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                                                                    EXHIBIT 10.5



                               AMENDMENT NO. ONE
                            TO MANAGEMENT AGREEMENT

         THIS AMENDMENT NO. ONE dated this 1st day of January, 1996, is made by
and between Intelect Systems Corp., a Delaware corporation (the "(Company") and
Herman Frietsch (the "Manager"), and is entered into to amend, as set forth
herein, the terms and provisions of that certain Management Agreement dated
October 1, 1995 by and between the Company and Manager.

         For and in consideration of the mutual covenants and agreements set
forth herein, the Company and Manager hereby amend the Management Agreement as
set forth herein:

         1.      Term. Section II of the Management Agreement is hereby amended
to be and read as follows:

         II.     TERM. Subject to the provisions for termination as hereinafter
                 provided, the term of this Agreement, as amended from time to
                 time, shall be for an initial term from October 1, 1995 to
                 December 31, 1997.  Thereafter, the term shall be continuous,
                 provided, however, that this Agreement may be terminated by
                 Manager or the Company in the following manner: if either
                 party so desires to terminate this Agreement, it shall provide
                 written notice to the other party, and the effective date of
                 such termination shall be on the next December 31 following
                 three (3) years from the other party's receipt of such notice
                 of termination. For example, if a party sends notice of
                 termination and it is received by the other party on July 1,
                 1998, then the effective date of termination shall be December
                 31, 2001.

         2.      Position. Section III of the Management Agreement is hereby
amended to be and read as follows:

         III.    POSITION. Manager has extensive experience in general
                 management direction and oversight, strategic planning,
                 mergers, ventures, acquisitions and divestitures which is
                 deemed beneficial to the Company and which the Company wishes
                 to apply to its activities and plans. Manager will hold the
                 executive position of Executive Chairman of the Board of
                 Directors of the Company and will be the Company's designee
                 for similar or related positions on the boards of directors of
                 the Company's subsidiaries and affiliates, which may also
                 provide for compensation for such additional responsibilities
                 and obligations. Manager will be responsible for advising and
                 making recommendations to the Board of Directors with respect
                 to the best interest of the Company. He will operate within
                 the Company's bylaws, goals, guidelines, budgets, directives,
                 policies and procedures.

         3.      Compensation. The first sentence of Section IV is hereby
amended to be and read as follows:
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         IV.     COMPENSATION. Manager's basic compensation ("Basic
                 Compensation") shall be $250,000 for each yearly period of the
                 Term of this Agreement payable in equal monthly installments
                 on the last day of each month or as otherwise agreed upon
                 between the parties.

         4.      Miscellaneous. A new Section XIV shall be added, and such
Section XIV as added shall be and read as follows:

         XIV.    MISCELLANEOUS. It is expressly agreed between the Company and
                 Manager that with respect to any options granted by the
                 Company or its parent corporation, Intelect Communications
                 Systems Limited ("Intelect") to the Manager which are
                 outstanding as of the effective date of termination of this
                 Agreement. the expiration date of such options shall be the
                 effective date of termination of this Agreement. In addition,
                 in the event the Company terminates Manager's employment
                 pursuant to the second sentence of Section X of this
                 Agreement, all unvested options issued and outstanding to
                 Manager as of the date of such termination shall vest upon
                 such termination. The parties agree that all currently issued
                 and outstanding options and all options to be granted in the
                 future to Manager shall reflect the agreements set forth in
                 this Section XIV.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first above written.


                                        "COMPANY"

                                        INTELECT SYSTEMS CORP.

                                        /s/ PETER G. LEIGHTON
                                        ----------------------------------------
                                        Peter G. Leighton, President


                                        "MANAGER"

                                        /s/ HERMAN M. FRIETSCH
                                        ----------------------------------------
                                        Herman M. Frietsch