<PAGE>   1

                                                                   EXHIBIT 10.21


                                                  Agreement Number: C989107SC001



                                RESALE AGREEMENT

                                     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.       TERM.....................................................................................................1
2.       DEFINITIONS..............................................................................................1
3.       LICENSE..................................................................................................3
4.       INDEPENDENT PARTIES......................................................................................3
5.       SCOPE....................................................................................................4
6.       LICENSOR RESPONSIBILITIES................................................................................4
7.       RESELLER RESPONSIBILITIES................................................................................4
8.       LIQUIDATED DAMAGES.......................................................................................6
9.       PUBLIC REGULATION........................................................................................6
10.      PRICING..................................................................................................7
11.      AUTHORIZED EQUIPMENT.....................................................................................8
12.      BILLING/TERMS OF PAYMENT.................................................................................9
13.      PRECEDENCE OF DOCUMENTS..................................................................................9
14.      USE OF CONFIDENTIAL INFORMATION..........................................................................9
15.      PUBLICITY...............................................................................................11
16.      TRADEMARKS AND TRADE NAMES..............................................................................12
17.      COMPLIANCE WITH LAWS....................................................................................12
18.      FORCE MAJEURE...........................................................................................12
19.      CENTURY COMPLIANCE......................................................................................12
20.      INDEMNIFICATION.........................................................................................13
21.      WARRANTY................................................................................................15
22.      INFRINGEMENT............................................................................................16
23.      PERMITS.................................................................................................17
24.      ASSIGNMENT..............................................................................................17
25.      TAXES...................................................................................................18
26.      RECORDS.................................................................................................18
27.      RIGHT OF ACCESS.........................................................................................18
28.      TERMINATION.............................................................................................18
29.      DISPUTE RESOLUTION......................................................................................20
30.      NOTICES.................................................................................................21
31.      NONWAIVER...............................................................................................22
32.      SEVERABILITY............................................................................................22
33.      SECTION HEADINGS........................................................................................22
34.      SURVIVAL OF OBLIGATIONS.................................................................................22
35.      CHOICE OF LAW...........................................................................................22
36.      ENTIRE AGREEMENT........................................................................................23
37.      SIGNATURES..............................................................................................23
</TABLE>

<TABLE>

<S>                                               <C>    
         EXHIBIT A-Affiliates                     Exhibit E-Reseller National Account Service Commitment 
         EXHIBIT B-Service Level Agreement        Exhibit F-Technical Standards 
         EXHIBIT C-Pricing
         EXHIBIT D-Authorized Equipment                        
</TABLE>



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                                RESALE AGREEMENT

This Resale Agreement (this "Agreement") is made and entered into effective as
of September 1, 1998, 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 75219-5111 (hereinafter referred to as
"LICENSOR") and GTE Communication Systems Corporation, acting through its GTE
Supply division, for the benefit of itself and the affiliated companies listed
in Exhibit A ("Affiliates"), which may be modified from time to time by
RESELLER, with offices at 700 Hidden Ridge, Irving, Texas 75038 (hereinafter
referred to as "RESELLER").

WHEREAS, LICENSOR provides paging and wireless messaging services, voice
messaging services, and customer support services (the "Services"); and

WHEREAS, RESELLER desires to contract with LICENSOR to resell the Services in
accordance with Exhibit B, Service Level Agreement and, in connection therewith,
to receive blocks of PINS, Capcodes and DIDs (each as defined below).

WHEREAS, RESELLER desires to contract with LICENSOR to resell such Services and,
in connection therewith, to receive access ports and codes to LICENSOR's paging,
administrative and data systems.

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

1.       TERM

         This Agreement shall be effective on September 1, 1998 and shall
         continue in effect thereafter until August 31, 2001, unless terminated
         or modified in accordance with the provisions of this Agreement. This
         Agreement shall be automatically terminated unless renewed by RESELLER
         by written notice to LICENSOR not less than thirty (30) days prior to
         the expiration date. RESELLER may unilaterally renew this Agreement for
         additional periods of three years by providing LICENSOR with written
         notice not less than thirty (30) days prior to the expiration date of
         this or a succeeding contract term. This Agreement supersedes Agreement
         999999-93-12 dated November 1, 1993 and as amended but will not
         supersede any current Agreement with any other Affiliate.

2.       DEFINITIONS

         a.       Staffed Coverage - Coverage of any help desk or other service
                  which is staffed by a LICENSOR employed live-person for
                  real-time interaction with RESELLER.

         b.       DID - A local telephone number assigned by RESELLER or
                  LICENSOR to identify a specific pager on the LICENSOR's
                  network. By dialing the DID, the telephone network will switch
                  the call to a LICENSOR owned terminal, and the terminal will
                  associate the specific number with a specific pager/paging
                  device on the LICENSOR's network.

         c.       Equipment - Pagers and related message receiving devices.

         


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         d.       Interconnections - Any and all devices, services,
                  circuits, systems, or related items

                  which connect any of the LICENSOR's various systems
                  (including, but not limited to; Paging Systems, Administrative
                  Systems, And Activation Systems).

         e.       Modification - Any addition, deletion, or reconfiguration to
                  any and/or all hardware and/or software associated with any
                  networks, network nodes, system, or system nodes.

         f.       Network Node And/or System Node - Any portion or individual
                  piece of any network or system which is intended to perform a
                  function which allows the network or system to fulfill its
                  intended function.

         g.       Non-functional - Not performing the function intended by
                  manufacturer, LICENSOR design, or portrayed to RESELLER via
                  coverage maps and/or other LICENSOR provided information.

         h.       Subscriber - A person or entity whose account is owned by the
                  RESELLER and whose services are provided by use of all or part
                  of the LICENSOR's Paging System.

         i.       Upgrade - Any addition of hardware or software which is
                  intended to improve or modify the performance of any network,
                  network node, system, or system node.

         j.       System Upgrade - Any addition of hardware or software which is
                  intended to improve or modify the performance of any system or
                  system node.

         k.       TNPP - Telocator Network Paging Protocol.

         l.       Calls - When discussing Pricing, Calls refers to the number of
                  telephone calls or pages a single account is allotted in any
                  given month. For the purpose of pricing LICENSOR's Services,
                  Calls will be aggregated as defined elsewhere in this
                  contract. When discussing DID or TAP interconnections to
                  LICENSOR's network, Calls refers to a telephone call into
                  LICENSOR's network.

         m.       Capcode - An alphanumeric/numeric number which is assigned to
                  one and only one paging device on any given frequency. This
                  number is, in effect, the paging devices address, and
                  therefore must be unique to each paging device. CAPCODES are
                  defined, developed, and controlled by the LICENSOR.

         n.       Latency - Any delay.

         o.       Coverage zone - Any area which has radio frequency coverage on
                  any LICENSOR owned frequency, with a minimum signal level of
                  -88db. as of the date of execution of this Agreement.

         p.       Root Cause Analysis - A report detailing the cause and effect
                  of a specific network deficiency. This report should identify,
                  at a minimum and in a reasonable amount of detail, the who,
                  what, when, where, why, and effect of any network deficiency.

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         q.       PIN - Personal Identification Number. A specific number
                  assigned by LICENSOR to identify a pager on the LICENSOR's
                  Network. By entering the PIN into LICENSOR's computer via a
                  touch-tone telephone or other devices, the respective pager is
                  activated.

         r.       On-call - When a LICENSOR employee can be contacted via pager,
                  cellular phone, or regular phone service and is available for
                  real-time interaction within a specified time frame.

         s.       Pending - Time of delay during which incoming calls are
                  rejected or blocked, or account activations, Modifications, or
                  deletions are not processed by any network, system, network
                  node, or system node.

         t.       Consumer Price Index - where identified within this Agreement
                  shall mean the CPI- U, U.S.City Average for all items, with
                  the index base period set as (1982-84=100).

3.       LICENSE

         a.       LICENSOR grants RESELLER a non-exclusive license to resell
                  LICENSOR's Services subject to the terms and conditions of
                  this Agreement, applicable law, and the rules, regulations and
                  decisions of the Federal Communications Commission or any
                  other applicable regulatory body.

         b.       RESELLER may license its own sub-agents, affiliates, or any
                  parent, subsidiary or affiliate of any third party with the
                  public intention of merging, acquiring or otherwise
                  affiliating itself with RESELLER announced before or at the
                  time of execution of this Agreement for the marketing,
                  promotion and resale of LICENSOR's Services, provided that
                  RESELLER shall provide sixty (60) days notice to LICENSOR of
                  all sub-agents and affiliates authorized by RESELLER for
                  promotion and resale on its behalf. RESELLER shall ensure that
                  its sub-agents, affiliates, or sub-licensees abide by the
                  terms and conditions of this Agreement.

4.       INDEPENDENT PARTIES

         In providing any Services or reselling any Services pursuant to this
         Agreement, each party is acting solely as an independent contractor and
         not as an agent of the other party. Each party shall be responsible for
         compliance with all laws, rules and regulations involving its
         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, worker's
         compensation, disability insurance and federal and state income tax
         withholding. Neither party undertakes by this Agreement or otherwise to
         perform or discharge any liability or obligation of the other party,
         whether regulatory or contractual, or to assume any responsibility
         whatsoever for the conduct of the business or operations of the other
         party. Nothing contained in this Agreement 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. Except as provided in this Agreement, neither party shall
         have the right, power, or authority to act or to create any 

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         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, and all relevant
                  sections of this contract.

6.       LICENSOR RESPONSIBILITIES

         a.       LICENSOR shall provide RESELLER's Subscribers with access to
                  its Paging System and shall provide continuous (when
                  commercially feasible) network service in the geographical
                  locations where LICENSOR is legally authorized to provide
                  Services in accordance with all relevant sections of this
                  Agreement, including all Exhibits attached hereto.

         b.       The Services provided by LICENSOR shall include but not be
                  limited to:

                  i.       Numeric display - Numeric display paging. LICENSOR
                           guarantees RESELLER the use of a minimum enough
                           bandwidth/frequency space to support a net growth
                           rate of [*] percent per year above the previous
                           year's base as of the previous December 31; and

     ii.      Alphanumeric - Alphanumeric paging. LICENSOR guarantees RESELLER
              the use of a minimum FLEX bandwidth/frequency space to support a
              net growth rate of [*] percent per year for Local Alphanumeric
              Paging above the previous year's base. LICENSOR guarantees
              RESELLER the use of a minimum FLEX or REFLEX bandwidth/frequency
              space to support a net growth rate of [*] percent per year for
              State, and Regional, and Nationwide Alphanumeric Paging above the
              previous year's base as of the previous December 31.
                                                  
         c.       LICENSOR shall assign and coordinate all telephone and Capcode
                  numbers in order to ensure the initiation of service and to
                  ensure ongoing service to Subscribers placed on LICENSOR's
                  Paging System in accordance with Exhibit B.

7.       RESELLER RESPONSIBILITIES

         a.       RESELLER shall use commercially reasonable efforts to promote,
                  solicit, market the Services.

         b.       RESELLER shall be solely responsible for providing all sales,
                  equipment and customer support services to its Subscribers.

         c.       Upon LICENSOR's reasonable request, RESELLER shall provide
                  non-binding sales forecasts by quarter for the following year.

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                                        4


*  CONFIDENTIAL INFORMATION HAS BEEN DELETED. THE OMITTED MATERIAL HAS BEEN 
   FILED SEPARATELY WITH THE COMMISSION PURSUANT TO AN APPLICATION FOR 
   CONFIDENTIAL TREATMENT.

<PAGE>   7




         d.       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 service or equipment rentals.

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

         f.       RESELLER shall assign Capcode, DID's, and PIN's to its
                  Subscribers only from the group of Capcodes, DID's and PIN's
                  assigned to RESELLER by LICENSOR. RESELLER shall ensure that a
                  given Capcode, DID or PIN is not assigned to more than one
                  pager, provided that LICENSOR has not given RESELLER duplicate
                  Capcodes, DID's or PIN's, which were then assigned in
                  violation of this provision without the fault or knowledge of
                  RESELLER. Under Transmission Only Paging Services and/or
                  Quasi-RESELLER Paging Services as described below, RESELLER
                  will provide the DID numbers, and LICENSOR will provide the
                  Capcodes and PIN NUMBERS to RESELLER. LICENSOR will provide
                  quantities of Capcodes and PINS to RESELLER as necessary to
                  support RESELLER's on-going sales efforts and existing
                  subscriber base.

                  i.       Under Full RESELLER Paging Services the RESELLER will
                           procure customers which will be activated on one of
                           LICENSOR's paging terminals and in LICENSOR's billing
                           system via PRIME, Vantive, WinFast, ActFast,
                           Dial-Now, or other LICENSOR provided activation
                           systems. LICENSOR will provide the pager number and
                           all in-bound calling. When a valid customer receives
                           a page the in-bound call is accepted by LICENSOR (at
                           the terminal), the customer is validated in the
                           terminal, and the page is transmitted to the
                           transmitters in the correct coverage zone via
                           satellite simulcast. The transmitters then send the
                           page out via one of LICENSOR's frequencies (that
                           frequency which matches the receiver in that specific
                           customer's pager). Multiple sub-services are to be
                           provided by LICENSOR to RESELLER under this service
                           as defined below.

                  ii.      Under Quasi-RESELLER Paging Services the RESELLER
                           will procure customers which will be activated on a
                           RESELLER paging terminal, one of LICENSOR's paging
                           terminals, and LICENSOR's billing system via PRIME,
                           Vantive, WinFast, ActFast, Dial-Now, or other
                           LICENSOR provided activation systems. When a valid
                           customer receives a page the in-bound call is
                           accepted by RESELLER (at the terminal), the customer
                           is validated in the terminal, and the page is
                           transmitted to a LICENSOR terminal via TNPP. The data
                           is directed by LICENSOR's terminal to the
                           transmitters in the correct coverage zone via
                           satellite simulcast. The transmitters then send the
                           page out via one of LICENSOR's frequencies (that
                           frequency which matches the receiver in that specific
                           customer's pager). Multiple sub-services are to be
                           provided by LICENSOR to RESELLER under this service
                           as defined below.


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                  iii.     Under Transmission Only Paging Services the RESELLER
                           will procure customers which will be activated on a
                           RESELLER paging terminal via a RESELLER provided
                           activation system. Billing will be based on the
                           amount of data that passes through the LICENSOR's
                           system as defined in the pricing section of this
                           contract. When a valid customer receives a page the
                           in-bound call is accepted by RESELLER (at the
                           RESELLER owned terminal), the customer is validated
                           in the terminal, and the page is transmitted to a
                           LICENSOR terminal via TNPP. The data is directed by
                           LICENSOR's terminal to the transmitters in the
                           correct coverage zone via satellite simulcast. The
                           transmitters then send the page out via one of
                           LICENSOR's frequencies (that frequency which matches
                           the receiver in that specific customer's pager).
                           Multiple sub-services are to be provided by LICENSOR
                           to RESELLER under this service as defined below.

         g.       RESELLER, in accordance with all manufacturer's
                  specifications, shall maintain and keep in good working order
                  all equipment leased by RESELLER to its Subscribers pursuant
                  to the terms of this Agreement.

8.       LIQUIDATED DAMAGES

         The parties recognize the RESELLER will suffer substantial economic
         loss should LICENSOR fail to meet various performance criteria set
         forth in this Agreement and all exhibits attached hereto. Because such
         loss is often difficult to quantify in particular instances, the
         parties have agreed that LICENSOR will pay to RESELLER certain sums
         (pursuant to various described formulae) characterized herein as
         liquidated damages in the event of LICENSOR's failure to meet agreed
         performance criteria. These liquidated damages are not penalties, but
         rather are the parties good faith estimation of RESELLER's damages
         caused by LICENSOR's failure to meet such performance criteria.

9.       PUBLIC REGULATION

         a.       It is understood that the ultimate control and responsibility
                  for the standard and quality of Services required under the
                  provisions of any 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
                  licenses, radio communication facilities, or 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
                  any regulatory agency, if such approval shall be required.

         d.       This Agreement shall be terminated, amended, revised, or
                  supplemented 



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                  immediately if required by the FCC or any state regulatory
                  agency.

         e.       The imposition by the FCC or any 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.

10.      PRICING

         a.       RESELLER hereby agrees to pay LICENSOR the charges and fees
                  for Services as specified in Exhibit C, Pricing and in
                  accordance with the terms and conditions contained herein.

         b.       The charges and fees specified in Exhibit C 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 question is canceled 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.       The specified prices in Exhibit C shall remain firm for the
                  first twenty-four (24) months of this Agreement. After the
                  twenty-fourth (24th) month from the execution of this
                  agreement, LICENSOR is not obligated to, but may, increase
                  prices once in each twelve (12) month period by giving written
                  notice to RESELLER at least ninety (90) days prior to the
                  proposed effective date of the new pricing. LICENSOR shall not
                  increase the prices in Exhibit C by more than the lesser of
                  the Consumer Price Index, as defined within this Agreement, or
                  * in any twelve (12) month period.

         d.       Effect of Change in Law or Regulation. Notwithstanding
                  anything to the contrary contained in the Agreement or any
                  schedule or exhibit attached hereto, LICENSOR shall have the
                  right to change the fees changed for Services or change the
                  Services at any time upon thirty (30) days prior notice to
                  RESELLER to the extent that such change is necessary to comply
                  with applicable law or regulation, whether state or federal,
                  or to the extent that a change in applicable law or regulation
                  substantially affects LICENSOR's operating costs. LICENSOR
                  shall provide detailed documentation substantiating the change
                  in operating costs RESELLER must approve any changes in the
                  Service fees or the Services in writing prior to any changes
                  in the Service fees or the Services, which approval will not
                  be unreasonably withheld. If RESELLER and LICENSOR cannot
                  mutually agree on the extent/effect of these changes on
                  LICENSOR's operating costs, then the parties agree to utilize
                  Section 29, DISPUTE RESOLUTION to resolve the issue.

         e.       LICENSOR warrants and represents that the prices for Services
                  hereunder are no less favorable than those currently extended
                  to any other similarly situated RESELLER of LICENSOR of the
                  same or like classification as RESELLER for the same volume
                  achieved by RESELLER for the same or like Services.

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*  CONFIDENTIAL INFORMATION HAS BEEN DELETED. THE OMITTED MATERIAL HAS BEEN 
   FILED SEPARATELY WITH THE COMMISSION PURSUANT TO AN APPLICATION FOR 
   CONFIDENTIAL TREATMENT.

<PAGE>   10


         f.       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.

11.      AUTHORIZED EQUIPMENT

         a.       RESELLER and its Subscribers shall only activate and utilize
                  the equipment which is either listed in Exhibit D, AUTHORIZED
                  EQUIPMENT or complies with all technical standards as defined
                  in Exhibit F in connection with LICENSOR's Services, however,
                  unless equipment is listed on Exhibit D, LICENSOR will not
                  provide troubleshooting support for equipment problems and
                  LICENSOR will not be responsible for meeting the SLA
                  requirements in Exhibit B, Section 2.4. LICENSOR may revise
                  Exhibit D from time to time upon delivery of written notice to
                  RESELLER at least one hundred twenty (120) days prior to the
                  effective date of such revision. If LICENSOR amends Exhibit D
                  in such a manner whereby previously authorized equipment is no
                  longer authorized for use on LICENSOR's Paging System,
                  LICENSOR agrees to continue to provide service to such
                  previously authorized equipment receiving Services as of the
                  date of the notice for one (1) year after the date of such
                  notice.

         b.       If LICENSOR modifies LICENSOR's network in any manner after
                  the date of execution of this Agreement whereas any previously
                  authorized equipment sold by RESELLER to RESELLER's customers
                  no longer functions either; (i) as a unit, or (ii) in
                  conjunction with the Network (i.e. garbled messages or
                  consistent garbled messages), then LICENSOR will bear the
                  expense to provide substitute authorized equipment in exchange
                  for the previously authorized equipment then utilized by
                  RESELLER's Subscribers. All pagers previously sold by LICENSOR
                  to RESELLER are included in this Agreement, as they are still
                  functionally operational on this network. Nothing in this
                  section shall be construed such that LICENSOR is responsible
                  for end user devices which are malfunctioning as an individual
                  device (i.e. the problem is specific to a specific individual
                  pager, and not inherent in substantially all devices of both
                  the same manufacturer and model).

         c.       LICENSOR's liability will not exceed the net book value of the
                  equipment based on a five (5) year straight line depreciation
                  schedule from the date of purchase from manufacturer or other
                  supplier.

         d.       LICENSOR is not liable for equipment which has been recalled
                  by manufacturer and for which manufacturer either repairs or
                  replaces. However, nothing in this section should be construed
                  to limit LICENSOR's responsibility to thoroughly test all
                  equipment for compatibility with LICENSOR's network prior to
                  approving the equipment for inclusion in Exhibit D.

         e.       LICENSOR will provide commercially reasonable technical
                  standards for new equipment within thirty (30) days after the
                  signing of this Agreement, or RESELLER will have the right to
                  develop commercially reasonable standards at RESELLER's sole
                  discretion. These standards will be included as an automatic
                  amendment to this contract as Exhibit F. Any equipment which
                  is developed by or on behalf of RESELLER must meet these
                  commercially reasonable technical standards in order 



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                  for RESELLER to utilize the equipment on LICENSOR's network.
                  However, LICENSOR reserves the right to thoroughly test all
                  new equipment for technical compatibility with the network. If
                  LICENSOR determines that the new equipment is not technically
                  compatible with the network, regardless of whether or not the
                  equipment meets the technical standards, LICENSOR agrees that
                  RESELLER may utilize the equipment on LICENSOR's network, and
                  RESELLER agrees that the equipment will not be added to
                  Exhibit D, Authorized Equipment, provided however, that
                  LICENSOR provides detailed analysis of the technical
                  incompatibility, thus providing RESELLER with the opportunity
                  to correct any such technical incompatibility. Once any such
                  technical incompatibilities are corrected, RESELLER may
                  resubmit the new equipment for testing for technical
                  compatibility with the network and, subsequently, inclusion in
                  Exhibit D upon acceptance, which acceptance shall not be
                  unreasonably withheld.

12.      BILLING/TERMS OF PAYMENT

         a.       LICENSOR shall provide RESELLER monthly billing in accordance
                  with Exhibit B, Service Level Agreement, Section 4,
                  Billing/Invoicing Services.

         b.       Payment for Services shall be due thirty (30) days from the
                  date of receipt of an undisputed invoice, unless payment terms
                  more favorable to RESELLER are stated on LICENSOR's invoice
                  and RESELLER elects to pay on such terms. RESELLER will remit
                  payment to LICENSOR only for the amounts not disputed in good
                  faith by RESELLER. If a disputed amount is going to be with
                  held from a current invoice, RESELLER will notify LICENSOR,
                  giving reasons for the dispute prior to payment due date.
                  RESELLER shall retain the right to dispute any invoice amount
                  (paid or unpaid) within ninety (90) days after the date of
                  receipt. If RESELLER fails to make timely payment on any
                  monthly undisputed invoice amount, RESELLER will pay LICENSOR
                  interest from the date due at the rate of one and one half (1
                  1/2%) percent per month or the maximum rate allowed by law,
                  whichever is lower.

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 written Agreement shall control over any conflicting
         or inconsistent terms and conditions contained in any order placed with
         LICENSOR by RESELLER.

14.      USE OF CONFIDENTIAL INFORMATION

         a.       In order for the parties to perform their respective
                  obligations under this Agreement, it may be necessary for
                  either party to disclose to the other technical, personnel
                  and/or business information in written, graphic, electronic,
                  oral or other tangible or intangible forms including, but not
                  limited to, specifications, records, data, computer programs,
                  drawings, schematics, know-how, notes, models, reports and
                  samples. Such information may contain proprietary or
                  confidential material, or material subject to applicable laws
                  regarding secrecy of communications or trade secrets
                  (Confidential Information).


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<PAGE>   12



         b.       Each party acknowledges and agrees:

                  i.       That all Confidential Information acquired by either
                           party from the other shall be and shall remain the
                           exclusive property of the disclosing party;

                  ii.      To identify in writing as confidential or
                           proprietary, or mark as confidential or proprietary,
                           any information that either party deems to be
                           Confidential Information;

                  iii.     That information that is disclosed orally shall not
                           be considered Confidential Information unless it is
                           reduced to writing or to a written summary that
                           identifies the orally-disclosed topics to be
                           considered as Confidential Information and such
                           writing is provided to the recipient at the time of
                           disclosure or within thirty (30) days thereafter;


                  iv.      To receive in confidence any Confidential
                           Information; to limit access to such Confidential
                           Information to authorized employees, agents and
                           contractors (covered by obligations at least as
                           restrictive as those set forth in this Section) who
                           have a need to know the Confidential Information in
                           order for the party to perform its obligations under
                           this Agreement and who have been informed of the
                           confidential and proprietary nature; not to disclose,
                           reveal or divulge any Confidential Information or
                           authorize any other person to do so except: (1) as
                           specifically approved in writing by the disclosing
                           party, or; (2) as required in connection with the due
                           and proper performance by the receiving party of its
                           obligations under this Agreement. (which shall not be
                           deemed to include disclosure to consultants, advisors
                           or other third parties which are not full-time,
                           regular employees of the receiving party. However,
                           disclosure may be made to consultants, advisors, or
                           other contractors which have a need to know and which
                           are bound by confidentiality agreements no less
                           stringent than this Agreement);

                  v.       To use such Confidential Information only for the
                           purposes of performing their obligations under this
                           Agreement and for such other purposes as may be
                           agreed upon between the parties in writing;

                  vi.      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: (1) notify the
                           disclosing party of the existence and terms of such
                           request or advice, (2) 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 (3) if disclosure is
                           required, cooperate with the disclosing party in
                           taking legally available steps 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;



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<PAGE>   13


                  vii.     Upon request of the disclosing party, to return all
                           Confidential Information to such party, or to destroy
                           any documents, computer media or records, in written,
                           graphic, or other tangible form, that contain any
                           Confidential Information;

                  viii.    That the obligations with respect to Confidential
                           Information shall extend for a period of five (5)
                           years beyond completion of the term of this
                           Agreement.

                  ix.      That nothing contained in this Section shall be
                           construed as a license or permission to make, use, or
                           sell the Confidential Information or Services derived
                           therefrom.

         c.       The obligations contained in this Section do not apply to
                  Confidential Information that:



                  i.       As shown by reasonably documented proof, was in the
                           receiving party's possession prior to receipt thereof
                           from the disclosing party;

                  ii.      As shown by reasonably documented proof, was received
                           by one party in good faith from a third party not
                           subject to a confidential obligation to the other
                           party;

                  iii.     Now is or later becomes publicly known through no
                           breach of confidential obligation by the receiving
                           party;

                  iv.      Is disclosed pursuant to a requirement imposed by a
                           governmental agency or is otherwise required to be
                           disclosed by operation of law, provided that the
                           party receiving the request for the information has
                           fully complied with its obligations under Section
                           14.(b)(iv);

                  v.       Was developed by the receiving party without the
                           developing persons having access to any of the
                           Confidential Information received from the other
                           party;

                  vi.      Is authorized in writing by the disclosing party to
                           be released or is designated in writing by the source
                           as no longer being confidential or proprietary.

         d.       It is agreed that a violation of any of the provisions of this
                  Section will cause irreparable harm and injury to the
                  disclosing party and that party shall be entitled, in addition
                  to any other rights and remedies it may have at law or in
                  equity, to seek an injunction enjoining and restraining the
                  receiving party from doing or continuing to do any such act
                  and any other violations or threatened violations of this
                  Section.

15.      PUBLICITY

         Each party agrees not to provide copies of this Agreement, or otherwise
         disclose the terms of this Agreement, to any third party without the
         prior written consent of the other party; provided, however, that
         either party may, without obtaining the other party's consent, provide
         copies or make disclosures to prospective purchasers of the business of
         such party, 


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<PAGE>   14



         such party's affiliates, to comply with applicable laws or regulations
         or any regulatory or judicial body requesting such information. The
         parties further agree to submit to one another, for written approval,
         all advertising, sales promotion, press releases and other publicity
         matters relating to the Services performed pursuant to this Agreement,
         when its respective name or mark is mentioned or language from which
         the connection of said name or mark may be inferred or implied. The
         parties further agree not to publish or use such advertising, sales
         promotions, press releases, or publicity matters without such prior
         written approval. Any approval required under this Section shall not be
         unreasonably withheld or delayed by either party.

16.      TRADEMARKS AND TRADE NAMES

         Except as specifically set out in the 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, unless written permission is granted by the
         other party prior to usage.

17.      COMPLIANCE WITH LAWS

         The parties hereto shall comply with the provisions of all applicable
         federal, state, and local laws, ordinances, regulations and codes
         (including procurement of required permits or certificates) in their
         respective performance under this Agreement including, but not limited
         to, the Fair Labor Standards Act of 1938, safety and environmental
         laws, rules and regulations, any laws, rules and regulations regarding
         wages, hours, fringe benefits and taxes, and federal and state
         Occupational Safety and Health Act Laws.

18.      FORCE MAJEURE

         If performance of this Agreement is prevented, restricted or interfered
         with by reason of acts of God, wars, revolution, civil commotion, acts
         of public enemy, embargo, acts of government in its sovereign capacity,
         labor difficulties, including without limitation, strikes, slowdowns,
         picketing or boycotts, or other circumstances beyond the reasonable
         control and not involving any fault or negligence of the party
         affected, the party affected, upon giving prompt notice to the other
         party, shall be excused from such performance on a day-to-day basis
         during the continuance of such prevention, restriction, or interference
         (and the other party shall likewise be excused from performance of its
         obligations on a day-to-day basis during the same period), provided,
         however, that the party so affected shall use its best reasonable
         efforts to avoid or remove such causes of nonperformance and both
         parties shall proceed immediately with the performance of their
         obligations under this Agreement whenever such causes are removed or
         cease.

19.      CENTURY COMPLIANCE

         LICENSOR represents and warrants that by June 30, 1999, its Paging
         System and any software provided to RESELLER for use in association
         with the Services is capable of correctly processing, providing and
         receiving date data as well as properly exchanging accurate date data
         with all products (for example hardware, software and firmware) with
         which its Paging System and software is designed to be used and will
         not malfunction or cease to function due to an inability to correctly
         process such date data, including, but not limited to, transitions to
         or from the years 1999 to 2000.


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<PAGE>   15


20.      INDEMNIFICATION

         a.       LICENSOR shall indemnify, defend, and hold harmless RESELLER
                  and its affiliates, shareholders, directors, officers,
                  employees, contractors, agents and other representatives from
                  and against all demands, claims, damages, liabilities,
                  expenses (including reasonable fees and disbursements of
                  counsel), judgments, settlements and penalties of every kind
                  (collectively "Claims") based on (i) personal injury, death,
                  or property damage arising from or related to
                  LICENSOR's (either directly or through its officers, agents,
                  subcontractors or representatives) negligence or misconduct in
                  or related to performance of the Services under this
                  Agreement, or (ii) violation of any term of this Agreement or
                  matters referred to in Subsection 20 (b) below, provided,
                  however the obligation set out in this Section (ii) shall not
                  apply to Claims arising from or related to; (1) violations of
                  any term of this Agreement of the type that provides a
                  specific remedy (to include Liquidated Damages set forth in
                  Exhibit B), or; (2) guarantees or express warranties given by
                  RESELLER to its subscribers. The preceding proviso shall not
                  apply to Claims of third parties to the extent that they are
                  based on actual gross negligence or willful misconduct of
                  LICENSOR. The foregoing indemnity shall not apply in the case
                  of Claims which solely arise from the negligence, misconduct
                  or other fault of RESELLER. It shall apply, however, if a
                  Claim is the result of the joint negligence, joint misconduct,
                  or joint fault of LICENSOR and RESELLER, but in such a case
                  the amount of the Claim for which RESELLER is entitled to
                  indemnification shall be limited to that portion of such Claim
                  attributable to the negligence, misconduct or other fault of
                  LICENSOR. The obligations of this provision are in addition to
                  LICENSOR's obligation to provide insurance and shall not be
                  limited by any limitation on the amount or type of damages,
                  compensation or benefits payable by LICENSOR under the
                  Worker's Compensation Acts, Longshoremen and Harborworker's
                  Act, Disability Benefits Act or any other employee benefit
                  act.

         b.       Without limitation of 20 (a) above, LICENSOR shall, to the
                  fullest extent permitted by law, defend, indemnify and hold
                  harmless RESELLER, its officers, agents and employees, from
                  all Claims of every kind arising from or related to the
                  following matters:

                  i.       LICENSOR's failure to comply with all federal, state
                           or local laws, rules or regulations applicable to
                           LICENSOR's employees, including, without limitation,
                           the laws, rules or regulations referred to in Section
                           17, COMPLIANCE WITH LAWS and Section 25, TAXES;

                  ii.      LICENSOR's failure to comply with terms of Section
                           14, CONFIDENTIAL INFORMATION, regarding proprietary
                           information of RESELLER;

                  iii.     LICENSOR's failure to pay all fees and royalties for
                           the use of patented articles or methods in connection
                           with the Services;

                  iv.      LICENSOR's failure to obtain or maintain the Permits
                           referred to in Section 23, PERMITS, except for those
                           Permits that RESELLER has expressly 


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<PAGE>   16



                           agreed to obtain and maintain at RESELLER's expense;

                  v.       Contributions to multiemployer pension plans
                           affecting LICENSOR's employees;

                  vi.      Any mechanics' or materialmen's liens or any other
                           liens or encumbrances filed in respect of or placed
                           upon any real property or improvements owned or
                           leased by RESELLER as a result of any Services
                           performed by or any other act or omission on the part
                           of LICENSOR or any subcontractor or other person
                           claiming by, through or under LICENSOR; or

                  vii.     Any injury, sickness, disease or death of any person,
                           damage to any properties or assets or remediation of
                           any soil, surface water or groundwater resulting from
                           the processing, use, distribution, treatment,
                           storage, placement, removal, transportation or
                           disposal of any Hazardous Materials by LICENSOR or
                           its officers, agents subcontractors or
                           representatives.

         c.       RESELLER agrees to indemnify, defend and hold harmless
                  LICENSOR and its affiliates, shareholders, directors,
                  officers, employees, contractors, agents and other
                  representatives from and against any and all Claims arising
                  from or related to:

                  i.       Any negligent misrepresentations of the Services to
                           RESELLER's subscribers; and

                  ii.      Contributions to multiemployer pension plans
                           affecting RESELLER's employees.

         d.       RESELLER shall promptly notify LICENSOR in writing of any
                  suits, Claims or demands covered by this indemnity. Promptly
                  after receipt of such notice, LICENSOR shall assume the
                  defense of such claim with counsel reasonably satisfactory to
                  RESELLER. If LICENSOR fails, within a reasonable time after
                  receipt of such notice, to assume the defense with counsel
                  reasonably satisfactory to RESELLER, or if, in the reasonable
                  judgment of RESELLER, a direct or indirect conflict of
                  interest exists between the parties with respect to the Claim,
                  or if in the sole judgment of RESELLER the assumption and
                  conduct of the defense by LICENSOR would materially and
                  adversely affect RESELLER in any manner or prejudice its
                  ability to conduct a successful defense, then RESELLER shall
                  have the right to undertake the defense, compromise and
                  settlement of such Claim for the account and at the expense of
                  LICENSOR. Notwithstanding the above, if RESELLER in its sole
                  discretion so elects, RESELLER may also participate in the
                  defense of such actions by employing counsel at its expense,
                  without waiving LICENSOR's obligations to indemnify or defend.
                  An indemnified party shall not settle or compromise any Claims
                  against it or consent to the entry of any judgments without
                  the prior written consent of the indemnifying party and
                  without an unconditional release of all liability by each
                  claimant or plaintiff to the indemnified party.

         e.       RESELLER and LICENSOR each agree to maintain during the term
                  hereof all insurance and/or bonds required by law or this
                  Agreement, including, but not limited 


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<PAGE>   17


                  to (i) Workers' Compensation and related insurance as
                  prescribed by applicable law; (ii) employer's liability
                  insurance with limits of at least $1,000,000 for each
                  occurrence, and (iii) 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. 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.

21.      WARRANTY

         a.       Except as expressly set forth in this Agreement, 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. If,
                  notwithstanding the other terms of this Agreement, LICENSOR is
                  liable for any mistakes, omissions, interruptions, delays,
                  errors, or defects in transmission of pages on LICENSOR's
                  Paging System, then the parties agree that, except as set
                  forth in Exhibit B, LICENSOR shall not be liable beyond the
                  actual and direct loss arising therefrom. However, LICENSOR's
                  liability to RESELLER for each period of service disruption or
                  defect in transmission will in no event exceed the amount of
                  Fifty thousand dollars ($50,000) provided that nothing herein
                  shall limit any amounts due to RESELLER pursuant to Exhibit B.
                  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. The preceding two
                  sentences shall not limit a party's obligations under Section
                  22, INFRINGEMENT, or indemnification for third party claims
                  arising from death, or personal injury, or willful misconduct
                  of a party, or damage to tangible property, or gross
                  negligence of a party.

         b.       Section 20 (a) shall not apply to any Losses arising out of
                  any claim by a Subscriber of RESELLER, added by RESELLER after
                  the execution of this Agreement, unless the agreement between
                  RESELLER and such Subscriber contains provisions substantially
                  as follows:

                  i.       Disclaimer of Warranties. [GTE OR ANY THIRD PARTY
                           SERVICE PROVIDER] DISCLAIMS ALL EXPRESS OR IMPLIED
                           WARRANTIES WITH RESPECT TO THE EQUIPMENT AND
                           SERVICES, INCLUDING WITHOUT 


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<PAGE>   18



                           LIMITATION ANY WARRANTY OF MERCHANTABILITY OR FITNESS
                           FOR A PARTICULAR PURPOSE.

                  ii.      Limitation of Liability. Customer acknowledges that
                           pages and messages may be lost or garbled for many
                           reasons other than the negligence of [GTE OR ANY
                           THIRD PARTY SERVICE PROVIDER], such as dialing
                           errors, power failures, network equipment failures,
                           electronic interference and the recipient's messaging
                           device being turned off or outside the coverage area
                           or having a weak battery. [GTE OR ANY THIRD PARTY
                           SERVICE PROVIDER], SHALL NOT BE LIABLE FOR ANY
                           DAMAGES ARISING OUT OF (i) LATENT OR PATENT EQUIPMENT
                           OR SERVICES DEFECTS, OR (ii) LOSS OF USE OF ANY OF
                           THE EQUIPMENT OR SERVICES, OR (iii) ANY ACCIDENT OR
                           INJURY CAUSED BY THE EQUIPMENT OR THE SERVICES WHEN
                           SUCH ACCIDENT OR INJURY IS NOT DUE TO THE GROSS
                           NEGLIGENCE OR WILLFUL MISCONDUCT OF [GTE OR ANY THIRD
                           PARTY SERVICE PROVIDER], OR (iv) ANY FAILURE TO
                           ACCURATELY TRANSMIT A MESSAGE OR ANY RECIPIENT'S
                           FAILURE TO RECEIVE A MESSAGE UNLESS SUCH FAILURE IS
                           DUE TO [GTE'S OR ANY THIRD PARTY SERVICE PROVIDER'S]
                           GROSS NEGLIGENCE OR WILLFUL MISCONDUCT. [GTE OR ANY
                           THIRD PARTY SERVICE PROVIDER] SHALL NOT BE LIABLE FOR
                           LOST PROFITS OR EXEMPLARY, SPECIAL, INCIDENTAL,
                           CONSEQUENTIAL OR PUNITIVE DAMAGES ARISING DIRECTLY OR
                           INDIRECTLY OUT OF THIS AGREEMENT, THE EQUIPMENT OR
                           THE SERVICES. IF ANY LIMITATION OF LIABILITY SET
                           FORTH HEREIN IS UNENFORCEABLE OR INAPPLICABLE FOR ANY
                           REASON, [GTE'S OR ANY THIRD PARTY SERVICE PROVIDER'S]
                           MAXIMUM AGGREGATE LIABILITY TO CUSTOMER UNDER ANY
                           LEGAL THEORY (INCLUDING ITS OWN NEGLIGENCE) FOR
                           DAMAGES ARISING DIRECTLY OR INDIRECTLY OUT OF THIS
                           AGREEMENT, THE EQUIPMENT OR THE SERVICES WILL NOT
                           EXCEED THE LESSER OF THE ACTUAL DIRECT DAMAGES
                           SUFFERED BY CUSTOMER OR THE AMOUNT PAID BY CUSTOMER
                           FOR THE SPECIFIC UNIT OF EQUIPMENT OR SERVICE AND
                           SERVICE PERIOD OUT OF WHICH THE CLAIM AROSE.

22.      INFRINGEMENT

         a.       LICENSOR agrees to indemnify, defend and hold harmless
                  RESELLER and its affiliates, shareholders, directors,
                  officers, employees, contractors, agents and other
                  representatives from and against any and all Claims (as
                  defined in Section 20 (a)) arising from or relating to any
                  actual or alleged infringement or misappropriation of any
                  patent, trademark, copyright, trade secret or any actual or
                  alleged violation of any other intellectual property rights
                  arising from or in connection with the software provided or
                  the Services performed under this Agreement regardless of
                  whether such software or Services form the entire basis or
                  only a portion of the basis for such claims of infringement,
                  misappropriation or violation. Notwithstanding anything to the
                  contrary contained in this Agreement (including, but not
                  limited to, Section 20 (a), the provisions of this Section 22
                  (a) shall govern the rights of RESELLER and its affiliates,
                  shareholders, directors, officers, employees, contractors,
                  agents and 



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<PAGE>   19


                  other representatives to indemnification for claims of
                  infringement, misappropriation or violation of intellectual
                  property rights.

         b.       The provisions and procedures set forth in Section 20. (d)
                  shall apply in the case of any claims of infringement,
                  misappropriation or violation of intellectual property rights
                  for which indemnification will be sought hereunder.

         c.       Without limitation of Section 22 (a), if the sale or use of
                  the software or Services is enjoined, LICENSOR shall, at
                  LICENSOR's option and LICENSOR's expense, either:

                  i.       Procure for RESELLER the right to use the software or
                           Services;

                  ii.      Replace the software or Services with equivalent,
                           noninfringing software or Services;

                  iii.     Modify the software or Services so they become
                           noninfringing, or

                  iv.      If (i), (ii), and (iii) are not practicable, subject
                           to RESELLER's consent, remove the software or
                           Services and refund the purchase price, including
                           transportation, installation, removal and other
                           incidental charges.

23.      PERMITS

         Unless otherwise specifically provided for in this Agreement, LICENSOR
         shall obtain and keep in full force and effect, at its expense, any
         permits, licenses, consents, approvals and authorizations (Permits)
         necessary for the performance and completion of the Services.

24.      ASSIGNMENT

         a.       Except as otherwise provided herein, the rights and
                  obligations of the parties hereunder shall neither be assigned
                  nor delegated without the prior written consent of the other
                  party, which shall not be unreasonably withheld or delayed;
                  provided, however, 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 that
                  was such a parent, subsidiary or affiliate at the time of
                  execution of this Agreement or is listed in any Exhibit A
                  furnished to LICENSOR from time to time. 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 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.


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<PAGE>   20


25.      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 imposed by law upon RESELLER, or any similar taxes or assessments
         as applicable, with respect to transactions under this Agreement. Taxes
         and assessments 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 or assessment for which a
         valid exemption certificate acceptable to the applicable state or local
         taxing authorities is furnished by RESELLER to LICENSOR.

26.      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
                  specifying in detail 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. Either Party shall be entitled, at their
                  own expense and 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.

27.      RIGHT OF ACCESS

         LICENSOR shall permit RESELLER's predesignated representative(s),
         limited to three predefined representatives per state, reasonable
         supervised access to its facilities in connection with performance of
         Services under this Agreement. Both parties agree that no charge shall
         be made for such visits and that RESELLER shall provide a minimum of
         one (1) hour notice prior to arriving at any LICENSOR owned facility
         which is regularly staffed or during any time that a facility is
         involved in a service affecting issue. RESELLER shall provide
         reasonable notice prior to arriving at any LICENSOR owned facility
         which is not staffed and is not experiencing service affecting issues.

28.      TERMINATION

         a.       After the initial three (3) year term of the Agreement,
                  LICENSOR may:

                  i.       terminate RESELLER's right to add additional
                           subscribers upon provision to RESELLER of eighteen
                           (18) months prior written notice. This notice may not
                           be given until completion of the initial three (3)
                           year term. During this eighteen (18) month period
                           RESELLER may add additional Subscribers per the terms
                           of this Agreement. After the eighteenth (18th) month
                           RESELLER may not add additional Subscribers. During
                           this eighteen month period, LICENSOR shall be 


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<PAGE>   21



                           bound by all terms of this Agreement, including
                           Exhibit B, and all applicable Liquidated Damages.

                  ii.      however, after the eighteen (18) month notice in
                           Section 28(a)(i), LICENSOR must provide an additional
                           prior written notice of twenty-four (24) months if
                           LICENSOR intends to terminate Service to the existing
                           RESELLER Subscriber base under the terms of this
                           Agreement. During this twenty-four (24) month notice
                           period, LICENSOR may increase prices at the end of
                           each twelve (12) month period in Exhibit C by the
                           greater of [*] or the difference between the Consumer
                           Price Index at the end of the previous twelve (12)
                           month period and the then current Consumer Price
                           Index, as defined within this Agreement, with a
                           minimum of thirty (30) days written notice to
                           RESELLER. LICENSOR has the right but not the
                           obligation to terminate Service to RESELLER's
                           existing Subscriber base after completion of the
                           additional twenty-four (24) month notice period. Both
                           parties are bound by all the terms of this Agreement
                           until such time as all notification requirements and
                           waiting periods are satisfied per this section of the
                           Agreement OR until such time as all RESELLER
                           Subscribers have been migrated from LICENSOR's
                           network, whichever happens sooner. However, if
                           RESELLER's total subscriber base falls below [*}
                           subscribers at any time during this twenty-four (24)
                           month waiting period, then LICENSOR shall not be
                           liable for the Liquidated Damages as assessed in
                           Exhibit B, however, LICENSOR will still be
                           responsible for meeting all other terms of the
                           Agreement

         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:

                  i.       The other files a voluntary petition in bankruptcy;

                  ii.      The other is adjudged bankrupt;

                  iii.     A court assumes jurisdiction of the assets of the 
                           other under a federal reorganization act;

                  iv.      A trustee or receiver is appointed by a court for all
                           or a substantial portion of the assets of the other;

                  v.       Other becomes insolvent or suspends its business; or

                  vi.      The other makes an assignment of its assets for the
                           benefit of its creditors, except as required in the
                           ordinary course of business.

         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.


PageMart 09/28/98                                                 -CONFIDENTIAL-
                                       19


*  CONFIDENTIAL INFORMATION HAS BEEN DELETED. THE OMITTED MATERIAL HAS BEEN 
   FILED SEPARATELY WITH THE COMMISSION PURSUANT TO AN APPLICATION FOR 
   CONFIDENTIAL TREATMENT.

<PAGE>   22



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

                  i.       LICENSOR agrees to give RESELLER, at no cost to
                           RESELLER, all Direct Inward Dial numbers associated
                           with all RESELLER's customer accounts/pagers provided
                           that it is both, technically possible to do so, and
                           allowable from a regulatory perspective, with a
                           Glenayre paging terminal. Any numbers and associated
                           ports must be moved to a RESELLER owned terminal.
                           These numbers will not be allowed to reside on a
                           LICENSOR owned paging terminal without the prior
                           written consent of both parties. RESELLER and
                           LICENSOR will each be responsible for any of their
                           own incurred administrative costs associated with
                           such transfers.

                  ii.      RESELLER agrees to proactively transfer no more than
                           [*] of the total subscriber base per month, although
                           the effective rate of transfer will be greater than
                           [*] due to normal churn of RESELLER's subscriber
                           base.

                  iii.     LICENSOR is responsible for costs associated with
                           ensuring technical compliance of all LICENSOR owned
                           systems.

                  iv.      Subsection (d) will not apply after a facilities
                           based direct competitor of LICENSOR gains control of
                           RESELLER's business related to the scope of this
                           Agreement, whether by RESELLER's sale or other
                           transfer of this business or by a third parties
                           purchase or other acquisition of RESELLER. RESELLER's
                           pending transaction with Bell Atlantic is excluded
                           from this subsection (e).

29.      DISPUTE RESOLUTION

         a.       The parties desire to resolve certain disputes, controversies
                  and claims arising out of this Agreement without litigation.
                  Accordingly, except in the case of (i) a dispute, controversy
                  or claim relating to a breach or alleged breach on the part of
                  either party of the provisions of Section 14, CONFIDENTIAL
                  INFORMATION, (ii) a suit, action or proceeding to compel
                  LICENSOR to comply with its obligations to indemnify RESELLER
                  pursuant to this Agreement or (iii) a suit, action or
                  proceeding to compel either party to comply with the dispute
                  resolution procedures set forth in this Section, the parties
                  agree to use the following alternative procedure as their sole
                  remedy with respect to any dispute, controversy or claim
                  arising out of or relating to this Agreement or its breach.
                  The term "Arbitrable Dispute" means any dispute, controversy
                  or claim to be resolved in accordance with the dispute
                  resolution procedure specified in this Section.

         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 


PageMart 09/28/98                                                 -CONFIDENTIAL-
                                       20


*  CONFIDENTIAL INFORMATION HAS BEEN DELETED. THE OMITTED MATERIAL HAS BEEN 
   FILED SEPARATELY WITH THE COMMISSION PURSUANT TO AN APPLICATION FOR 
   CONFIDENTIAL TREATMENT.

<PAGE>   23


                  Arbitrable Dispute arising under this Agreement. The parties
                  intend that these negotiations be conducted by nonlawyer,
                  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, shall be exempt from discovery and production, and
                  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 Arbitrable Dispute
                  within sixty (60) days of the initial written request, the
                  Arbitrable 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 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 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 Arbitrable Dispute by issuing a
                  written opinion within thirty (30) days after the close of
                  hearings. The arbitrator shall have no power or authority to
                  make awards or issue orders of any kind except as permitted by
                  this Agreement and substantive law, and in no event shall the
                  arbitrator have the authority to make any award that provides
                  for punitive or exemplary damages. The arbitrator's decision
                  shall follow the plain meaning of this Agreement and the
                  relevant documents. 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 documents (to include search time
                  and reproduction time costs). The parties shall equally share
                  the fees of the arbitration and the arbitrator.

30.      NOTICES

         Any written notice either party may give the other concerning the
         subject matter of this Agreement shall be in writing and given or made
         by means of 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:


PageMart 09/28/98                                                 -CONFIDENTIAL-
                                       21

<PAGE>   24



                  To LICENSOR:        At LICENSOR's address shown on the first 
                                      page of this Agreement.

                  To RESELLER:        GTE Supply
                                      700 Hidden Ridge (HQW03N42)
                                      Irving, Texas  75038
                                      Attention: Contract Management

         Written notices for change in ownership, change in name of firm, or
         change in mailing address must be given by LICENSOR by mailing to
         RESELLER within thirty (30) days of such change. A change in ownership
         shall be defined as any one person, entity, or legal entity acquiring
         more than ten percent (10%) ownership of LICENSOR's company and or
         publicly traded stock. Notices for change in ownership must include the
         names of all new owners or officers, registered agent for service of
         process and state of incorporation or organization.

31.      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 be 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.

32.      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 remaining portion of this Agreement
         without including therein any such part or portion which may, for any
         reason, be hereafter declared invalid.

33.      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.

34.      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.

35.      CHOICE OF LAW

         The construction, interpretation and performance of this Agreement
         shall be 

PageMart 09/28/98                                                 -CONFIDENTIAL-
                                       22

<PAGE>   25

         governed by and construed in accordance with the domestic laws of the
         State of Texas.

36.      ENTIRE AGREEMENT

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

37.      SIGNATURES

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


GTE Communication Systems            PageMart Wireless, Inc.
Corporation

By: /s/ M. R. REDMOND                By: /s/ N. ROSS BUCKENHAM
   ---------------------                -----------------------------
Name:   M. R. Redmond                Name:   N. Ross Buckenham
     -------------------                  ---------------------------
Title: AVP-Contract Mgt              Title:  President
      ------------------                   --------------------------
Date:  9/29/98                       Date:   9/28/98
     -------------------                  ---------------------------



PageMart 09/28/98                                                 -CONFIDENTIAL-
                                       23

<PAGE>   26





                                    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.

PageMart (9/28/98)                                                -CONFIDENTIAL-
                                       A-1

<PAGE>   27



                                    EXHIBIT A

                             GTE AFFILIATED ENTITIES

              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

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

PageMart (9/28/98)                                                -CONFIDENTIAL-
                                       A-2

<PAGE>   28


                                   EXHIBIT A
                            GTE AFFILIATED ENTITIES

     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

     Televac, Inc.

GTE Transfer Corporation




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                                       A-3

<PAGE>   29




                                    EXHIBIT B
                             Service Level Agreement


LICENSOR agrees to maintain the service levels described herein. LICENSOR's
service level agreement applies only to the infrastructure managed and
maintained by LICENSOR. LICENSOR is not responsible for service levels for the
infrastructure maintained by RESELLER (i.e. the Hawaii network infrastructure
and all RESELLER paging terminals).

LICENSOR will provide service to RESELLER in three different manners: Full
RESELLER Paging Services, Quasi-RESELLER Paging Services, and Transmission Only
Paging Services.

         Under Full RESELLER Paging Services the RESELLER will procure customers
         which will be activated on one of LICENSOR's paging terminals and in
         LICENSOR's billing system via PRIME, Vantive, WinFast, ActFast,
         Dial-Now, or other LICENSOR provided activation systems. LICENSOR will
         provide the pager number and all in-bound calling circuits. When a
         valid customer receives a page the in-bound call is accepted by
         LICENSOR (at the terminal), the customer is validated in the terminal,
         and the page is transmitted to the transmitters in the correct Coverage
         zone via satellite simulcast. The transmitters then send the page out
         via one of LICENSOR's frequencies (that frequency which matches the
         receiver in that specific customer's pager). Multiple sub-services are
         to be provided by LICENSOR to RESELLER under this service as defined
         below.

         Under Quasi-RESELLER Paging Services the RESELLER will procure
         customers which will be activated on a RESELLER paging terminal, one of
         LICENSOR's paging terminals, and LICENSOR's billing system via PRIME,
         Vantive, WinFast, ActFast, Dial-Now, or other LICENSOR provided
         activation systems. When a valid customer receives a page the in-bound
         call is accepted by RESELLER (at the terminal), the customer is
         validated in the terminal, and the page is transmitted to a LICENSOR
         terminal via TNPP. The data is directed by LICENSOR's terminal to the
         transmitters in the correct Coverage zone via satellite simulcast. The
         transmitters then send the page out via one of LICENSOR's frequencies
         (that frequency which matches the receiver in that specific customer's
         pager). Multiple sub-services are to be provided by LICENSOR to
         RESELLER under this service as defined below.

         Under Transmission Only Paging Services the RESELLER will procure
         customers which will be activated on a RESELLER paging terminal via a
         RESELLER provided activation system. Billing will be based on the
         amount of data that passes through the LICENSOR's system as defined in
         the pricing section of this contract. When a valid customer receives a
         page the in-bound call is accepted by RESELLER (at the RESELLER owned
         terminal), the customer is validated in the terminal, and the page is
         transmitted to a LICENSOR terminal via TNPP. The data is directed by
         LICENSOR's terminal to the transmitters in the correct Coverage zone
         via satellite simulcast. The transmitters then send the page out via
         one of LICENSOR's frequencies (that frequency which matches the
         receiver in that specific customer's pager). Multiple sub-services are
         to be provided by LICENSOR to RESELLER under this service as defined
         below.


PageMart 09/28/98                                                 -CONFIDENTIAL-
                                       B-1

<PAGE>   30


[*]


GTE Communication Systems                    PageMart Wireless, Inc.


By: /s/ M. R. REDMOND                        By: /s/ N. ROSS BUCKENHAM
   --------------------------                   --------------------------  
                                                                            
Name:   M. R. Redmond                        Name:   N. Ross Buckenham
     ------------------------                     ------------------------  
                                                                            
Title:  AVP-Contract Mgt                     Title:  President
      -----------------------                      -----------------------  
                                                                            
Date:   9/29/98                              Date:   9/28/98                  
     ------------------------                     ------------------------  




PageMart (09/28/98)                                               -CONFIDENTIAL-



*  CONFIDENTIAL INFORMATION HAS BEEN DELETED. THE OMITTED MATERIAL HAS BEEN 
   FILED SEPARATELY WITH THE COMMISSION PURSUANT TO AN APPLICATION FOR 
   CONFIDENTIAL TREATMENT.

<PAGE>   31


                                    EXHIBIT C
                                     Pricing


Listed below are the three pricing options available to RESELLER:


1.       PRIME PROVISIONED SUBSCRIBER MESSAGING SERVICES

         Services delivered to RESELLER customers utilizing a RESELLER or
         LICENSOR owned paging terminal for which LICENSOR's administrative
         system (PRIME) is used to provision the subscribers and collect call
         counts.

2.       TNPP NON-PROVISIONED SUBSCRIBER MESSAGING SERVICES

         Services delivered to RESELLER customers for which RESELLER provides
         all provisioning services and does not utilize LICENSOR's provisioning
         systems nor paging terminals managed or maintained by LICENSOR. Traffic
         rated according to this pricing model must be delivered at RESELLER's
         cost to a LICENSOR network gateway (RTS Router) for direct distribution
         to the satellite uplink without passing through one of LICENSOR's
         paging terminals.

3.       TNPP NON-PROVISIONED MACHINE MESSAGING SERVICES

         Services delivered to RESELLER customers for which RESELLER provides
         all provisioning services and does not utilize LICENSOR's provisioning
         systems nor paging terminals managed or maintained by LICENSOR. Traffic
         rated according to this pricing model must be delivered at RESELLER's
         cost to a LICENSOR network gateway (RTS Router) for direct distribution
         to the satellite uplink without passing through one of LICENSOR's
         paging terminals. Each message shall consist of no more than three (3)
         characters.






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                                       C-1

<PAGE>   32

                                    EXHIBIT C
                 PRIME PROVISIONED SUBSCRIBER MESSAGING SERVICES
                              ALPHANUMERIC PRICING


<TABLE>
<CAPTION>
                                PER MO, PER UNIT         TEXT NETWORK         NUMERIC NET.         US 800 /          US 800 / 888
COVERAGE                       FLEX NETWORK RATE        OVERCALL LEVEL       OVERCALL LEVEL       888 CHARGE        OVERCALL LEVEL
--------                       -----------------        --------------       --------------       ----------        --------------
<S>                            <C>                      <C>                   <C>                 <C>               <C>    

Local - Tier I                        *                      *                   *                   *                   *   

Local - Tier II                       *                      *                   *                   *                   *   

Local Tier III                        *                      *                   *                   *                   *   

Text Roam
    US only (1)                       *              counts towards local coverage listed above

Text Roam
    International (2)                 *              counts towards local coverage listed above

Statewide                             *                      *                   *                   *                   *   

Region                                *                      *                   *                   *                   *   

Dual Region                           *                      *                   *                   *                   *   

Norpac                                *                      *                   *                   *                   *   

SF or LA plus
     Las Vegas                        *                      *                   *                   *                   *   

California State
     plus Las Vegas                   *                      *                   *                   *                   *   

Nationwide
    US 48 States                      *                      *                   *                   *                   *   
    US Extended (1)                   *                      *                   *                   *                   *   

International (2)                     N/A            See International Text Roam above.
</TABLE>


**Alphanumeric message allotment to include 100 characters per message.
 - LOCAL AND STATEWIDE ONLY, AGGREGATED AT LISTED SERVICE LEVELS. NO OTHER
   SERVICES ARE AGGREGATED.
 - GTE will offer industry standard overcall thresholds and rates in order to
   create financial opportunities for GTE or penalties for abusers of the
   network.
 - GTE user's usage profile does not change significantly from the current or
   the aggregation rules will be reviewed.
 - If a GTE subscriber originates more than 500 text messages in one month, GTE
   and PageMart will discuss the validity of the application and remove that
   customer from aggregation on the basis that at such a high level, over 16
   text messages per day, PageMart is not fairly compensated.
 - International Roaming requires equal level of service of U.S. service on
   929.6625 Mhz frequency.
 - All rates are per month unless otherwise noted.
 - FLEX Service only; "( )" denotes pocsag rate -- not applicable for new
   subscribers, but will apply to RESELLER's current pocsag inventory
 - Tier I (LA / San Diego), Tier II (Hawaii), Tier III (All areas not Tier I or
   Tier II).
 (1) 48 States, Alaska/Hawaii, Puerto Rico/Virgin Islands, Bahamas
 (2) 48 States, Canada, Alaska/Hawaii, Puerto Rico/Virgin Islands, Bahamas,
     Mexico, Central America



PageMart (9/28/98)                                                -CONFIDENTIAL-
                                       C-2


*  CONFIDENTIAL INFORMATION HAS BEEN DELETED. THE OMITTED MATERIAL HAS BEEN 
   FILED SEPARATELY WITH THE COMMISSION PURSUANT TO AN APPLICATION FOR 
   CONFIDENTIAL TREATMENT.

<PAGE>   33

                                    EXHIBIT C
                 PRIME PROVISIONED SUBSCRIBER MESSAGING SERVICES
                                 NUMERIC PRICING


<TABLE>
<CAPTION>
                                     Per Mo, Per Unit            Network            US 800/888                800/888
Coverage                            Flex Network Rate        Overcall Level           Charge              Overcall Level
--------                            -----------------        --------------           ------              --------------
<S>                                <C>                      <C>                    <C>                   <C>    
Local                                        *                      *                   *                        *

Local LA/SD                                  *                      *                   *                        *

Numeric Roam
      US only (1)                            *            counts towards local coverage listed above

Numeric Roam
      International (2)                      *            counts towards local coverage listed above

Statewide                                    *                      *                   *                        *

Region                                       *                      *                   *                        *

Dual Region                                  *                      *                   *                        *

Norpac                                       *                      *                   *                        *

Seaboard Region                              *                      *                   *                        *

SF or LA plus                                                                                        
     Las Vegas                               *                      *                   *                        *

California State
     Plus Las Vegas                          *                      *                   *                        *

Nationwide
      US 48 States                           *                      *                   *                        *
      US Extended (1)                        *                      *                   *                        *

International (2)                          N/A            See International Numeric Roam above.

</TABLE>

**Price includes Local DID.
 - NUMERIC NETWORK OVERCALLS ARE AGGREGATED WITHIN THREE CATEGORIES: (1) LOCAL,
   ROAM, AND STATEWIDE; (2) REGIONAL; AND (3) NATIONWIDE AND EXTENDED 
   NATIONWIDE. AGGREGATE BILLING DOES NOT INCLUDE 800/888 SERVICE. OVERCALL 
   CHARGES ARE ASSESSED WHEN AGGREGATED THRESHOLD IS CROSSED.
 - GTE will offer industry standard overcall thresholds and rates in order to
   create financial opportunities for GTE or penalties for abusers of the
   network.
 - GTE user's usage profile does not change significantly from the current or
   the aggregation rules will be reviewed.
 - International Roaming requires equal level of service of U.S. service on
   929.6625 Mhz frequency.
 - All rates are per month unless otherwise noted.
 - FLEX Service only; "( )" denotes pocsag rate -- not applicable for new
   subscribers, but will apply to RESELLER's current pocsag inventory.
 (1) 48 States, Alaska/Hawaii, Puerto Rico/Virgin Islands, Bahamas
 (2) 48 States, Canada, Alaska/Hawaii, Puerto Rico/Virgin Islands, Bahamas,
     Mexico, Central America




PageMart (9/28/98)                                                -CONFIDENTIAL-
                                       C-3


*  CONFIDENTIAL INFORMATION HAS BEEN DELETED. THE OMITTED MATERIALS HAVE BEEN 
   FILED SEPARATELY WITH THE COMMISSION PURSUANT TO AN APPLICATION FOR 
   CONFIDENTIAL TREATMENT.

<PAGE>   34

                                    EXHIBIT C
               TNPP Non-Provisioned Subscriber Messaging Services
                                     Pricing


Pricing the same as Exhibit B Prime Provisioned Messaging Services except:

o        TNPP price does not include Local DID.

o        Numeric TNPP rates are discounted [*] from published PRIME rates and
         are for FLEX units only.

o        Alphanumeric TNPP rates are discounted [*] from published PRIME rates
         and are for FLEX units only.

o        LICENSOR will provide a monthly list for all customers using Roaming
         service.

o        [*]

o        TNPP circuits and licensing fees, to allow for pager provisionment,
         will be the financial responsibility of RESELLER.

o        Numeric overcalls [*] at per character based on 20 characters per
         numeric message, i.e., [*] per numeric overcall.


PageMart (9/28/98)                                                -CONFIDENTIAL-
                                       C-4


*  CONFIDENTIAL INFORMATION HAS BEEN DELETED. THE OMITTED MATERIAL HAS BEEN 
   FILED SEPARATELY WITH THE COMMISSION PURSUANT TO AN APPLICATION FOR 
   CONFIDENTIAL TREATMENT.

<PAGE>   35



                                    EXHIBIT C
                 TNPP Non-Provisioned Machine Messaging Services
                                     Pricing



o        To be discussed: Most Favored Nation clause will apply








PageMart (9/28/98)                                                -CONFIDENTIAL-
                                       C-5



<PAGE>   36




                                    EXHIBIT D
                              Authorized Equipment


PRODUCT NAME

Motorola Pronto - Flx
Motorola Bravo - Flx
Motorola Jazz - Flx
Motorola Express Extra - Flx
Motorola Express Ultra - Flx
Motorola Renegade - Flx*

Motorola Wordline Flx
Motorola Advisor Gold Flx
Motorola Advisor Elite Flx

Phillips Cobalt Flx
Phillips Myna Flx




*        Only units currently in RESELLER'S inventory (approximately 10,000) may
         be placed in service under LICENSOR'S Paging System

PageMart 09/28/98                                                 -CONFIDENTIAL-
                                       D-1

<PAGE>   37




                                    EXHIBIT E

                  RESELLER National Accounts Service Commitment


                  [*]





PageMart 09/28/98                                                 -CONFIDENTIAL-
                                       E-1



*  CONFIDENTIAL INFORMATION HAS BEEN DELETED. THE OMITTED MATERIAL HAS BEEN 
   FILED SEPARATELY WITH THE COMMISSION PURSUANT TO AN APPLICATION FOR 
   CONFIDENTIAL TREATMENT.

<PAGE>   38



                                    EXHIBIT F

                               Technical Standards

      (To be added within thirty (30) days after executing this Agreement)






PageMart 09/28/98                                                 -CONFIDENTIAL-
                                       F-1


<PAGE>   39

[PAGEMART LOGO]


PAGEMART STANDARDS AND TEST PROCEDURES FOR WIRELESS MESSAGING DEVICES

The following section will outline the general lab procedures utilized by
PageMart to evaluate and test the subscriber units submitted for acceptance.

1    Inspection of unit for manufacturing quality, finish and ruggedness.

2    Analysis of ease of unit operation (message recall, etc.) in conformance
     with supplied operating procedures.

3    Analysis of programming ease and feature availability.

4    Analysis of technical and programming manuals.

The following section will outline the testing of pager sensitivity, and other
specifications as deemed necessary, in a Model CC105EXX Crawford TEM Cell.

1    Locate "BEST POSITION" through trial and error placement in the Crawford
     cell or based on information supplied by the manufacturer.

2    By reiterative adjustment of signal level from the test signal generator
     (HP8648C with FLEX encoding option) the point at which 80% of the page
     sequences sent are decoded will be determined.

3    To arrive at a 90% signaling reliability, add 1.5 dB to the value measured
     above. THIS VALUE REPRESENTS OUR MEASURED SENSITIVITY FOR THE PAGER.

Our current benchmark level is -102dBm. Our expectation is for the sensitivity
of a pager in this environment and by this method be no worse than -95dBm.

The following section will outline the testing of pagers for high signal level
intermodulation rejection in the TEM cell:

1    Combine three HP8648 signal generators w/ encoders using a three-way
     splitter and feed the signal into the TEM cell.

2    Adjust sig. Gen. #1 and #2 (the unwanted signals) 929.6125MHz and
     929.5625MHz respectively, which create a third order hit on 929.66250 (the
     wanted signal frequency).

3    Set-up sig. Gen. #3 (the wanted signal) with pager appropriate modulation
     at 6400/4 Phase D on frequency 929.66250.

4    Adjust amplitude of all signal generators to -30dBm inside the cell
     compensating for any losses in the set-up. (PageMart set-up has a 20dB
     measured loss, therefore signal generators are set to -10dBm.)

5    The wanted signal is then decremented to failure and recorded.

6    THE DELTA OF THE WANTED TO THE UNWANTED SIGNALS REPRESENTS THE LEVEL OF
     INTERMODULATION REJECTION FOR THE PAGER AT -30dBm.

Our current benchmark level is 45dB of IMR @ -30dBm. Our expectation of any
device in this environment should be greater than 40dB of IMR @-30dBm.

Note*** If testing of pager high-level IM is accomplished by following
TIA/EIA-603 section 2.1.9 intermodulation Rejection, the following exceptions
apply:

1    In paragraph 2.1.9.2.c, increases the level of the "wanted" signal by 70
     dB. E.g., if reference sensitivity as measured in the TEM cell is -100
     dBm, the new applied level is -30 dBm.

2    Replace any reference to a SINAD measurement with the 80% paging
     reliability reference point.


                                                                              1


<PAGE>   40



At this point, RF Engineering will produce a brief report with subjective
evaluation factors and the results of sensitivity and I/M tests. This will be
submitted to management. If a decision is made to proceed, additional testing
will be done as follows.

Field testing will be done at worst-case signaling rates in the following
environments:

1.   The usual simulcast system locations in city, suburban and rural locations.

2.   Weak signal, usually rural, locations.

3.   In areas of known high-level IM.

4.   In other locations or cities as deemed necessary.


Field testing is accomplished in the following manner.

1.   Request the PageMart Communications Center to initiate numeric and/or
     alphanumeric sequential test pages through the appropriate paging terminal.

2.   Place all pagers under test (the five new units plus known units for
     reference) clipped to a copier paper box top or equivalent (each pager
     should be separated by as much distance as possible).

Setup the PageMart RF Engineering Grayson PageTracker with associated Notebook
computer (P5-75 or better) to measure received signal strength indication (RSSI)
and bit error rate (BER) on at least two receivers.

1.   One receiver will utilize an external magnetic mount quarter-wave whip
     antenna mounted on the test vehicle roof.

2.   The second receiver will utilize a two-way "rubber-ducky" type mobile radio
     antenna.

3.   Drive routes and locations that are previously defined and mapped in
     relation to the desired environments.

4.   Perform continuous testing by receiving periodic pages on specified drive
     routes at normal speeds.

5.   Perform testing at fixed locations by receiving groups of ten or more
     sequential pages. (Rotate pager position at least every 25 pages)

6.   Produce Graphical Information System (GIS) plots of BER and RSSI.

7.   Compare reliability data in relation to GIS BER and RSSI:

Within published coverage areas paging reliability should exceed 95%. In weak
signal locations performance of the units under test should be comparable to the
reference pager (+/- 5%). Other test locations should show paging reliability
statistics on the units under test comparable to the reference pager in terms of
pager reliability (+/- 5%).

PageMart RF Engineering will produce a summary report including data as required
with recommendations for management to decide on the purchase of production
quantities of the pager under test.



                                                                               2