF AMENDMENT; GENERAL PROVISIONS. Except as set forth in this
Amendment, the terms and provisions of the Note are hereby ratified and declared
to be in full force and effect. This Amendment shall become effective upon its
execution, which may occur in one or more counterparts, each of which shall be
deemed an original, but all of which together shall constitute one and the same
instrument. Captions and paragraph headings are used herein for convenience
only, are not a part of this Amendment or the Note as amended by this Amendment
and shall not be used in construing either document. Other than the reference to
the Note contained in the first paragraph of this Amendment, each reference to
the Note and any agreement contemplated thereby or executed in connection
therewith, whether or not accompanied by reference to this Amendment, shall be
deemed a reference to the Note as amended by this Amendment.

                                                          SIGNATURE PAGE FOLLOWS


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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed in multiple originals by their authorized officers, all as of the day
and year first above written.


                                    CYBERGUARD CORPORATION



                                    By: /s/ Terrence A. Zielinski
                                        ----------------------------------------
                                    Title: Chief Financial Officer
                                           -------------------------------------
                                                       ("maker")


                                    FERNWOOD PARTNERS II, LLC

                                    By: Richard L. Scott Revocable Trust, Member



                                    By: /s/ Richard L. Scott
                                        ----------------------------------------
                                    Title: Trustee
                                           -------------------------------------
                                                        ("Payee")