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                                                                   Exhibit 10.24


                     FIRST AMENDMENT TO EMPLOYMENT AGREEMENT

         This First Amendment to Employment Agreement (this "Amendment"), dated
and effective as of the 15th day of September, 1998, is by and between
HighwayMaster Corporation, a Delaware corporation ("Employer"), and Jana A.
Bell, an individual residing in Dallas County, Texas ("Employee").

                                    RECITALS

         Employer and Employee entered into that certain Employment Agreement,
dated and effective as of the 29th day of May, 1998 (the "Employment
Agreement"), and the parties wish to amend the Employment Agreement to reflect a
change in the title of Employee, such change having been approved by the Board
of Directors of Employer at a meeting of the Board of Directors held on even
date herewith.

         NOW, THEREFORE, in consideration of the foregoing and of the mutual
covenants set forth herein and in the Employment Agreement, Employer and
Employee, intending to be legally bound, hereby agree as follows:

         1.      Change of Title. Every occurrence of the title "Chief Financial
Officer" as it occurs in the Employment Agreement shall be deleted and replaced
with the term "President and Chief Executive Officer".

         1.       Change of Salary. The first sentence of Section 3(a) of the
                  Employment Agreement shall be replaced with the following:

         a.       Salary. Employee shall receive a salary of $25,000 per month
                  payable by Employer in bi-monthly amounts in Dallas, Texas.

         2.       Change of Bonus. The third sentence of Section 3(c) of the
                  Employment Agreement shall be replaced by the following two
                  sentences:

                  The potential annual bonus which may be awarded to Employee
                  shall be in the amount of $50,000 at the first fiscal year end
                  of Employer after execution of this Agreement, and 50% of
                  actual base salary paid to Employee pursuant to Section 3(a)
                  above in subsequent fiscal years. The $50,000 bonus for which
                  Employee is eligible for the first fiscal year end of Employer
                  shall be paid early, such that the $50,000 shall be deemed
                  earned and payable to Employee on September 15, 1998.

         3.       Vesting on Change of Control. The following sentence shall be
inserted immediately prior to the last sentence in Section 4 of the Employment
Agreement:

                  In addition, the options granted as of August 12, 1998 and
                  September 18, 1998 



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                  will accelerate and will vest immediately upon a Change in
                  Control of Employer.

         4.       Incorporation of Amendment. This Amendment shall be included
with and incorporated into the Employment Agreement for all purposes, provided
that no effective date or other time period set forth in the Employment
Agreement shall be amended or affected by the effective date of this Amendment.
The terms set forth in the Employment Agreement shall govern interpretation and
enforcement of this Amendment.

         IN WITNESS WHEREOF, the parties have executed this Amendment as of the
date first above written.


                                 EMPLOYER:
                                 HIGHWAYMASTER CORPORATION


                                 By: /S/ J. RAYMOND BILBAO      2/22/99
                                     ------------------------------------------
                                     J. Raymond Bilbao
                                     Secretary and General Counsel

                                 EMPLOYEE:


                                    /S/ JANA A. BELL            2/1/99
                                 ----------------------------------------------
                                 JANA A. BELL