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                                                   CONTRACT NUMBER: C949017S0001









                              AMENDED AND RESTATED
                       STRATEGIC ALLIANCE AGREEMENT NO. 1

                                     BETWEEN

                    GTE COMMUNICATION SYSTEMS CORPORATION

                                      AND

                             PAGEMART WIRELESS, INC.










                                                CONTRACT MANAGER: GALE L. MARVIN


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                                TABLE OF CONTENTS

<TABLE>
<S>                                                        <C>
1.  RECITALS...............................................1

2.  DEFINITIONS............................................1

3.  DESCRIPTION AND SCOPE..................................2

4.  TERM...................................................2

5.  TERMINATION............................................3

6.  GTE RESPONSIBILITIES...................................4

7.  PMWI RESPONSIBILITIES..................................5

8.  OWNERSHIP OF ONE-WAY FACILITIES AND FREQUENCIES........6

9.  GTE SITES..............................................7

10. CONFIDENTIAL INFORMATION...............................7

11. DISPUTE RESOLUTION.....................................8

12. GENERAL PROVISIONS.....................................9

13. MAINTENANCE AND REPAIRS AT GTE OWNED SITES............14

14. SIGNATURES............................................15
</TABLE>




                                                                  -CONFIDENTIAL-
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                              AMENDED AND RESTATED
                       STRATEGIC ALLIANCE AGREEMENT NO. 1


     THIS AMENDED AND RESTATED STRATEGIC ALLIANCE AGREEMENT NO. 1 ("Agreement")
is made by and between PageMart Wireless, Inc., a Delaware corporation, with
offices for the purpose of this Agreement located at 3333 Lee Parkway, Suite
100, Dallas, Texas 75219 ("PMWI") and GTE Communication Systems Corporation, a
Delaware corporation, acting for the benefit of itself and its affiliates listed
in Exhibit A, with offices located at 700 Hidden Ridge, Irving, Texas 75038
("GTE") (collectively referred to as the "Parties" and individually as a
"Party").

1.   RECITALS

     The Parties recognize the mutual benefits to be gained if they cooperate in
     the deployment of paging network facilities in the continental United
     States ("CONUS") for the provision of wireless messaging and data
     transmissions.

     This Agreement is intended to create a framework and to define the terms
     and conditions under which the Parties shall implement their strategic
     alliance in a manner that maximally complements the wireless needs of the
     Parties.

     IN CONSIDERATION of the above Recitals, the terms and provisions set forth
     herein, the mutual benefits to be gained by the performance thereof, and
     for the good and valuable consideration, the receipt and sufficiency of
     which are hereby acknowledged, the Parties hereto agree as follows:

2.   DEFINITIONS

     Facilities - Both One-Way Facilities and NPCS Facilities

     CONUS - The 48 continental United States

     NPCS - (Narrowband PCS) - NPCS services operating in the 901-902 MHz,
     930-931, and 940-941 MHZ bands.

     NPCS FACILITIES - Equipment to be integrated into PMWI's network
     infrastructure for transmission and receipt of NPCS messages which shall
     include but not be limited to NPCS paging transmitters and receivers,
     satellite downlinks and cable deployed for the transmitting and receiving
     of two way paging messaging services.

     One-Way Facilities - The GTE-supplied wireless network infrastructure which
     shall include but not be limited to paging transmitters, satellite
     downlinks, antennas, and cable being deployed to PMWI for the transmission
     of one-way paging/messaging services

     Project - The site specific installation function of NPCS or One-Way
     Facilities

     PCS - (Personal Communications Service) - Radio communications that
     encompass mobile and ancillary fixed communication that provide services to
     individuals and businesses and can be integrated with a variety of
     competing networks.


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     RSA - Resale Agreement No. C989107SC001 previously entered into between the
     Parties.

     Termination Date - That date which is twenty-four (24) months from either
     the date of notification of termination or the expiration date because of
     non-renewal.

     THIRD PARTY SITES - Telecommunications transmission sites owned by or
     beneficially belonging to a party other than GTE, notwithstanding Section
     3.e., on which One-Way Facilities have been constructed.

3.   DESCRIPTION AND SCOPE

     a.   This Agreement will govern the cooperation of the Parties in
          connection with any Project in CONUS involving, without limitation,
          the location, design, construction, and management of all One-Way
          Facilities, and where specified, all NPCS Facilities. The Parties
          agree that the deployment scope of the One-Way Facilities shall be no
          less than one hundred fifty (150) and no more than two hundred fifty
          (250) transmitters deployed within the first twenty-four (24) months
          of this Agreement.

     b.   All telecommunications and wireless services that are the subject of
          this Agreement shall be provided in accordance with the rules,
          regulations and orders of the applicable state regulatory agency, the
          Federal Communications Commission ("FCC") and the courts of the United
          States.

     c.   The obligations of the Parties to cooperate and work together in
          connection with any Project shall be as expressly set forth in this
          Agreement. Neither Party undertakes by this Agreement or otherwise to
          perform or discharge any liability or obligation for the other Party
          not specifically contained herein, whether regulatory or contractual,
          or to assume any responsibility whatsoever for the conduct of the
          business or operations of the other Party. Nothing contained herein is
          intended to give rise to a partnership or joint venture between the
          Parties or to impose upon the Parties any of the duties or
          responsibilities of partners or joint venturers. Neither Party shall
          have any right or authority to act for, or to assume, create or incur
          any obligation, liability or responsibility of any kind, whether
          express or implied, against, in the name of, or on behalf of, the
          other Party, except as expressly provided in this Agreement.

     d.   Unless otherwise specified herein, each Party shall assume and bear
          all expenses, costs and fees incurred or assumed by such Party whether
          or not the transactions provided for by this Agreement shall be
          effectuated.

     e.   Any sites that are owned by GTE Wireless, Incorporated on which
          One-Way Facilities are located shall be considered Third Party Sites
          for the purposes of this Agreement.

4.   TERM

     The term of this Agreement commenced on September 15, 1994 and shall end on
     December 31, 2004, unless earlier terminated in accordance with Section 5.
     The term of this Agreement may be extended for successive one-year periods




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     following the expiration of the initial term by mutual written consent of
     the Parties at least ninety (90) days prior to the end of the then current
     term.

5.   TERMINATION

     a.   Termination for Cause. This Agreement may be abandoned or terminated
          at any time after the effective date of this Agreement by either
          Party's furnishing written notice should the other Party:

          i.   breach, refuse or fail in any material respect properly to
               perform any of its duties, obligations or commitments under this
               Agreement, any one of which shall constitute a default, which
               default is not substantially cured within thirty (30) days after
               receiving written notice specifying the nature of the default;

          ii.  commence or have commenced against such Party any proceeding,
               whether under court supervision or otherwise, for the liquidation
               of such Party, determination of insolvency of such Party,
               appointment of a receiver for such Party, assignment for the
               benefit of all or substantially all of such Party's creditors, or
               the bankruptcy of such Party; or

          iii. indefinitely suspend its normal business operations.

          If this Agreement is terminated by GTE as a result of PMWI's conduct
          described in this Section 5 (a), then Section 5.b.i.(1) and (2) below
          shall be enforced between the Parties. If this Agreement is terminated
          by PMWI as a result of GTE's conduct described in this Section 5 (a),
          then Section 5.b.ii.(1) and (2) below shall be enforced between the
          Parties.

     b.   Termination for Convenience. This Agreement may be abandoned or
          terminated at any time after the effective date of this Agreement, by
          either party, subject to the following:

          i.   If this Agreement is terminated for convenience by PMWI:

               (1)  PMWI shall make a payment to GTE based upon the following
                    formula, per piece of equipment, using a life span of five
                    (5) years. P=C x (1-t/60) where P represents PMWI's payment
                    to GTE, C represents GTE's investment in the equipment, and
                    t represents the time period in months (1-60) that the piece
                    of equipment has been in service as of the Termination Date.
                    No equipment will be transferred from GTE to PMWI because of
                    this payment; and

               (2)  PMWI will be given the option to purchase the One-Way
                    Facilities at fair market value as of the Termination Date.

          ii.  If this Agreement is terminated for convenience by GTE:

               (1)  GTE shall make a payment to PMWI based upon the following
                    formula, per piece of equipment, using a life span of five
                    (5) years. P=R x (1-t/60) where P represents GTE's payment
                    to PMWI, R




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                    represents the cost of relocating the pieces of equipment
                    residing on GTE property, and it represents the time period
                    in months (1-60) that the piece of equipment has been in
                    service as of the Termination Date; and

               (2)  PMWI shall be given the right to purchase the equipment
                    based upon the greater of ten percent (10%) of the
                    equipment's original cost or a calculated value utilizing
                    the formula P=C x (1-t/60) where P represents the purchase
                    price, C represents GTE's investment in the piece of
                    equipment, and it represents the time period in months
                    (1-60) that the piece of equipment has been in service as of
                    the Termination Date.

     c.   Termination of the RSA. If the RSA is terminated by:

          i.   PMWI in accordance with Section 28(a) of said RSA, this
               Agreement shall also terminate, and Section 5.b.i.(1) above shall
               be enforced between the Parties.

          ii.  GTE as a result of PMWI's conduct under Section 28(b) or (c) of
               said RSA, this Agreement shall also terminate, and Section
               5.b.i.(1) and (2) above shall be enforced between the Parties.

          iii. PMWI as a result of GTE's conduct under Section 28(b) or (c) of
               said RSA, this Agreement shall also terminate, and Section 5.b.ii
               (1) and (2) above shall be enforced between the Parties.

     d.   If this Agreement is either terminated in accordance with this Section
          or not renewed, PMWI agrees to keep the One-Way Facilities operating
          in a normal capacity until the Termination Date and GTE agrees to
          permit PMWI to leave any equipment located on GTE property through the
          Termination Date.

     e.   The termination of this Agreement shall not affect any obligation of a
          Party which is unfulfilled as of such termination provided that such
          obligation by its terms or nature survives such termination.

6.   GTE RESPONSIBILITIES

     a.   For any Project, GTE shall have the final responsibility, subject to
          the consent of PMWI which shall not be unreasonably withheld, of
          determining when and where the One-Way Facilities shall be
          constructed.

     b.   For any One-Way Project, GTE shall, at its sole cost and expense,
          finance the construction of One-Way Facilities on which PMWI would
          utilize PMWI's frequencies to provide wireless services to PMWI's
          customers and to GTE as a reseller of PMWI's wireless services.

     c.   In conjunction with the construction of any One-Way Facilities, GTE
          shall be financially responsible for purchasing any transmitters,
          antennae, satellite downlink, cable, and third party labor necessary
          to install the One-Way Facilities.



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     d.   For any One-Way Project, GTE shall be responsible for payment of all
          property taxes, whether real or personal, on all One-Way Facilities
          that may be imposed or assessed by any appropriate taxing authority.

     e.   GTE shall be responsible for payment of monthly site lease or license
          fees to a maximum amount of $400 per month per site for fifty percent
          (50%) of the total One-Way Project sites. GTE shall be given credit
          for any sites located on property owned or leased by GTE. GTE's
          monthly total site lease obligations shall be calculated using the
          following formula: 0=$400 x (.5T-N), where 0 is equal to GTE's
          obligation, T is equal to the total number of sites and N is equal to
          the number of sites owned by GTE (GTE Network Services or its
          successor). GTE will remit payment directly to PMWI for such site
          lease obligation within thirty (30) days of receipt of an invoice for
          same. This per month per site charge shall be increased on the
          anniversary of this Agreement each year of this Agreement by five
          percent (5%).

7.   PMWI RESPONSIBILITIES

     a.   For any Project, PMWI shall be solely responsible for conducting any
          propagation studies at PMWI's expense.

     b.   For any Project, PMWI, shall license the One-Way Facilities at
          locations selected by GTE as described in Section 6.a. herein, to
          utilize PMWI's nationwide frequencies to provide wireless services to
          PMWI's customers and to GTE as a reseller of PMWI's wireless
          services.

     c.   To the extent that any One-Way Facilities may be located on Third
          Party Sites, PMWI shall be solely responsible for negotiating the
          terms and conditions of any lease or license, any expenses associated
          with lease site preparation which shall include but not be limited to
          shelter construction and provisioning of electrical power and for the
          remittance of any operating expenses associated with that lease or
          license. The terms and conditions of any such lease or license should
          contain authorization that GTE, subject to prior notification, shall
          have reasonable access during normal working hours to visit and
          inspect the One-Way Facilities.

     d.   Although GTE and PMWI shall jointly agree on the selection of
          contractors to construct and maintain all One-Way Facilities of any
          Project, PMWI shall be responsible, at its sole cost and expense, for
          managing, coordinating and overseeing the construction and maintenance
          of all Facilities.

     e.   At PMWI's sole cost and expense, PMWI shall operate all Facilities,
          including, without limitation, the payment for any access connections
          including but not limited to business single party lines and for any
          long distance service necessary for polling all Facilities to ensure
          all Facilities are operational, in a good state of repair, and
          operating according to manufacturers specifications.

     f.   At PMWI's sole cost and expense, PMWI shall utilize PMWI's national
          control center to provide monitoring, ongoing quality assurance and
          maintenance, and local repair dispatch services for all Facilities
          covered by this Agreement. PMWI shall additionally be responsible for
          furnishing any upgrades, whether software or


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          otherwise, reasonably necessary for the operation of all Facilities.


     g.   PMWI shall, at its sole cost and expense, link by satellite all
          Facilities to PMWI's network infrastructure for network control.

     h.   PMWI shall provide a reduction in GTE's monthly billing as a reseller
          of PMWI Services, as authorized by and defined in the RSA, based upon
          the following schedule:

          i.   Two hundred fifty dollars ($250) per month per installed
               transmitter financed by GTE for months number one (1) through
               sixty (60) of this Agreement.

          ii.  One hundred dollars ($100) per month per installed transmitter
               financed by GTE for months number sixty-one (61) through one
               hundred twenty (120) of this Agreement.

          Notwithstanding the foregoing, the Parties agree that at no time shall
          the amount of reduction as calculated above exceed twenty-five percent
          (25%) of the monthly billing GTE receives as a reseller of PMWI
          Services. Should the Parties agree to extend this Agreement beyond its
          initial one hundred twenty (120) month term, the above per month
          billing reduction from PMWI to GTE will be renegotiated at that time.

     i.   For any One-Way or NPCS Project, PMWI will be responsible for payment
          of all monthly site lease or license fees. GTE shall reimburse PMWI
          for fifty percent (50%) of any such One-Way site lease fees as set
          forth in Section 6.e. above.

     j.   For any NPCS Project, PMWI shall be responsible for all capital
          expenses involved in the purchase of, installation of, and
          construction of any NPCS Facilities.

     k.   For any NPCS Project, PMWI shall be responsible for all property
          taxes, whether real or personal, on all NPCS Facilities that may be
          imposed or assessed by any appropriate taxing authority.

     l.   PMWI agrees to reimburse GTE the amount of four hundred dollars ($400)
          per month for each GTE site on which PMWI has installed NPCS
          Facilities. This monthly site charge shall be increased on the
          anniversary of this Agreement each year of this Agreement by five
          percent (5%).

8.   OWNERSHIP OF ONE-WAY FACILITIES AND FREQUENCIES

     a.   GTE shall have legal title to and shall be the exclusive owner of all
          One-Way Facilities whether the property constituting the One-Way
          Facilities shall be characterized as real or personal. PMWI, at its
          expense, will defend GTE's rights to the One-Way Facilities and will
          keep the One-Way Facilities free from all liens, encumbrances, and
          legal processes, other than those arising out of actions of GTE. GTE
          shall be permitted to display notice of its ownership of the One-Way
          Facilities by affixing to the items of the One-Way Facilities indicia
          of ownership and PMWI agrees not to remove, alter, or obscure said
          identification. PMWI grants to GTE a security interest in PMWI's
          interest in the One-Way Facilities subject to this



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          Agreement and agrees to execute all documents necessary to perfect
          said security interest.

     b.   Notwithstanding the foregoing, PMWI and GTE understand and agree that
          the nationwide frequencies upon which PMWI furnishes the wireless
          services provided for herein are licensed exclusively to PMWI. Nothing
          contained herein shall permit GTE to disconnect the transmitters,
          antennae or other equipment or remove any of such assets from any
          Facility sites during the term of this Agreement without prior written
          permission from PMWI, such permission not to be unreasonably withheld.

     c.   PMWI shall have legal title to or the equitable right to control NPCS
          Facilities whether the property constituting the NPCS Facilities shall
          be characterized as real or personal. PMWI shall be permitted to
          display notice of its ownership of the NPCS Facilities by affixing to
          the items of the NPCS Facilities indicia of ownership and GTE agrees
          not to remove, alter, or obscure said identification.

9.   GTE SITES

     GTE shall furnish certain sites owned or leased by GTE to PMWI for the
     installation of the Facilities and provision of wireless services to PMWI's
     customers and to GTE as a reseller of PMWI's wireless services at no cost
     to PMWI until the Termination Date. In performing its obligations under
     this Agreement, PMWI shall comply with all reasonable rules and
     regulations, which shall be mutually agreed to and established by the
     Parties, with respect to access to and use of the GTE sites. GTE's
     obligation to pay site lease or license fees shall be reduced by the number
     of sites owned or leased by GTE or as set forth in Section 6.e above.

10.  CONFIDENTIAL INFORMATION

     a.   To effectuate this Agreement, it may be necessary for either Party to
          disclose to the other proprietary or confidential customer, technical
          and business information in written, graphic, oral or other tangible
          or intangible forms ("Confidential Information"). In order to protect
          such Confidential Information from improper disclosure, each party
          agrees: (1) that all such Confidential Information shall be and shall
          remain the exclusive property of the source; (2) to limit access to
          such Confidential Information to authorized employees who have a need
          to know the Confidential Information in order to perform the services
          set out in this Agreement; (3) to keep such Confidential Information
          confidential and to use the same level of care to prevent disclosure
          or unauthorized use of the received Confidential Information as it
          exercises in protecting its own Confidential Information of a similar
          nature; (4) for a period of three years following any disclosure, not
          to copy or publish or disclose such Confidential Information to others
          or authorize anyone else to copy or publish or disclose such
          Confidential Information to others without the prior written approval
          of the source; (5) to return promptly any copies of such Confidential
          Information to the source at its request; and (6) to use such
          Confidential Information only for purposes of fulfilling work or
          services performed hereunder and for other purposes only upon such
          terms as may be agreed upon between the parties in writing.


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     b.   These obligations shall not apply to any Confidential Information
          which was legally in the recipient's possession prior to receipt from
          the source, was received in good faith from a third party not subject
          to a confidential obligation to the source, now is or later becomes
          publicly known through no breach of confidential obligation by the
          recipient, was developed by the recipient without the developing
          person(s) having access to any of the Confidential Information
          received in confidence from the source, or which is required to be
          disclosed pursuant to subpoena or other process issued by a court or
          administrative agency having appropriate jurisdiction. If a receiving
          party receives a request to disclose any Confidential Information
          (whether pursuant to a valid and effective subpoena, an order issued
          by a court or other governmental authority of competent jurisdiction
          or otherwise) on advice of legal counsel that disclosure is required
          under applicable law, such party agrees that, prior to disclosing any
          Confidential Information, it shall (i) notify the disclosing party of
          the existence and terms of such request or advice, (ii) cooperate with
          the disclosing party in taking legally available steps to resist or
          narrow any such request or to otherwise eliminate the need for such
          disclosure, if requested to do so by the disclosing party, and (iii)
          if disclosure is required, use its best efforts to obtain a protective
          order or other reliable assurance that confidential treatment will be
          afforded to such portion of the Confidential Information as is
          required to be disclosed. The disclosing party shall reimburse the
          other party for its reasonable expenses, including attorney fees, in
          exerting best efforts in complying with b (ii) and b (iii).

     c.   The obligation of confidentiality and use with respect to Confidential
          Information disclosed by one party to the other shall survive any
          termination of this Agreement for a period of three years from the
          date of the initial disclosure of the Confidential Information.

11.  DISPUTE RESOLUTION

     a.   The Parties desire to resolve disputes arising out of this Agreement
          without litigation. Accordingly, except for action seeking a temporary
          restraining order or injunction related to the purposes of this
          Agreement, or suit to compel compliance with this dispute resolution
          process, the Parties agree to use the following alternative dispute
          resolution procedure as their sole remedy with respect to any
          controversy or claim arising out of or relating to this Agreement or
          its breach.

     b.   At the written request of a Party, each Party will appoint a
          knowledgeable, responsible representative to meet and negotiate in
          good faith to resolve any dispute arising under this Agreement. The
          Parties intend that these negotiations be conducted by nonlawyer,
          business representatives. The location, format, frequency, duration
          and conclusion of these discussions shall be left to the discretion of
          the representatives. Upon agreement, the representatives may utilize
          other alternative dispute resolution procedures such as mediation to
          assist in the negotiations. Discussions and correspondence among the
          representatives for purposes of these negotiations shall be treated as
          confidential information developed for purposes of settlement, exempt
          from discovery and production, which shall not be admissible in the
          arbitration described below or in any lawsuit without the concurrence
          of all Parties. Documents identified in or provided with such
          communications, which are not prepared for purposes of the
          negotiations, are not


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          so exempted and may, if otherwise admissible, be admitted in evidence
          in the arbitration or lawsuit.

     c.   If the negotiations do not resolve the dispute within sixty (60) days
          of the initial written request, the dispute shall be submitted to
          binding arbitration by a single arbitrator pursuant to the Commercial
          Arbitration Rules of the American Arbitration Association. A Party may
          demand such arbitration in accordance with the procedures set out in
          those rules. Discovery shall be controlled by the arbitrator and shall
          be permitted to the extent set out in this Section. Each Party may
          submit in writing to a Party, and that Party shall so respond, to a
          maximum of any combination of thirty-five (35) (none of which may have
          subparts) of the following: interrogatories, demands to produce
          documents, and requests for admission. Each Party is also entitled to
          take the oral deposition of one individual of another Party.
          Additional discovery may be permitted upon mutual agreement of the
          parties. The arbitration hearing shall be commenced within sixty (60)
          days of the demand for arbitration. The arbitration shall be held in
          the city where this Agreement was executed by GTE. The arbitrator
          shall control the scheduling so as to process the matter
          expeditiously. The Parties may submit written briefs. The arbitrator
          shall rule on the dispute by issuing a written opinion within thirty
          (30) days after the close of hearings. The times specified in this
          Section may be extended upon mutual agreement of the Parties or by the
          arbitrator upon a showing of good cause. Judgment upon the award
          rendered by the arbitrator may be entered in any court having
          jurisdiction.

     d.   Each Party shall bear its own costs of these procedures. A Party
          seeking discovery shall reimburse the responding Party the costs of
          production of documents (to include search time and reproduction
          costs). The Parties shall equally split the fees of the arbitration
          and the arbitrator.

12.  GENERAL PROVISIONS

     a.   Further Assurances. From and after the effective date of this
          Agreement, the Parties each agree to execute and deliver such further
          documents and instruments and to do such further acts and things as
          the other may reasonably request in order to effectuate the
          transactions contemplated by this Agreement. The Parties shall
          cooperate and assist one another in the performance of the provisions
          of this Agreement, and shall take such steps as are reasonably
          necessary to allow the other Party to discharge the obligations
          imposed by this Agreement.

     b.   Excusable Delays. Neither Party shall be liable for any delay or
          failure in its performance of any of the acts required by this
          Agreement when such delay or failure arises beyond the reasonable
          control of such Party. Such causes may include, without limitation,
          acts of God or public enemies, labor disputes, material or component
          shortages, supplier failures, embargoes, rationing, acts of local,
          state or national governments or public agencies (not solicited,
          encouraged or invited by any Party), utility or communication failures
          or delays, fires, floods, epidemics, riots and strikes. The time for
          performance of any act delayed by such cause shall be postponed for a
          period equal to the delay; provided, however, that the Party so
          affected shall give prompt notice to the other Party of such delay.
          The Party so affected, however, shall use its best efforts to avoid or
          remove such causes of nonperformance to complete performance of the
          act delayed, whenever such causes are removed.



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<PAGE>   12
     c.   Assignment. Neither this Agreement nor any of the rights hereunder may
          be assigned or otherwise transferred by any Party, by operation of law
          or otherwise, without the prior written consent of the other Party,
          except that the Parties may, without obtaining such consent, assign
          their respective obligations and rights hereunder to their parent, or
          any other subsidiary of a parent, eighty percent (80%) or more of the
          voting stock of which is owned by the parent. In any case of
          assignment, however, the assignee shall assume all obligations of the
          assigning Party hereunder and the other Party shall have received
          documents satisfactory in form and substance to it evidencing such
          assumption. Any such assignment shall not relieve any Party to this
          Agreement of its obligations hereunder, and any such assignee may,
          upon the terms and conditions, reassign its rights hereunder to such
          original Party or to any assignee of such original Party permitted
          hereunder.

     d.   Successors in Interest. All provisions of this Agreement shall be
          binding upon, inure to the benefit of, and be enforceable by and
          against the respective successors and assigns of the Parties or
          purchasers of substantially all of the assets of a Party.

     e.   Independent Contractor Relationship. The persons provided by each
          Party shall be solely that Party's employees or agents and shall be
          under the sole and exclusive direction and control of that Party. They
          shall not be considered employees of the other Party for any purpose.
          Each Party shall remain an independent contractor with respect to the
          other and shall be responsible for compliance with all laws, rules and
          regulations involving, but not limited to, employment of labor, hours
          of labor, health and safety, working conditions and payment of wages.
          Each Party shall also be responsible for payment of taxes, including
          federal, state and municipal taxes, chargeable or assessed with
          respect to its employees, such as, Social Security, unemployment,
          Workers' Compensation, disability insurance, and federal and state
          withholding. Each Party shall indemnify the other for any loss,
          damage, liability, claim, demand or penalty that may be sustained by
          reason of its failure to comply with this provision.

     f.   Publicity. Any news release, public announcement, advertising or any
          form of publicity pertaining to this Agreement, provision of services
          pursuant to it, or association of the Parties with respect to the
          subject of this Agreement shall be subject to prior written approval
          of both parties.

     g.   Trademarks and Trade Names. Except as specifically set out in this
          Agreement, nothing in this Agreement shall grant, suggest or imply any
          authority for one Party to use the name, trademarks, service marks or
          trade names of the other for any purpose whatsoever.

     h.   Records. Each Party shall keep true and accurate records directly
          relating to this Agreement in accordance with generally accepted
          accounting practices. Such records shall be retained for a period of
          three (3) years from the Termination Date.

     i.   Attorney's Fees. Except as set forth in Section 11, in the event any
          Party to this Agreement shall be required to initiate legal
          proceedings (i) to interpret or to enforce performance of any term or
          condition of this Agreement; (ii) to enjoin any action



                                       10
<PAGE>   13
          prohibited hereunder; or (iii) to gain any other form of relief
          whatsoever, the prevailing Party shall be entitled to get such sums
          from the other Party, in addition to any other damages or compensation
          received, as well as reimbursement from the other Party for reasonable
          attorneys' fees and court costs incurred on account thereof
          notwithstanding the nature of the claim or cause of action asserted by
          the prevailing Party.

     j.   Indemnification. Notwithstanding anything to the contrary herein, each
          Party shall indemnify and save harmless the other from any loss or
          damages (including reasonable attorney's fees) incurred by the other
          because of claims, suits, or demands based on personal injury or death
          or damage to property, including, without limitation, all Facilities,
          or third party claims, suits or demands of any kind, to the extent
          such loss or damage is caused by or results from the negligent or
          willful acts or omissions of the other or its employees or agents. The
          indemnifying Party shall receive the full opportunity and authority to
          assume the sole defense of and settlement of such suits. The
          indemnified Party agrees to furnish to the indemnifying Party upon
          request all information and reasonable assistance available to the
          indemnified party for defense against any such suit, claim, or demand.

     k.   Insurance. GTE and PMWI each agree to maintain during the term hereof
          all insurance and/or bonds required by law or this Agreement,
          including, but not limited to (1) Workers' Compensation and related
          insurance as prescribed by applicable law; (2) employer's liability
          insurance with limits of at least $500,000 for each occurrence; and
          (3) comprehensive general liability insurance including products
          liability, and, if the use of motor vehicles is required,
          comprehensive motor vehicle liability insurance, each with limits of
          at least $2,000,000 for combined single limit for bodily injury,
          including death, and/or property damage. GTE and PMWI each shall cause
          the other to be included as an Additional Insured under their
          respective policies and GTE's and PMWI's appropriate coverage under
          such policies shall be primary. GTE and PMWI each shall furnish
          certificates or evidence of the foregoing insurance indicating the
          amount and nature of such coverage, the expiration date of each
          policy, and stating that no material change or cancellation of any
          such policy shall be effective unless thirty (30) days advance written
          notice is given to the Party named as an Additional Insured.
          Notwithstanding the above, GTE and PMWI shall each have the option,
          where permitted by law, to self-insure any or all of the foregoing
          risks.

     l.   Assuring Performance of Responsibilities. Notwithstanding anything
          stated or implied to the contrary elsewhere in this Agreement, GTE
          may, as permissible under FCC rules and regulations, at its option and
          without prejudice to other rights, take over and complete all or part
          of PMWI's responsibilities with respect to the One-Way Facilities if
          PMWI has defaulted, which default is not substantially cured within
          thirty (30) days of receiving written notice of the default, or PMWI
          has not furnished GTE with adequate assurance that PMWI is prepared to
          perform its obligations in a timely fashion and/or as required by this
          Agreement. PMWI shall be liable to GTE for any costs incurred by GTE
          in discharging PMWI's responsibilities. If, in GTE's reasonable
          opinion, a hazardous condition exists at any Facility, GTE may without
          notice to PMWI take such immediate action as is necessary to protect
          persons, the Facilities or the property of third parties from damage
          or interference caused by the hazard.



                                       11
<PAGE>   14
     m.   Rights and Remedies. The rights and remedies provided each of the
          Parties herein shall be cumulative and in addition to any other rights
          and remedies provided by law or otherwise. Any failure in the exercise
          by any Party of its rights to enforce any provision of this Agreement
          for any default or violation by another Party shall not prejudice such
          Party's right of enforcement for any further or other default or
          violation.

     n.   Limitation of Liability. It is expressly understood that neither Party
          makes any warranty to the other with respect to the performance or
          fitness for any purpose of the products or services contemplated by
          this Agreement. Each Party's liability to the other for any loss,
          cost, claim, injury, liability or expense, including reasonable
          attorney's fees, relating to or arising out of any negligent act or
          omission in its performance of obligations arising out of this
          Agreement, shall be limited to the amount of direct damage actually
          incurred. Absent gross negligence or knowing and willful misconduct
          which causes a loss, neither Party shall be liable to the other for
          any indirect, special or consequential damage of any kind whatsoever.
          For purposes of this clause, payments and related expenses for third
          party claims, suits or demands for which indemnity is owed shall be
          considered direct damages.

     o.   Limitation of Actions. No action, regardless of form, arising out of
          the subject matter of this Agreement may be brought by either Party
          more than two (2) years after the cause of action has accrued. The
          Parties waive the right to invoke any different limitation on the
          bringing of actions provided under state law.

     p.   Notices. All notices and other communications required or permitted to
          be given under this Agreement shall be in writing and shall be
          effective when delivered personally, or if by telex or TWX, when
          confirmed (which confirmation may be by reply telex or signal
          indicating that the message has been clearly received) or if mailed,
          five (5) days after mailing, postage prepaid and addressed to the
          Parties at their respective addresses set forth below, unless by such
          notice a different person, address or number shall have been
          designated for giving notice hereunder:

          If to GTE:         GTE Communication Systems Corporation
                             700 Hidden Ridge
                             Irving, Texas 75038
                             Attn: Manager-Contract Management
                             Mail Code: HQWO3N56

          If to PMWI:        PageMart Wireless, Inc.
                             3333 Lee Parkway
                             Suite 100
                             Dallas, Texas 75219
                             Attn: Vice President Carrier Services Division



     q.   Waiver. The waiver by a Party of the performance of any covenant,
          condition, obligation, representation, warranty or promise in this
          Agreement shall not invalidate this Agreement or be deemed a waiver by
          such Party of any other covenant, condition, obligation,
          representation, warranty or promise. The waiver of a Party of the time
          for performing any act or condition hereunder does not constitute a
          waiver


                                       12

<PAGE>   15

          of the act or condition itself.

     r.   Construction. None of the provisions of this Agreement shall be for
          the benefit of or enforceable by any third Party. No third Party,
          including any creditor of either Party, shall have any rights against
          the Parties or any of their subsidiaries, successors or assigns by
          reason of or under this Agreement.

     s.   Severability. In the event that any one or more provision(s) contained
          in this Agreement should for any reason be held to be unenforceable in
          any respect, such unenforceability shall not affect any other
          provision of this Agreement, and this Agreement shall be construed as
          if such unenforceable provision(s) had not been contained herein.

     t.   Survival of Obligations. The respective obligations of the Parties
          under this Agreement which by their nature would continue beyond the
          termination, cancellation or expiration hereof, shall survive
          termination, cancellation or expiration hereof.

     u.   Headings. The captions of Articles and Sections of this Agreement are
          inserted only as a matter of convenience and in no way define, limit,
          extend or describe the scope of this Agreement or the intent of any
          provision hereof.

     v.   Compliance with Laws and Regulations. The Parties shall comply with
          all foreign, federal, state and local laws and regulations applicable
          to their performance as described in this Agreement.

     w.   Applicable Law. This Agreement is made and executed in the state of
          Texas and the laws and decisions of Texas, without reference to
          provisions covering conflicts of laws, shall control the construction,
          interpretation, validity and enforcement of this Agreement.

     x.   Amendments, Modifications and Supplements. Amendments, modifications
          and supplements to this Agreement are allowed and will be binding on
          the Parties after the effective date, provided such amendments,
          modifications and supplements (1) are in writing, signed by an
          authorized representative of both parties, and (2) by reference
          incorporate this Agreement and identify the specific Sections or
          clauses contained herein which are amended, modified or supplemented
          or indicate that the material is new. The term, "this Agreement" shall
          be deemed to include any future amendments, modifications and
          supplements.

     y.   Entire Agreement. This Agreement, including all Exhibits attached
          hereto, supersede all prior and contemporaneous agreements not
          required or contemplated hereby. This Agreement may not be modified
          except by a writing signed by authorized representatives of the
          Parties.

     z.   Counterparts. This Agreement may be executed in one or more
          counterparts, simultaneously or separately, and each counterpart shall
          be deemed to be an original for all purposes. If the counterparts are
          separately executed, this Agreement shall be deemed executed when each
          Party has signed a copy. Thereafter, the Parties shall exchange signed
          copies of this Agreement for their respective files.


                                       13

<PAGE>   16

13.  MAINTENANCE AND REPAIRS AT GTE OWNED SITES

     a.   PMWI will reimburse GTE for all actual costs incurred (including
          reasonable travel expenses) when escorting PMWI employees to any
          One-Way or NPCS Facilities located at unmanned GTE owned sites. Such
          amount shall not exceed a rate cap of eighty-five dollars ($85) per
          hour, unless overtime or premium time is required, in which case such
          rate cap is not applicable. PMWI agrees to give GTE twenty-four (24)
          hour notice prior to scheduling any such request.

     b.   In the event PMWI requests GTE to perform maintenance or repairs on
          any Facilities, PMWI agrees to provide all parts necessary to complete
          the maintenance or repairs and will compensate GTE one hundred dollars
          ($100) per hour, plus all actual costs incurred (including reasonable
          travel expenses).




                                       14
<PAGE>   17

14.  SIGNATURES

IN WITNESS WHEREOF, the Parties have executed this Agreement on the date or
dates indicated below to be effective when executed by both.



PAGEMART WIRELESS, INC.                    GTE COMMUNICATION SYSTEMS
                                           CORPORATION


By: /s/ TODD A. BERGWALL                   By: /s/ GALE L. MARVIN
   ------------------------------             --------------------------------
Name: Todd A. Bergwall                     Name: Gale L. Marvin
     ----------------------------               ------------------------------
Title: V.P. Law and Regulation             Title: Senior Contract Manager
     ----------------------------               ------------------------------
Date: April 21, 1999                       Date:  April 22, 1999
     ----------------------------               ------------------------------




                                                                         [STAMP]



                                       15
<PAGE>   18

                                    EXHIBIT A

                             GTE AFFILIATED ENTITIES


GENERAL ADMINISTRATION
GTE Corporation
     GTE Finance Corporation
     GTE Investment Management Corporation
     GTE Realty Corporation
         GTE Realty Corporation of Connecticut
         GTER Incorporated
         GTE-TCCA, Inc.
     GTE REinsurance Company Limited (Vermont)
         GTE Life Insurance Company Limited (Bermuda)
     GTE REinsurance Management Limited (Bermuda)
     GTE Service Corporation
     GTE Shareholder Services Incorporated
     GTE VisNet Incorporated

GOVERNMENT SYSTEMS
Contel Federal Systems, Inc.
     GTE Government Systems Corporation
          GTE CyberTrust Solutions Incorporated
          GTE Federal Services Corporation
          GTE Government Systems Overseas Corporation
          GTE Overseas Systems and Services Corporation
          Telecom Systems Incorporated
          Contel Page International Holdings, Inc.
              Contel Page International, Inc.
          Page Europa, S.p.A.
              MTX Italia

     GTE Telecom Incorporated
     GTE Telecom International Incorporated
     GTE Telecom International Systems Corporation
          GTE Telecom Saudi Arabia LTD

INFORMATION SERVICES
GTE Information Services Incorporated
     General Telephone Directory Company C. por A.
     GTE Communications Corporation
     GTE Data Services GmbH
     GTE Directories (Belgium) Limited
     GTE Directories (B) SDN.BHD (Brunei)
     GTE Directories Corporation
         Associated Directory Services-WC, Company
         GTE Directories Distribution Corporation
         GTE Directories Sales Corporation
              GTEX Corporation
     GTE Directories (HK) Limited (Hong Kong)
     GTE Directorios - Republica Dominicana, C. por A.
     GTE Government Information Services Incorporated
     GTE Information Services (UK) Limited (England)
         U S West Polska Sp. Z o.o
     GTE New Media Services Incorporated
     GTE Telecommunications Services Incorporated
     GTE Yellow Pages Publishing Hungary Kft

INTERNETWORKING OPERATIONS
GTE Internetworking Incorporated
GTE Intelligent Network Services Incorporated
BBN Corporation
     BBN International Corporation
     BBN International Sales Corporation
     BBN Securities Corporation
     BBN U.K. Limited
     Bolt Beranek and Newman Corporation
     Realtech Corporation

TELEPHONE OPERATING COMPANIES
GTE Alaska Incorporated
GTE Arkansas Incorporated
GTE California Incorporated
     Contel Advanced Systems, Inc.
GTE Florida Incorporated
     GTE Florida Business Connections Corporation
     GTE Funding Incorporated
GTE Hawaiian Telephone Company Incorporated
     GTE Hawaiian Tel Insurance Company Incorporated
     GTE Hawaiian Tel International Incorporated
     The Micronesian Telecommunications Corporation
          GTE Pacifica Incorporated
GTE Midwest Incorporated
GTE North Incorporated
GTE Northwest Incorporated
     GTE West Coast Incorporated
GTE South Incorporated
GTE Southwest Incorporated
Contel of Minnesota, Inc. d/b/a GTE Minnesota
Contel of the South, Inc. d/b/a GTE Systems of the South
Contel Service Corporation

GTE Anglo Holding Company Incorporated
     La Compagnie de Telephone Anglo-Canadienne/Anglo-
     Canadian Telephone Company
         BC TELECOM Inc.
              Aerotech Specialities Ltd.
              BC TEL
                   Canadian Telephones and Supplies Ltd.
                   ISM Information Systems Management
                   (B.C.) Corporation
              BC TEL Mobility Cellular Inc.
              BC TEL Mobile Ltd.
              BC TEL Properties Inc.
              BC TEL Risk Management Inc.
              BC TEL Systems Support Inc.
              Microtel International Inc.
              SRI Strategic Resources Inc.

         Telecom Leasing Canada (TLC) Limited

         Quebec-Telephone
              QuebecTel Communications Inc.
              QuebecTel Mobilite Inc.
              Quebec Tel International Inc.

GTE Customer Networks, Inc.

GTE Data Services Incorporated
     GTE Data Services International Incorporated



                                      A-1

<PAGE>   19


                                    EXHIBIT A

                             GTE AFFILIATED ENTITIES


GTE Holdings (Canada) Limited
     Compania Dominicana de Telefonos, C. por A.
     (Codetel)
          Quality Telecommunications, C. por A.

GTE International Telephone Incorporated
     Informatica y Telecommunicaciones, C. por A.
     (Dominican Republic)

GTE International Telecommunications Incorporated
     GTE do Brasil Limitada
     GTE Mexico, L.L.C.
     GTE PCS International Incorporated
     GTE Venezuela Incorporated
         VenWorld Telecom, C.A. (Venezuela)
              Compania Anonima Nacional Telefonos de Venezuela (CANTV)
     Prontocel S.A. (Brazil)

GTE Investments Incorporated

GTE London Limited (England)

GTE Main Street Incorporated

GTE Media Ventures Incorporated

ContelVision, Inc.

GTE Enterprise Initiatives Incorporated

GTE Vantage Incorporated

WIRELESS PRODUCTS AND SERVICES
GTE Airfone Incorporated
         GTE Airfone of Canada Incorporated
         GTE Railfone Incorporated
         Mexfone, S.A. de C.V.

GTE Wireless Incorporated
     GTE Mobile Communications Service Corporation
     GTE Mobile Communications International
     Incorporated
     GTE Mobilnet of Asheville Incorporated
     GTE Mobilnet of Danville Incorporated
     GTE Mobilnet of Eastern North Carolina Incorporated
          GTE Mobilnet of Jacksonville Incorporated
               GTE Mobilnet of Jacksonville II Incorporated
          GTE Mobilnet of Wilmington Incorporated
               GTE Mobilnet of Wilmington II Incorporated
     GTE Mobilnet of Fayetteville Incorporated
     GTE Mobilnet of Florence, South Carolina Incorporated
     GTE Mobilnet of North Carolina Incorporated
     GTE Mobilnet of Raleigh Incorporated
     GTE Mobilnet of South Carolina Incorporated
     GTE Mobilnet of the Southeast Incorporated

     GTE Cellular Communications Corporation

     GTE Mobilnet of Cleveland Incorporated
     GTE Mobilnet Sales Corp.
     GTE Mobilnet Service Corp.
         GTE Mobilnet of Austin Incorporated
         GTE Wireless of Houston Incorporated
     GTE Wireless of the Midwest Incorporated
     GTE Wireless of the Pacific Incorporated
         GTE Mobilnet of Clatsop Incorporated

     Contel Cellular International, Inc.
     GTE Mobilnet Holding Incorporated
         GTE Mobilnet of Alabama Incorporated
              GTE Mobilnet of Florence, Alabama Incorporated
         GTE Mobilnet of Chattanooga Incorporated
         GTE Mobilnet of Chattanooga II Incorporated
         GTE Mobilnet of Clarksville Incorporated
         GTE Mobilnet of Gadsden Incorporated
         GTE Mobilnet of Knoxville Incorporated
         GTE Mobilnet of Memphis Incorporated
         GTE Mobilnet of Memphis II Incorporated
         GTE Mobilnet of Nashville Incorporated
         GTE Mobilnet of Tennessee Incorporated
     GTE Mobilnet of Central California Incorporated
         Pinnacles Cellular, Inc.
     GTE Mobilnet of Huntsville Incorporated
     GTE Mobilnet of Illinois Funding Incorporated
     GTE Mobilnet of San Diego Incorporated
     GTE Mobilnet of the Southwest Incorporated
     GTE Wireless of the South Incorporated


OTHER OPERATIONS
GTE China Incorporated
     GTE International Telecommunications Services LLC
         GITS Branch LLC
         GTE Holdings Mexico, S. de R.L. de C.V.
              GTE Data Services-Mexico, S.A. de C.V.
              GTEDS Services-Mexico, S.A. de C.V.
         GTE Supply-Mexico, S.A. de C.V.

GTE Communications Services Incorporated

GTE Leasing Corporation
     GTE Leasing Acceptance Corporation
     Kalama Grain Terminal, Inc.
GTE Products of Connecticut Corporation

     GTE Communication Systems Corporation (GTE Supply)

     GTE International Incorporated
         GTE Far East (Services) Limited
         GTE Overseas Corporation

     GTE Laboratories Incorporated

     GTE Operations Support Incorporated
         GTE Operations do Brasil Comercial Ltda.
         West Indies Telephone Company




                                      A-2

<PAGE>   20
                                    EXHIBIT A

                             GTE AFFILIATED ENTITIES



     Televac, Inc.

GTE Transfer Corporation













                                      A-3