<PAGE>   1
                                                                   EXHIBIT 10.25




                                RESALE AGREEMENT

                                     BETWEEN

                           GTE MOBILNET SERVICE CORP.

                                       AND

                                  PAGEMART, INC.



<PAGE>   2

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                PAGE

<S>                                                               <C>
 1.  TERM                                                         1
 2.  DEFINITIONS                                                  1
 3.  LICENSE                                                      2
 4.  INDEPENDENT PARTIES                                          2
 5.  SCOPE                                                        2
 6.  LICENSOR RESPONSIBILITIES                                    3
 7.  RESELLER RESPONSIBILITIES                                    3
 8.  PUBLIC REGULATION                                            4
 9.  PRICING                                                      4
10.  BILLING                                                      5
11.  TERMS OF PAYMENT                                             5
12.  SPECIAL PROGRAMS                                             5
13.  PRECEDENCE OF DOCUMENTS                                      6
14.  USE OF CONFIDENTIAL INFORMATION                              6
15.  PUBLICITY                                                    7
16.  COMPLIANCE WITH LAWS                                         7
17.  FORCE MAJEURE                                                7
18.  LIABILITY                                                    8
19.  ASSIGNMENT                                                   9
20.  TAXES                                                       10
21.  RECORDS                                                     10
22.  RIGHT OF ACCESS                                             10
</TABLE>


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<PAGE>   3

<TABLE>

<S>                                                              <C>
23.  TERMINATION                                                 11
24.  DISPUTE RESOLUTION                                          12
25.  NOTICES                                                     13
26.  NONWAIVER                                                   14
27.  SEVERABILITY                                                14
28.  SECTION HEADINGS                                            14
29.  SURVIVAL OF OBLIGATIONS                                     14
30.  CHOICE OF LAW                                               14
31.  ENTIRE AGREEMENT                                            14
</TABLE>




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<PAGE>   4

                                RESALE AGREEMENT

This Agreement is made as of the first day of July 1996, by and between
PageMart, Inc., a Delaware corporation, with offices for the purpose of this
Agreement located at 6688 North Central Expressway, Suite 800, Dallas, Texas
75206 (hereinafter referred to individually or collectively as "LICENSOR") and
GTE Mobilnet Service Corp., a New York corporation with offices located at 245
Perimeter Center Parkway, Atlanta, GA 30346 (hereinafter referred to as
"RESELLER").

WHEREAS, LICENSOR provides paging, voice messaging, and related messaging
services (hereinafter referred to as "SERVICES"); and

WHEREAS, RESELLER desires to contract with LICENSOR to resell such SERVICES and,
in connection therewith, to receive blocks of Personal Identification Numbers
(hereinafter referred to as "PINs") and Direct Inward Dialing numbers
(hereinafter referred to as "DIDs") that provide individual access to LICENSOR's
system and SERVICES for resale to members of the general public;

THEREFORE, in consideration of the mutual promises and covenants contained
herein, the parties agree as follows:

1.   TERM

     This Agreement shall be effective on July 1, 1996 and shall continue in
     effect thereafter until October 30, 1996 unless terminated or modified by
     either party in accordance with the provisions of this Agreement.
     Thereafter, this Agreement shall be automatically be renewed for
     consecutive 12 month periods unless terminated by RESELLER by written
     notice to LICENSOR not less than thirty (30) days prior to the expiration
     date. At the end of each twelve (12) month period either party shall have
     the option to review Agreement terms and adjust such terms as are mutually
     agreed upon by the parties.

2.   DEFINITIONS

     (a)  CAP Code - The numeric code that identifies and is unique to each
          pager placed in service on LICENSOR's Paging System

     (b)  DID - A local telephone number assigned by LICENSOR to identify a
          specific pager on the LICENSOR's network. By dialing the DID, the
          respective pager is activated.

     (c)  Equipment - Pagers and related message receiving devices.

     (d)  GTE Tel Ops - GTE Telephone Operations Group.



<PAGE>   5

     (e)  Paging Terminal - A paging central office switch that processes paging
          calls.

     (f)  Paging System - A telecommunications network that provides paging and
          related messaging services throughout a specific geographic area.

     (g)  PIN - Personal Identification Number. A specific number assigned by
          LICENSOR to identify a pager on the LICENSOR's network. By entering
          their PIN into LICENSOR's computer vial a touch-tone telephone, the
          respective pager is activated.

     (h)  Subscriber - A person or entity that is the end user of the LICENSOR's
          Paging System.

     (i)  Telephone Interconnect Charges - Those charges directly associated
          with acquiring direct dial paging telephone numbers from the local
          exchange carrier.

3.   LICENSE

     (a)  LICENSOR grants RESELLER a non-exclusive license to resell LICENSOR's
          SERVICES subject to the rules, regulations and decisions of the
          Federal Communications Commission (hereinafter referred to as "the
          FCC").

     (b)  RESELLER may, upon receipt of LICENSOR's prior written approval, be
          authorized by LICENSOR to license its own sub-agents or affiliates for
          the marketing, promotion and resale of LICENSOR's SERVICES, provided
          that RESELLER shall be responsible for the observance by its
          sub-agents, affiliates, or sub-licensees of the terms and conditions 
          of the Agreement.

4.   INDEPENDENT PARTIES

     Each party is an independent contractor. Except as provided in this
     Agreement, neither party shall have the right, power or authority to act or
     to create any obligation, express or implied, on behalf of the other party.
     All sales by RESELLER shall be in its own name and for its own account

5.   SCOPE

     (a)  This Agreement is non-exclusive and RESELLER is under no obligation to
          LICENSOR to resell any certain amount of SERVICES.

     (b)  LICENSOR hereby agrees to provide SERVICES in an efficient, economic
          and timely fashion in accordance with generally accepted commercial
          and business practices.




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<PAGE>   6

6.   LICENSOR RESPONSIBILITIES

     (a)  LICENSOR shall provide RESELLER's Subscribers with access to its
          Paging System and shall use its good faith efforts to provide
          continuous network service in the geographical locations where
          LICENSOR is legally authorized and has the facilities to provide
          SERVICES.

     (b)  The SERVICES provided by LICENSOR shall include but not be limited to:

          (1)  Numeric display - as long as there is frequency space available,
               unlimited numeric display paging; and

          (2)  Alpha-numeric - as long as there is frequency space available,
               unlimited alpha-numeric paging.

     (c)  LICENSOR shall assign and coordinate all telephone and CAP code
          numbers in order to ensure the compatible initiation of SERVICES to
          Subscribers placed on LICENSOR's Paging System.

7.   RESELLER RESPONSIBILITIES

     (a)  RESELLER shall promote, solicit, market and take all reasonable
          actions, in the exercise of due diligence and good faith, to secure
          Subscribers for LICENSOR's Paging System.

     (b)  RESELLER shall be solely responsible for providing all sales,
          Equipment and customer support services to its Subscribers. RESELLER
          further agrees that all EQUIPMENT provided to its Subscribers shall be
          compatible with the existing transmission system of LICENSOR.

     (c)  RESELLER shall be solely responsible for all billings to and
          collections from its Subscribers, including but not limited to the
          sending of monthly bills, collection of amounts owed or past due, and
          the collection and return of all applicable taxes on such SERVICES or
          Equipment rentals.

     (d)  RESELLER shall provide and mail all announcements or notices required
          to be mailed to its Subscribers as required by any regulatory agency.

     (e)  RESELLER shall assign CAP codes, DIDs and PINs to its Subscribers only
          from the group of CAP codes, DIDs and PINs assigned to RESELLER by
          LICENSOR. RESELLER shall ensure that a given CAP code, DID or PIN is
          not assigned to more that one pager, provided that LICENSOR has not
          given RESELLER duplicate CAP codes, DIDs or PINs, which were then
          assigned in violation of this provision without the fault or knowledge
          of RESELLER.




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<PAGE>   7

         (f)     RESELLER shall maintain and keep in good working order all
                 Equipment leased by RESELLER to its Subscribers pursuant to
                 the terms of this Agreement, in accordance with all
                 manufacturer's specifications and the provisions of the filed
                 tariffs of LICENSOR.

8. PUBLIC REGULATION

         (a)     It is understood that the ultimate control and responsibility
                 for the standard and quality of SERVICES required under the
                 provisions of and license issued by the FCC to LICENSOR shall
                 be retained, rest and remain the prerogative and obligation
                 solely of LICENSOR. No provision of this Agreement shall be
                 construed as vesting in RESELLER any control whatsoever of the
                 radio communication facilities and operations of LICENSOR.

         (b)     This Agreement is subject to all of the terms and conditions
                 of LICENSOR's outstanding authorizations from the FCC and the
                 utility regulatory agencies in the states to which this
                 Agreement pertains, as such tariffs and authorizations are
                 presently in effect or as they may hereafter be revised.
                 Nothing in this Agreement shall be construed so as to impair
                 or diminish LICENSOR's control over the facilities of the
                 applicable stations.

         (c)     This Agreement shall be subject to the approval of the FCC and
                 the local state regulatory agency, if such approval shall be
                 required.

         (d)     This Agreement shall be terminated, amended, revised, or
                 supplemented immediately if required by the FCC or the local
                 state regulatory agency.

         (e)     The imposition by the FCC or local state regulatory agency of
                 any amendments, revisions, deletions or supplements to this
                 Agreement shall thereby relieve LICENSOR and RESELLER of any
                 obligations or liabilities to the other resulting from the
                 provisions of this Agreement which were ordered amended,
                 revised, deleted or supplemented.

9. PRICING

         (a)     RESELLER hereby agrees to pay LICENSOR the charges and fees
                 for SERVICES specified in Exhibit A in accordance with the
                 terms and conditions contained herein.

         (b)     The charges and fees specified in Exhibit A shall commence at
                 the time RESELLER activates each particular number in
                 LICENSOR's Paging System. Such charges shall continue for each
                 number for a minimum of thirty (30) days, and thereafter until
                 the number in questions is canceled





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<PAGE>   8

          or otherwise disconnected in accordance with the provisions herein.
          When a number is activated in the middle of a month, the applicable
          rate will be prorated to the first of the following month so that all
          subsequent bills will be tendered thereafter on a monthly basis.

     (c)  Price decreases arising during the term of this Agreement shall be
          immediately passed on to RESELLER and shall be in effect for all
          current and new Subscriber units.

     (d)  LICENSOR warrants and represents that the prices for SERVICES
          hereunder are no less favorable than those currently extended to any
          other similarly situated National RESELLER of LICENSOR of the same or
          like classification as RESELLER for the same volume/minimum commitment
          levels achieved by RESELLER for the same or like SERVICES.

     (e)  Where allowable by the state regulating authority, the prices charged
          by RESELLER to its Subscribers for all SERVICES shall be determined
          solely by RESELLER. In states where tariff rates are required,
          RESELLER may operate under its own tariff or the tariff of LICENSOR.

10.  BILLING

     LICENSOR shall provide RESELLER with a hard copy statement each month which
     identifies the number of DIDs or PINs billed at the applicable rates. At
     the reasonable request of RESELLER, LICENSOR shall also provide monthly
     billing in an electronic format.

11.  TERMS OF PAYMENT

     Payment shall be due thirty (30) days after the date or the receipt of
     LICENSOR's invoice, whichever is later.

12.  SPECIAL PROGRAMS

     Concurrently herewith, LICENSOR and RESELLER are entering into (i) a
     Representation Agreement, and (ii) a Trial Lease Program substantially in
     the forms attached hereto as Exhibit B and Exhibit C, respectively, and
     incorporated herein for all purposes. The Representation Agreement provides
     for compensation to RESELLER for the promotion of LICENSOR Products and
     SERVICES (as such terms are defined in the Representation Agreement). The
     Trial Lease Program provides for the lease to RESELLER of Products (as
     defined in the Trial Lease Program) from LICENSOR and the subsequent lease
     by RESELLER of such Products to RESELLER's Subscribers.




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<PAGE>   9

13.  PRECEDENCE OF DOCUMENTS

     All orders for SERVICES placed during the term hereof shall be subject to
     and governed by the provisions contained herein. The terms and conditions
     of this Agreement shall control over any conflicting or inconsistent terms
     contained in any order placed with LICENSOR by RESELLER. Notwithstanding
     the foregoing, as to the subject matter there of the terms and conditions
     of the Representation Agreement or Trial Lease Program, as the case may be,
     shall control over any conflicting or inconsistent terms and conditions
     contained in this Agreement.

14.  USE OF CONFIDENTIAL INFORMATION

     (a)  Any specifications, drawings, sketches, models, samples, tools,
          computer programs, technical information, or confidential business
          information or data furnished by the parties to one another hereunder,
          if in writing and clearly marked as "confidential" at the time of
          disclosure, or if oral and designated as confidential at the time of
          disclosure as well as summarized in writing indicating the
          confidential nature of the same within twenty (20) days of disclosure
          (hereinafter called "Confidential Information") shall remain the
          property of the supplier of such Information. All copies so such
          Confidential Information in written, graphic or other tangible form
          shall be returned to the supplier upon request.

     (b)  For the purposes of this Agreement, Confidential Information shall not
          include any information that:

          (1)  was previously known to the recipient;

          (2)  is subsequently received by the recipient free from any
               obligation to keep it confidential;

          (3)  is independently developed by the receiving party; or

          (4)  was or is subsequently made public by the supplier or a third
               party, without breach of any obligation of confidentiality.

     All Confidential Information shall be treated as confidential and not
     disclosed by the recipient, and shall be used by the recipient only in
     connection with fulfilling the obligations of the recipient that arise
     pursuant to this Agreement, unless the prior written consent of the
     supplier is obtained. Confidential Information shall only be distributed to
     those employees who have a need to know.

     (c)  Each party shall treat the other's Confidential Information in
          accordance with a standard of care reasonably calculated to prevent
          inadvertent or




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          accidental disclosure. Nothing herein shall be construed as waiving
          the right of any party to require the other party to execute a
          written non-disclosure agreement, containing reasonable additional 
          terms and conditions, prior to the supplying of particular 
          Confidential Information from time to time.

15.  PUBLICITY

     The parties agree to submit to one another for written approval all
     advertising, sales promotion, press releases and other publicity matters
     relating to the SERVICES furnished or the SERVICES performed by them
     pursuant to this Agreement whereby their respective names or marks are
     mentioned or language from which the connection of said names or marks
     therewith may be inferred or implied, and the parties further agree not to
     publish or use such advertising, sales promotions, press releases, or
     publicity matters without such prior written approval. Such approval shall
     not be unreasonably withheld or delayed by either party.

16.  COMPLIANCE WITH LAWS

     The parties hereto shall comply with the provisions of all applicable
     federal, state, county and local laws, ordinances, regulations and codes
     (including procurement of required permits or certificates) in their
     respective performance hereunder, including, but not limited to, the
     standards promulgated under the Occupational Safety and Health Act,
     Executive Order 11246, as amended, relative to Equal Employment
     Opportunity, Section 503 of the Vocational Rehabilitation Act of 1973, as
     amended, and Section 402 of the Vietnam Era Veterans Readjustment
     Assistance Act of 1974 and all applicable laws, orders and regulations
     concerning immigrants and non-discrimination in the employment of
     minorities, females, veterans and the handicapped. Each party hereby agrees
     to indemnify the other party, and defend the same against, any claims, loss
     or damage sustained because of its noncompliance hereunder.

17.  FORCE MAJEURE

     Neither LICENSOR nor RESELLER shall be responsible for any delay or failure
     in performance of any part of this Agreement to the extent that such
     delay or failure is caused by event beyond its control, which may include,
     but not be limited to, fire, flood, explosion, war strike, embargo,
     government requirement, civil or military authority, and acts of God
     ("Condition(s)"). If any such Condition(s) occurs, the party delayed or
     unable to perform shall promptly give notice to the other party and, if
     such Condition(s) remains at the end of thirty (30) days thereafter, the
     party affected by the other's delay or inability to perform may elect to
     terminate or suspend this Agreement or part thereof, and resume performance
     of this Agreement once the Condition(s) ceases, with an option in




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     the affected party to extend the period of this Agreement up to the length
     of time the Condition(s) endured.

18.  LIABILITY

     (a)  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
          property damage 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.

     (b)  LICENSOR makes no warranty, either express or implied concerning its
          facilities, products, or SERVICES, including, without limitation,
          warranties of merchantability or fitness for a particular purpose.
          RESELLER acknowledges that service interruptions in the
          telecommunications industry frequently are due to circumstances beyond
          a carrier's control and are difficult to assess as to cause or
          resulting damages. The parties agree that LICENSOR shall not be liable
          beyond the actual and direct loss arising out of any mistakes,
          omissions, interruptions, delays, errors, or defects in transmission
          of pages on LICENSOR's Paging System. However LICENSOR's liability
          shall in no event exceed an amount equivalent to the proportionate
          charge to RESELLER for the period of the disruption of SERVICES or the
          amount of five hundred dollars ($500), whichever is less. LICENSOR
          shall not be liable for any act or omission of any other entity
          furnishing SERVICES to RESELLER. Neither party shall be liable for any
          special, incidental or other consequential damage or losses, including
          without limitation lost profits, or for loss of stored, transmitted or
          recorded data, even if it has been advised of the possibility of such
          damages, nor shall either party be liable for any such damages due to
          the fault or negligence of the other party or its employees, agents,
          or representatives.

     (c)  All work performed under this Agreement by any party shall be
          performed as an independent contractor and not as an agent of any
          other party. Persons furnished by the respective parties shall be
          solely the employees or agents of such parties, respectively, and
          shall be under the sole and exclusive direction of such parties. They
          shall not be considered employees of the other party for any purpose.
          Each party shall be




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                 responsible for compliance with all laws, rules and
                 regulations involving their respective employees or agents,
                 including (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, respectively,
                 for payment of taxes, including federal, state, and municipal
                 taxes, chargeable or assessed with respect to its employees or
                 agents, such as social security, unemployment, workers'
                 compensation, disability insurance and federal and state
                 income tax withholding.

         (d)     RESELLER and LICENSOR each agree to maintain during the term
                 hereof all insurance and/or bonds required by law or this
                 Agreement, including, but limited to (1) Workers' Compensation
                 and related insurance as prescribed by applicable law; (2)
                 employer's liability insurance with limits of at least $100,000
                 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 $500,000 for
                 combined single limit for bodily injury, including death,
                 and/or property damage. RESELLER and LICENSOR each shall cause
                 the other to be included as an Additional Insured under their
                 respective policies and RESELLER's and LICENSOR's appropriate
                 coverage under such policies shall be primary. RESELLER and
                 LICENSOR 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 advanced written notice is
                 given to the party named as an Additional Insured.
                 Notwithstanding the above, LICENSOR and RESELLER shall each
                 have the option, where permitted by law, to self-insure any or
                 all of the foregoing risks.

19.      ASSIGNMENT

         (a)     Except as otherwise provided herein, the rights and
                 obligations of the parties hereunder shall neither be assigned
                 nor delegated without prior written consent of the other
                 party, provided that any party may assign or delegate their
                 respective rights and obligations hereunder, in whole or in
                 part, to any parent, subsidiary or affiliate of RESELLER or
                 LICENSOR that was such a parent, subsidiary or affiliate at
                 the time of execution of this Agreement upon prior written
                 notice to the other. Such assignment shall not diminish any
                 rights or duties that LICENSOR or RESELLER may have had prior
                 to the effective date of assignment.

         (b)     The limitation on assignment does not apply to an assignment
                 confined solely to monies due or to become due under this
                 Agreement, provided RESELLER or LICENSOR is given thirty (30)
                 days prior written notice of such assignment. An assignment of
                 monies shall be void to the extent





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<PAGE>   13
          that it attempts to impose upon RESELLER or LICENSOR obligations to
          the assignee in addition to the payment of such monies, or to preclude
          RESELLER or LICENSOR from dealing solely and directly with the other
          in all matters pertaining hereto, including negotiation of amendments
          or settlement of amounts due. If RESELLER or LICENSOR makes such an
          assignment, it is and shall remain responsible for payment hereunder.

20.  TAXES

     RESELLER shall be liable for and shall reimburse LICENSOR for actual
     payments of any Retailers' Excise Taxes, state and local sales and use
     taxes, or any similar taxes as applicable, with respect to transactions
     under this Agreement. Taxes payable by RESELLER shall be separately stated
     in LICENSOR'S invoices and shall not be included in LICENSOR's prices.
     RESELLER shall not be liable for any tax for which a valid exemption
     certificate acceptable to the applicable state or local taxing authorities
     is furnished by RESELLER to LICENSOR.

21.  RECORDS

     (a)  LICENSOR shall maintain complete and accurate records of all amounts
          billable to and payments made by RESELLER hereunder, in accordance
          with generally accepted accounting practices. LICENSOR shall retain
          such records for a period of three (3) years from the date of
          rendering of SERVICES covered by this Agreement. LICENSOR agrees to
          provide supporting documentation concerning any disputed amount of
          invoice to RESELLER within thirty (30) days after RESELLER provides
          written notification of the dispute to LICENSOR. LICENSOR shall retain
          such records for three (3) years from date of invoice.

     (b)  RESELLER's original Subscriber records shall be and remain the
          property of RESELLER. LICENSOR shall be entitled at LICENSOR's expense
          during normal business hours to make copies of such records directly
          relating to information verifying the number of Subscribers or
          compliance by RESELLER to the terms of this Agreement.

22.  RIGHT OF ACCESS

     LICENSOR and RESELLER shall each permit reasonable access during normal
     working hours to its facilities in connection with work hereunder. No
     charge shall be made for such visits. It is agreed that reasonable prior
     notification shall be given when access is required.



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<PAGE>   14

23.  TERMINATION

     (a)  RESELLER may terminate this Agreement without cause, effective
          immediately, upon written notice to LICENSOR in the event RESELLER's
          resale activities are combined with the resale activities of GTE Tel
          Ops under the Resale Agreement between GTE Tel Ops and LICENSOR dated
          November 1, 1993 (Resale Combination). In the event of a Resale
          Combination, all of RESELLER's subscribers will be transferred to the
          account of GTE Tel Ops and the terms and conditions provided in the
          Resale Agreement dated November 1, 1993 shall thereafter govern.
          Termination shall not affect any order placed prior to the date of
          termination.

     (b)  Either party may terminate this Agreement, effective immediately,
          without liability for said termination, upon written notice to the
          other party, if any of the following events occur:

          (1)  The other files a voluntary petition in bankruptcy;

          (2)  The other is adjudged bankrupt;

          (3)  A court assumes jurisdiction of the assets of the other under a
               federal reorganization act;

          (4)  A trustee or receiver is appointed by a court for all or a
               substantial portion of the assets of the other;

          (5)  The other becomes insolvent or suspends its business;

          (6)  The other makes and assignment of its assets for the benefits of
               its creditors, except as required in the ordinary course of
               business;

          (7)  The identity of the other's business is materially changed by
               sale of its business, transfer of control of its outstanding
               stock, merger or otherwise.

     (c)  Either party may immediately terminate this Agreement for a material
          breach or default of any of the terms, conditions or covenants of this
          Agreement by the other, provided that such termination may be made
          only following the expiration of a thirty (30) day period during which
          the other party has failed to cure such breach after having been given
          written notice of such breach.

     (d)  In the event of a material breach of default by LICENSOR, provided
          that LICENSOR has failed to cure the same within thirty (30) days of
          its




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<PAGE>   15

          receipt of RESELLER's written notice of default, or if said default
          cannot be cured within a thirty (30) day period,' LICENSOR has failed
          to commence and diligently pursue curing such a default, RESELLER
          shall be under no obligation to continue to provide LICENSOR's
          SERVICES to its Subscribers, and RESELLER shall have the right to
          assign those Subscribers to another paging service.

24.  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 shall 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 non-lawyer,
          business representatives. The 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 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 (1) individual of another




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          party. Additional discovery may be permitted upon mutual agreement
          of the parties. The arbitration hearing shall be commenced with sixty
          (60) days of the demand for arbitration and the arbitration shall be
          held in Dallas, Texas. 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 cost of these procedures. A party
          seeking discovery shall reimburse the responding party the cost of
          production of the documents (to include search time and reproduction
          time costs). The parties shall equally share the fees of the
          arbitration and the arbitrator.

25.  NOTICES

     Any notice or demand given under the terms of this Agreement or pursuant to
     statute shall be in writing and shall be given or made by telegram,
     facsimile transmission, certified or registered mail, express mail or other
     overnight delivery service or hand delivery, proper postage or other
     charges paid and addressed or directed to the respective parties as
     follows:



                                  To RESELLER:

     GTE Mobilnet Corp. 
     245 Perimeter Center Parkway 
     Atlanta, GA 30346 
     Attention: Director-Vertical Services

                                  To LICENSOR:

     PageMart
     6688 North Central Expressway
     Suite 800
     Dallas, Texas 75206
     Attention: Vice President-Division General Manager

     Such notice or demand shall be deemed to have been given or made when
     actually received or seventy-two (72) hours after being sent, whichever
     occurs first.




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<PAGE>   17

     The address for notice set out above may be changed at any time by giving
     thirty (30) days prior written notice in the manner above.

26.  NONWAIVER

     Either party's failure to enforce any of the provisions of this Agreement
     and/or any purchase order, or to exercise any option hereunder, shall in no
     way construed as a waiver of such provisions, rights, or options, or in any
     way be deemed to affect the validity of this Agreement or any purchase
     order.

27.  SEVERABILITY

     Should any part of this Agreement for any reason be declared invalid by
     order of any court or regulatory agency, such order shall not affect the
     validity of any remaining portion, which shall remain in force and effect
     as if this Agreement had been executed with the invalid portion eliminated,
     and it is hereby declared the intention of the parties that they would have
     executed the remain portion of this Agreement without including therein any
     such part or portion which may, for any reason be hereafter declared
     invalid.

28.  SECTION HEADINGS

     The headings of the sections herein are inserted for convenience only and
     are not intended to affect the meaning or interpretation of this Agreement.

29.  SURVIVAL OF OBLIGATIONS

     The respective obligations of LICENSOR and RESELLER under this Agreement
     which by their nature would continue beyond the termination, cancellation
     or expiration hereof, shall survive termination, cancellation or expiration
     hereof.

30.  CHOICE OF LAW

     The construction, interpretation and performance of this Agreement shall be
     governed by and construed in accordance with the domestic laws of the state
     of Delaware.

31.  ENTIRE AGREEMENT

     This Agreement and the exhibits hereto constitute the entire agreement
     between LICENSOR and RESELLER. No modifications shall be made this
     Agreement unless in writing and signed by appropriate representatives of
     the parties.




                                       14
<PAGE>   18

IN WITNESS WHEREOF, the parties hereto have executed this Agreement through
their authorized corporate representatives.

PAGEMART, INC.                          GTE MOBILNET SERVICE CORP.




By: /s/ DOUG GLEN                       By: /s/ TERRY LEWIS
   -------------------------               ------------------------------------

Name:  Doug Glen                        Name:  Terry Lewis

Title: Vice President,                  Title: Vice President, 
       Strategic Alliances                     Product Management


                            Attested By: /s/ M.C. HOPPE
                                        ---------------------------------------
                                        Name:  M. C. Hoppe
                                             ----------------------------------
                                               Vice President
                                        Title: Finance & Information Management
                                             ----------------------------------




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