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                                                                   EXHIBIT 10.23

                             WEBLINK WIRELESS, INC.

                       AMENDED KEY EMPLOYEE RETENTION PLAN

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                             WEBLINK WIRELESS, INC.

                       AMENDED KEY EMPLOYEE RETENTION PLAN

                                TABLE OF CONTENTS

<Table>
<S>                                                                          <C>
SECTION 1

         General
         1.1      History and Purpose                                        4
         1.2      Plan Amount                                                4
         1.3      Plan Administration                                        4
         1.4      Action by the Company                                      4

SECTION 2

         Participation
         2.1      Participation                                              5
         2.2      Participation Agreement                                    5
         2.3      Nonparticipation                                           5

SECTION 3

         Retention Event and Change in Control
         3.1      Retention Event                                            5

SECTION 4

         Retention Bonus
         4.1      Retention Bonus                                            6
         4.2      Participant's Base Amount                                  6
         4.3      Deemed Retention Event                                     6
         4.4      Cause                                                      7
         4.5      Disability                                                 7
         4.6      Termination for Good Reason                                7

SECTION 5

         Confidentiality and Non-Competition
         5.1      Confidentiality and Non-Competition - General              7
         5.2      Confidential Information                                   8
</Table>

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<Table>
<S>                                                                          <C>
         5.3      Non-Competition                                            9

SECTION 6

         Enforcement
         6.1      Arbitration of Disputes                                    9
         6.2      Reimbursement of Costs and Expenses                        9

SECTION 7

         Amendment of Termination
         7.1      Amendments and Terminations                                10
         7.2      Participant Rights                                         10
         7.3      Successors                                                 10

SECTION 8

         Miscellaneous
         8.1      Mitigation and Set-Off                                     10
         8.2      Non-Alienation                                             10
         8.3      Withholding                                                11
         8.4      Source of Payments                                         11
         8.5      Notices                                                    11
         8.6      Gender and Number                                          11
         8.7      No Rights to Employment or Continuation of Relationship    11
         8.8      Governing Law                                              11
         8.9      Severability                                               11
         8.10     No Limitation Upon the Rights of the Company               12
         8.11     No Liability for Good Faith Determinations                 12
</Table>

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                             WEBLINK WIRELESS, INC.
                       AMENDED KEY EMPLOYEE RETENTION PLAN

                                    SECTION 1

                                     GENERAL

     1.1 HISTORY AND PURPOSE. The Board of Directors (the "Board") of WebLink
Wireless, Inc., a Delaware corporation (the "Company"), believes that the
prospect of a pending Retention Event inevitably creates distractions and
personal risks and uncertainties for a company's key employees. The Board
further believes that, because certain key employees' continued performance of
their job functions and duties is critical to the success of the Company, it is
in the best interests of the Company to minimize such distractions and to
encourage its key employees' full attention and dedication to their duties.
Accordingly, this WebLink Wireless, Inc. Amended Key Employee Retention Plan
(the "Amended Plan") is established by the Company to promote the long-term
financial interests of the Company by providing the key employees of the Company
with an incentive to remain employed with the Company so they can continue to
actively perform their job functions and duties with full attention and
dedication while a Retention Event is pending. This Amended Plan supersedes and
voids any and all previous oral and written retention and severance plans and
agreements in effect for Participants, including the previous Key Employee
Retention Plan which went into effect on February 14, 2001 (the "Previous
Plan"). Notwithstanding the foregoing, the Company's standard severance practice
and/or policy (as published by the Company at the time a Participant is
terminated without Cause) (the "Standard Severance Policy") shall remain in full
force and effect.

     1.2 PLAN AMOUNT. The total distributions under the Amended Plan shall not
exceed the sum of $2,500,000. Under no circumstances, shall the funds available
for distribution under the Amended Plan exceed $2,500,000, including the amounts
proposed to be paid by the Company pursuant to the Pre-Petition Retention Bonus
Program.

     1.3 PLAN ADMINISTRATION. The authority to control and manage the operation
and administration of the Amended Plan shall be vested in the Board.

     1.4 ACTION BY COMPANY. Any action required or permitted to be taken by the
Company under the Amended Plan shall be by resolution of its Board of Directors.

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                                    SECTION 2

                          ELIGIBILITY AND PARTICIPATION

     2.1 ELIGIBILITY AND PARTICIPATION. In order to be eligible to be a
Participant in this Amended Plan an employee must:

     (1)  Be a full time regular employee of the Company (as that classification
          is used in the normal business practices of the Company); and

     (2)  Have been designated as a Participant and have had a Retention
          Percentage established by the Company's Board of Directors, and

     (3)  Voluntarily sign a Release of Claims in form and substance reasonably
          acceptable to the Company.

     2.2 PARTICIPATION AGREEMENT. The participation of each Participant shall be
evidenced by a Participation Agreement in substantially the form attached hereto
as Exhibit A.

     2.3 NONPARTICIPATION. Notwithstanding any provisions in the Amended Plan,
John Beletic has agreed not to participate as a Participant under the Amended
Plan.

                                    SECTION 3

                      RETENTION EVENT AND CHANGE IN CONTROL

     3.1 RETENTION EVENT. For purposes of the Amended Plan, the term "Retention
Event" means the first to occur of the following:

     (1)  the date upon which a Plan of Reorganization is confirmed by the court
          in the Company's Chapter 11 bankruptcy proceeding (the "Court").

     (2)  there is consummated an agreement for the sale, lease or other
          disposition by the Company of all or substantially all of the
          Company's assets in which the proceeds to the Company from such sale,
          lease or disposition are sufficient to pay all claims against the
          Company having a higher priority of payment than Participants' claims
          under this Amended Plan.

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                                    SECTION 4

                                 RETENTION BONUS

     4.1 RETENTION BONUS. Subject to the provisions of this Amended Plan, a
Participant shall be entitled to receive a Retention Bonus (as defined in this
Section) if the Participant remains continuously employed with the Company (or
its successor in interest) from the date he or she is designated a Participant
by the Board through the date a Retention Event occurs (the "Retention Trigger
Date"). As used herein, "Retention Bonus" shall mean Participant's Retention
Percentage as shown in his/her Participation Agreement times the Participant's
Base Amount (as defined in Section 4.2). Except as set forth in Section 4.3
herein, the Retention Bonus shall be paid in equal monthly installments over 12
months beginning on the fifth business day after the Retention Trigger Date. In
the event that Participant's employment is terminated after the Retention
Trigger Date by the Company without Cause (as defined in Section 4.4) or by the
Participant for Good Reason (as defined in Section 4.6), he/she will be entitled
to continue receiving monthly Retention Bonus payments until the Retention Bonus
is fully paid. If Participant's employment is terminated for any other reason,
he/she will not be entitled to receive any further Retention Bonus payments.

     4.2 PARTICIPANT'S BASE AMOUNT. Subject to the limitations set forth in
Section 1.2 of the Amended Plan, the Participant's Base Amount is equal to the
sum of:

     (1)  the Participant's annual rate of salary or base compensation as set
          forth in the Participant's Participation Agreement; plus

     (2)  the Participant's target bonus percentage rate (including annual and
          MBO bonus programs) set forth in his/her Participation Agreement times
          the amount described in clause (1) of this Section.


     4.3 DEEMED RETENTION EVENT. If the Participant's employment is terminated
by the Company before the Retention Trigger Date and such termination is by the
Company for a reason other than Cause (as defined in Section 4.4), death or
Disability (as defined in Section 4.5) or is by the Participant because of Good
Reason (as defined in Section 4.6), then as to such Participant only, a
Retention Event shall be deemed to have occurred immediately prior to such
termination. When such a deemed Retention Event occurs, Participant shall be
entitled to the greater of (i) one-half of the Retention Bonus (as defined in
Section 4.1), paid in lump sum within 10 days after Participant's termination,
or (ii) any severance amounts due to Participant in accordance with the
Company's then Standard Severance Policy (the "Severance Amount"). Upon the
occurrence of a termination event, Participant will not be entitled to more than
either his/her Retention Bonus or Severance Amount (whichever the Participant
elects).

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     4.4 CAUSE. For purposes of this Amended Plan, the term "Cause" means (i) a
Participant willfully engaging in conduct materially injurious to the Company,
or (ii) the willful and continual failure by a Participant to substantially
perform the duties assigned to the Participant (other than any failure resulting
from the Participant's incapacity due to physical injury or illness or mental
illness), which failure has not been corrected by the Participant within 30 days
after receipt of a written notice from the Chief Executive Officer or Board of
Directors of the Company specifying the manner in which the Participant has
failed to perform such duties, or (iii) a Participant's violation of the written
policies of the Company that, in accordance with the normal employment practices
of the Company, has become a termination event. No act, or failure to act, by a
Participant shall be deemed "willful" unless done, or omitted to be done, not in
good faith and without reasonable belief that such action or omission was in the
best interest of the Company.

     4.5 DISABILITY. For purposes of this Amended Plan, the term "Disability"
shall have the meaning set forth under the Company's long-term disability plan
or policy.

     4.6 TERMINATION FOR GOOD REASON. For purposes of this Amended Plan, a
termination because of "Good Reason" means a resignation by a Participant
following the occurrence of:

     (1)  a reduction of 25% or more in the Participant's annual base salary
          without the consent of the Participant;

     (2)  the Company's failure to perform or observe any of the material terms
          of this Amended Plan.

                                    SECTION 5

                       CONFIDENTIALITY AND NON-COMPETITION

     5.1 CONFIDENTIALITY AND NON-COMPETITION - GENERAL. Any benefits payable
under this Amended Plan are conditioned upon and subject to the terms of this
Section 5. To the extent that a Participant violates any provision of this
Section 5, the Company will have no further obligation to provide any benefit or
payment due hereunder, and will also have any other remedies available to the
Company for such violation including but not limited to a preliminary
injunction, temporary restraining order or other equivalent relief. Section 5 is
in addition to the confidentiality and non-competition agreements signed at or
during employment with the Company. The Participant's receipt of payments under
this Amended Plan constitutes the Participant's ratification and reaffirmation
of such prior agreements as well as those in this Amended Plan.

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     5.2 CONFIDENTIAL INFORMATION. The Participant agrees that:

     (1)  Except as may be required by law, by lawful judicial, governmental or
          regulatory authority, or by lawful order of a court or agency of
          competent jurisdiction, or except to the extent required to perform
          the Participant's duties during the course of his/her employment with
          the Company or to the extent that the Participant has express written
          authorization from the Company, the Participant (i) shall keep secret
          and confidential all Confidential Information (as defined below), (ii)
          shall not disclose the same, either directly or indirectly, to any
          other person, and (iii) shall not use it in any way.

     (2)  For purposes of this Amended Plan, the term "Confidential Information"
          means all non-public information concerning the Company and its
          affiliates that was acquired by or disclosed to the Participant during
          the course of employment with the Company, or during the course of
          consultation with the Company following the Participant's date of
          termination, including, without limitation:

          (i)  any non-public information regarding the Company's and its
               affiliates' customers, services, processes, costs, operations and
               methods, whether past, current or planned, as well as knowledge
               and data relating to business plans, marketing and sales
               information originated, owned, controlled or possessed by the
               Company or its affiliates; and

          (ii) information regarding litigation and pending litigation involving
               or affecting the Company or its affiliates.

     (3)  To the extent that the Participant obtains information on behalf of
          the Company or any of its affiliates that may be subject to
          attorney-client privilege as to the Company's or its affiliates'
          attorneys, the Participant shall take reasonable steps to maintain the
          confidentiality of such information and to preserve such privilege.

     (4)  The Participant agrees that effective with the date of termination,
          the Participant will deliver to the Company all papers, books,
          manuals, lists, correspondence, documents, computer programs, computer
          spreadsheets, data captured on machine-readable media, and other
          material containing or relating to the Confidential Information,
          together with all copies thereof, that are in the Participant's
          possession or control, other than such materials as shall be necessary
          to permit the Participant to prepare the Participant's tax returns.

     (5)  Nothing in this Section 5.2 shall be construed so as to prevent the
          Participant from using, in connection with his employment for himself
          or an

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          employer other than the Company or any of its affiliates, knowledge
          that was acquired by Participant during the course of his employment
          with the Company and its affiliates, and which is generally known to
          persons of his experience in other companies in the same industry.

     5.3 NONCOMPETITION. Each Participant who holds the position of Director or
higher as of the Effective Date of this Amended Plan, and who becomes eligible
for a Retention Bonus under Section 4, agrees as further consideration for such
benefit that, for a period of 6 months after the date of termination, the
Participant shall not be employed by, or otherwise engage or be interested in,
any business which is competitive with any business of the Company or of any of
its subsidiaries in which the Participant was engaged during his employment
prior to his termination, but this restriction shall apply only if such
employment or activity is likely to cause, or causes, serious damage to the
Company or any of its subsidiaries.

                                    SECTION 6

                                   ENFORCEMENT

     6.1 ARBITRATION OF DISPUTES. All claims arising out of or relating to this
Amended Plan shall be settled by arbitration in the city in which the principal
executive offices of the Participant's Company are located (disregarding any
transfer of such offices after a Retention Event), by three arbitrators, one of
whom shall be appointed by the Company, one by the Participant and the third of
whom shall be appointed by the first two arbitrators. If the first two
arbitrators cannot agree on the appointment of a third arbitrator, then the
third arbitrator shall be appointed by the Chief Judge of the United States
District Court for such location. Each party shall pay the fees and expenses of
the arbitrator appointed by it and one-half of the fees and expenses of the
third arbitrator. The arbitration shall be conducted in accordance with the
rules of the American Arbitration Association, except with respect to the
selection of arbitrators which shall be as provided in this Section. The
decision of the arbitrators shall be final and binding and judgment upon the
award rendered by the arbitrators may be entered in any court having
jurisdiction thereof.

     6.2 REIMBURSEMENT OF COSTS AND EXPENSES. In the event that it shall be
necessary or desirable for a Participant to retain legal counsel or incur other
costs and expenses in connection with enforcement of rights under the Amended
Plan, the Company shall pay (or the Participant shall be entitled to recover
from the Company, as the case may be) reasonable attorneys' fees and costs and
expenses in connection with enforcement of such rights (including the
enforcement of any arbitration award in court) to the extent determined by the
arbitrators.

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                                    SECTION 7

                            AMENDMENT OR TERMINATION

     7.1 AMENDMENT AND TERMINATION. Subject to the provisions of Section 7.2:

     (1)  The Company's Senior Vice President - Human Resources, or such other
          officer of the Company as may from time to time be primarily
          responsible for human resource matters, may, with the concurrence of
          the Company's Senior Vice President and General Counsel and Chief
          Executive Officer, make minor or administrative written amendments to
          the Amended Plan;

     (2)  the Board of Directors of the Company may not terminate or amend the
          Amended Plan without the prior approval of the bankruptcy court.

     7.2 PARTICIPANT RIGHTS. No amendment or termination of the Amended Plan
which would directly or indirectly adversely affect any Participant shall be
effective if adopted at any time without the Participant's written consent.

     7.3 SUCCESSORS. The obligations of the Company under the Amended Plan shall
be binding upon any assignee or successor in interest thereto. The Company shall
not merge, consolidate or combine with any other corporation, or liquidate or
dissolve, without making suitable arrangements for the payment of any benefits
which are or may become payable under the Amended Plan.

                                    SECTION 8

                                  MISCELLANEOUS

     8.1 MITIGATION AND SET-OFF. No Participant shall be required to mitigate
the amount of any payment provided for in this Amended Plan by seeking other
employment or otherwise. The Company shall not be entitled to set off against
the amounts payable to any Participant under this Amended Plan any amounts
earned by the Participant in other employment after termination of the
Participant's employment with the Company, or any amount which might have been
earned by the Participant in other employment had he sought such other
employment.

     8.2 NON-ALIENATION. Participants shall not have any right to pledge,
hypothecate, anticipate or in any way create a lien upon any amounts provided
under this Amended Plan; and no benefits payable hereunder shall be assignable
in anticipation of payment either by voluntary or involuntary acts or by
operation of law. Nothing in this Section shall limit a Participant's rights or
powers to dispose of the Participant's property by will or limit any rights or
powers which the Participant's executor or administrator would otherwise have.

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     8.3 WITHHOLDING. All payments to a Participant under this Amended Plan will
be subject to all applicable withholding of state and federal taxes.

     8.4 SOURCE OF PAYMENTS. The obligations of the Company under the Amended
Plan are solely contractual, and any amount payable under the terms of the
Amended Plan shall be paid from the general assets of the Company or from one or
more trusts, the assets of which are subject to the claims of the Company's
general creditors. However, the obligations under this Amended Plan have been
approved by Order of the Court and therefore create post petition administrative
priority claims for payment by the Company.

     8.5 NOTICES. Any notice or document required to be given under the Amended
Plan shall be considered to be given if actually delivered or mailed by
certified mail, postage prepaid, if to the Company, to the General Counsel of
the Company at the Company's principal business address or, if to a Participant,
at the last address of such Participant filed with the Company.

     8.6 GENDER AND NUMBER. Where the context permits, words in any gender shall
include any other gender, words in the singular shall include the plural, and
the plural shall include the singular.

     8.7 NO RIGHT TO EMPLOYMENT OR CONTINUATION OF RELATIONSHIP. Nothing in this
Amended Plan shall confer upon or be construed as giving any Participant any
right to remain in the employ of the Company. All Participants' employment with
the Company is and will at all times remain "at will". The Company may at any
time dismiss a Participant from employment free from a liability or any claim
except as expressly provided in this Amended Plan. No employee of the Company
shall have any claim to be designated a Participant and there is no obligation
for uniformity of treatment of any employee of the Company.

     8.8 GOVERNING LAW. EXCEPT AS TO MATTERS RELATING TO THE INTERNAL AFFAIRS OF
THE COMPANY WHICH SHALL BE GOVERNED BY THE DELAWARE GENERAL CORPORATION LAW, THE
VALIDITY, CONSTRUCTION AND EFFECT OF THIS AMENDED PLAN AND ANY RULES AND
REGULATIONS RELATING TO THIS AMENDED PLAN SHALL BE DETERMINED IN ACCORDANCE WITH
THE LAWS OF THE STATE OF TEXAS, WITHOUT GIVING EFFECT TO THE CONFLICT OF LAWS
PRINCIPLES THEREOF AND WILL, TO THE MAXIMUM EXTENT PRACTICABLE, BE DEEMED TO
CALL FOR PERFORMANCE IN DALLAS COUNTY, TEXAS.

     8.9 SEVERABILITY. If any provision of this Amended Plan is or becomes or is
deemed to be invalid, illegal or unenforceable in any jurisdiction or as to any
individual Participant, or would disqualify this Amended Plan under any law
deemed applicable by the Board, such provision shall be construed or deemed
amended to conform to applicable law, or if it cannot be construed or deemed
amended without, in the sole determination of the Board, materially altering the
intent of this Amended Plan, such provision shall be stricken as to

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such jurisdiction or Participant and the remainder of this Amended Plan shall
remain in full force and effect.

     8.10 NO LIMITATION UPON THE RIGHTS OF THE COMPANY. This Amended Plan shall
not affect in any way the right or power of the Company to make adjustments,
reclassifications, or changes of its capital or business structure; to merge,
convert or consolidate; to dissolve or liquidate; or sell or transfer all or any
part of its business or assets.

     8.11 NO LIABILITY FOR GOOD FAITH DETERMINATIONS. The members of the Board
shall not be liable for any action, failure to act, omission or determination
taken or made in good faith with respect to this Amended Plan.

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                                    EXHIBIT A

                             PARTICIPATION AGREEMENT

     You have been designated by the Board of Directors as a Participant in the
WebLink Wireless, Inc. Amended Key Employee Retention Plan (the "Amended Plan")
with the following Retention Percentage and total Base Amount:

     Name of Participant:
                          -----------------------------------------
     Position:
               ----------------------------------------------------
     Annual Rate of Salary:
                            ---------------------------------------
     Target Bonus Percentage Rate:
                                   --------------------------------
     Retention Percentage:
                           ----------------------------------------
     Retention Bonus:
                      ---------------------------------------------
     Number of Months of Payment: 12

     Your participation in the Amended Plan is subject to your (i) execution of
a Release of Claims in form and substance reasonably acceptable to the Company
and (ii) agreement with the express terms and conditions of this Amended Plan.
By signing below, you agree to be bound by the terms and conditions of the
Amended Plan, and represent that you have voluntarily executed the
aforementioned Release of Claims, and received a copy of the Amended Plan. You
further agree and understand that this Amended Plan supersedes the previous Key
Employee Retention Plan you signed on ________________.

     Dated as of                  .
                 -----------------

                                           WEBLINK WIRELESS, INC.

                                       By:
                                           --------------------------------

                                       Title:
                                              -----------------------------

Participant:


-----------------------------------
Signature


-----------------------------------
Printed Name

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