<PAGE>

                                                                   EXHIBIT 10.31

                          AGREEMENT AND MUTUAL RELEASE


         THIS AGREEMENT AND MUTUAL RELEASE ("Agreement"), effective on the date
hereof, is entered into in Richardson, Texas by and between Minorplanet Systems
USA, Inc., formerly known as @Track Communications, Inc., a Delaware
corporation, with its principal place of business located at 1155 Kas Drive,
Suite 100, Richardson, Texas, 75081 ("Employer"), and Jana A. Bell, an
individual residing 305 Falcon Court, Coppell, Texas, 75019 ("Executive").

         WHEREAS, on June 21, 2001, Jana A. Bell and @Track Communications,
Inc., now known as Minorplanet Systems USA, Inc. ("MPUSA") entered into that
certain Employment Agreement ("Employment Agreement") which Employment Agreement
is incorporated herein as if fully set forth at this point;

         WHEREAS, on June 21, 2002, the initial one (1) year term of the
Employment Agreement expired and the Employment Agreement continued in effect on
a month to month basis;

         WHEREAS, throughout the month of July 2002, Employer and Executive
engaged in negotiations regarding Executive's continued employment with Employer
under the Employment Agreement;

         WHEREAS, Employer and Executive were unable to reach agreement on the
terms and conditions of Executive's continued employment with Employer; and

         WHEREAS, Executive and Employer agreed to a termination of their
employment relationship on those terms as set forth below.

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

1)   Employer shall provide Executive with the compensation as set forth in
     Paragraph 6(a), (b), (c) and (d) of the Employment Agreement, including the
     following:

     a)   Severance pay equal to seven (7) months base salary under the
          Employment Agreement in the total amount of $175,000.00. MPUSA shall
          pay such sum according to the following payment schedule:

                    (i)  $87,500, less $41,500 in federal withholding tax, less
                         applicable deductions for social security and Medicare,
                         to be paid contemporaneously with the execution of this
                         Agreement;

                    (ii) $29,166.66, less $13,833.33 in federal withholding tax,
                         less applicable deductions for social security and
                         Medicare on or before October 15, 2002;


                    (iii) $29,166.66, less $13,833.33 in federal withholding
                         tax, less applicable deductions for social security and
                         Medicare on or before November 15, 2002; and,

                    (iv) $29,166.66, less $13,833.33 in federal withholding tax,
                         less applicable deductions for social security and
                         Medicare on or before December 15, 2002.

     b)   Any salary earned by Executive prior to August 23, 2002 as provided in
          Paragraph 3(a) of the Employment Agreement;

     c)   any accrued, but unpaid, vacation benefits;

     d)   any authorized but unreimbursed business expenses; and

     e)   continued medical insurance benefits, at Employer's expense, for a
          period of twelve (12) months from the date of separation.


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                                  EXHIBIT 10.31
                          AGREEMENT AND MUTUAL RELEASE


2)   The parties acknowledge that pursuant to Section 3(c) of the Employment
     Agreement, an annual discretionary bonus may be awarded in whole or in part
     based on the level of incentive bonus plan performance criteria achieved by
     Executive, in the sole judgment of the Board of Directors of Employer.
     MPUSA represents that as of the date of this Agreement the Compensation
     Committee of the Board of Directors ("Committee") has determined, in its
     sole discretion, that no bonuses shall be awarded to Employer's senior
     executive team, including Employee, for the fiscal year ending August 31,
     2002. Accordingly, as of the date of this Agreement, Executive shall not
     receive a bonus for the fiscal year ending August 31, 2002. In the event
     the Committee and/or the Board of Directors reverses this decision, and any
     member of the senior executive team is awarded a bonus for the fiscal year
     ending August 31, 2002, then Executive shall receive an award equal to the
     average percentage of targeted goals achieved by the other members of the
     senior executive team; however, such bonus, if any, shall be no less than
     fifty percent (50%) of the maximum annual bonus set forth in paragraph 3(c)
     of the Employment Agreement.

3)   Executive shall resign her position as a Director on the Board of Directors
     of Employer, Minorplanet Systems USA Ltd. and Caren (292) Ltd. effective
     August 23, 2002.

4)   RELEASE OF MPUSA. Executive agrees on behalf of herself and all of her
     heirs or personal representatives, to release MPUSA, all of MPUSA's
     affiliates, including parent companies and subsidiaries, and all of MPUSA's
     present and former officers, directors, agents, employees, employee benefit
     programs, and the trustees, administrators, fiduciaries, and insurers of
     such programs, from any and all claims for relief of any kind, whether
     known to her or unknown, which in any way arise out of or relate to her
     employment, the termination of her employment with MPUSA, the Employment
     Agreement, and concerning events occurring at any time up to the date of
     this Agreement including, but not limited to, any and all claims of
     discrimination of any kind and any and all contractual, tort or other
     common law claims, whether legal or equitable, including under any
     applicable federal laws, including, but not limited to Title VII of the
     Civil Rights Act of 1964, the Civil Rights Act of 1991, 42 U.S.C. Section
     1981, the American with Disabilities Act, the Equal Pay Act, the Worker
     Adjustment and Restraining Notification Act, the Employment Retirement
     Income Security Act, the Family Medical Leave Act, or under any applicable
     state or local laws or ordinances or any other legal restrictions on
     MPUSA's rights, including the Texas Commission on Human Rights Act.
     However, the releases set forth herein do not include the release of any
     claims arising under this Agreement, any rights Executive may have for
     pension or retirement benefits, any rights for COBRA benefits, any rights
     Executive may have as a shareholder of MPUSA, and any rights Executive has
     in stock options granted to the Executive during the term of employment.

5)   RELEASE AND INDEMNIFICATION OF EXECUTIVE. MPUSA, all of its affiliates,
     including parent companies and subsidiaries, hereby releases Executive from
     any and all claims for relief of any kind, whether known or unknown, which
     in any way arise out of or relate to Executive's employment with MPUSA.
     MPUSA shall continue to indemnify Executive to the fullest extent permitted
     by law, and as set forth in the Bylaws of MPUSA, against all judgments,
     penalties, fines, settlements and reasonable expenses actually incurred by
     Executive in connection with any proceeding in which Executive is, or
     threatened to be named, a defendant because of Executive's position as a
     director, officer, employee or agent of MPUSA.

6)   Neither MPUSA nor Executive shall disparage the character, reputation, or
     business of the other in communications with any other person or entity.

7)   Executive further agrees to adhere to all terms and conditions of the
     Employment Agreement which survive termination thereof, including but not
     limited to, Section 4 thereof. Further, the parties agree not to disclose
     or misrepresent to anyone the terms of this Agreement, except as may be
     required by law.


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                                  EXHIBIT 10.31
                          AGREEMENT AND MUTUAL RELEASE


8)   This Agreement does not constitute an admission of any kind by either
     party. The parties understand and agree that if either party violates this
     Agreement, the injured party may sue the offending party for the damages
     caused by such breach and/or for injunctive relief to enforce this
     Agreement.

9)   This Agreement shall be governed by and construed in accordance with the
     laws of the state of Texas, without giving effect to the conflict of laws
     (rules) or choice of laws (rules) thereof. The parties consent to the
     exclusive personal jurisdiction and venue of the state district court
     residing in Dallas County, Dallas, Texas (or if applicable, the federal
     district court for the Northern District of Texas, Dallas Division) for all
     litigation which may be brought with respect to or arising out of the terms
     of and the transactions and relationships contemplated by this Agreement.


10)  Executive acknowledges and agrees that Executive is entering into this
     Agreement freely and voluntarily and Executive is satisfied that Executive
     has been given sufficient opportunity to consider it and consult with an
     attorney. Executive acknowledges that Executive has carefully read and
     understands all of the provisions of this Agreement.

11)  Executive represents that no other statements, promises, or commitments of
     any kind, written or oral, have been made to Executive by MPUSA, or any of
     its agents, to cause Executive to accept it. Executive acknowledges that
     Executive has been advised to consult legal counsel concerning this
     Agreement prior to signing the Agreement, and that Executive have been
     given sufficient opportunity to do so. Executive acknowledges acceptance of
     this Agreement by her signature below:


     IT IS SO AGREED, on the 24 day of September, 2002.


       /s/ Jana Ahlfinger Bell           MINORPLANET SYSTEMS USA, INC.
       -----------------------
           Jana A. Bell
                                         By: /s/ J. Raymond Bilbao
                                            ---------------------------
                                         Its: Sr. V.P., General Counsel
                                              & Secretary


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