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                                                                   Exhibit 10.20



             AMENDMENT NO. 2 TO CONVERTIBLE SECURED PROMISSORY NOTE


         This AMENDMENT NO. 2 TO CONVERTIBLE SECURED PROMISSORY NOTE (this
"Amendment"), effective as of June 1, 2000, is executed by MigraTEC, Inc., a
Florida corporation (the "Company"), in favor of Mercury Fund No. 1, Ltd., a
Texas limited partnership ("Mercury").

                                    RECITALS:

         WHEREAS, the Company executed and delivered to Mercury that certain
Convertible Secured Promissory Note, dated January 25, 2000, as amended, in the
principal sum of up to $1,775,000 (the "Note"); and

         WHEREAS, the Company desires to further amend the Note in certain
respects as herein provided;

         NOW, THEREFORE, in consideration of the foregoing and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, and subject to the conditions set forth herein, the parties hereto
agree as follows:

         SECTION 1. AMENDMENT OF AUTOMATIC CONVERSION PROVISION.

         (a)      The following paragraph contained in the Note is hereby
                  deleted and removed from the Note:

                           "This Note shall automatically convert (an 'Automatic
                  Conversion'), if not sooner converted at the election of the
                  holder as provided herein, into shares of the Company's Series
                  A Preferred Stock at such time as the Company has obtained the
                  approval of its shareholders to the creation of the Series A
                  Preferred Stock and has filed with the Secretary of State of
                  Florida (a) Articles of Amendment to its Articles of
                  Incorporation authorizing the creation of the Series A
                  Preferred Stock and (b) a resolution of the Board of Directors
                  of the Company containing a Statement of Designations, Rights,
                  Preferences and Privileges of the Series A Preferred Stock of
                  the Company, setting forth the terms of the Series A Preferred
                  Stock, provided, that the Company has used its best efforts to
                  take such actions as soon as practical and in any event by
                  June 30, 2000. In connection with an Automatic Conversion of
                  this Note, the amount of this Note shall convert into the
                  number of fully paid and non-assessable shares of Series A
                  Preferred Stock of the Company as determined by dividing (x)
                  the then outstanding amount of this Note by (y) $0.125 (the
                  'Conversion Price')."

         (b)      The following paragraph shall replace in the Note the deleted
                  paragraph from the Note set forth in Section 1(a) of this
                  Amendment:



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                           "Subject to Section 2.9 of the Purchase Agreement,
                  this Note shall automatically convert (an 'Automatic
                  Conversion'), if not sooner converted at the election of the
                  Payee as provided herein, into shares of the Company's Common
                  Stock effective upon the earlier of either (i) the closing of
                  a bona fide sale of shares of its capital stock, including,
                  but not limited to, common stock or preferred stock, or the
                  issuance of debt securities with equity features, in one or
                  more transactions in which the Company receives aggregate
                  proceeds of at least $5,000,000, or (ii) the first trading day
                  for the OTC Bulletin Board (or such exchange on which the
                  Company's Common Stock is listed for trading) following a
                  period of ninety (90) consecutive trading days during which
                  the closing sale price per share of the Company's Common Stock
                  has been in excess of $1.25, such 90-day period to begin at
                  any time after June 1, 2000; provided, however, that the
                  automatic conversion of this Note into shares of Common Stock
                  pursuant to this paragraph shall not be effective prior to the
                  effective date of the Shelf Registration (as defined in the
                  Registration Rights Agreement)." In connection with an
                  Automatic Conversion of this Note, the amount of this Note
                  shall convert into the number of fully paid and non-assessable
                  shares of the Company's Common Stock as determined by dividing
                  (x) the then outstanding amount of this Note by (y) $0.125
                  (the 'Conversion Price')."

         SECTION 2. OTHER PROVISIONS UNAFFECTED. Except as specifically modified
by this Amendment, all terms and conditions contained in the Note shall continue
in full force and effect. Capitalized terms not otherwise defined herein shall
have the meanings given to them in the Note.



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             AMENDMENT NO. 2 TO CONVERTIBLE SECURED PROMISSORY NOTE

                                 Signature Page

         IN WITNESS WHEREOF, the undersigned have caused this Amendment to be
executed effective as of the date first written above.

                                    COMPANY:

                                    MIGRATEC, INC.


                                    By:   /s/ Curtis Overstreet
                                          --------------------------------
                                          Curtis Overstreet
                                          President


                                    AGREED TO AND ACCEPTED:

                                    MERCURY FUND NO. 1, LTD.

                                    By:   MERCURY VENTURES, LTD.
                                          General Partner


                                    By:   MERCURY MANAGEMENT, L.L.C.
                                          General Partner

                                          By:  /s/ Kevin Howe
                                             -----------------------------
                                               Kevin Howe, Manager