<PAGE>
                                                                   EXHIBIT 10.15


                                                                  Execution Copy

                         ROAMING AGREEMENT FOR GSM/GPRS

                                     between

                          AT&T WIRELESS SERVICES, INC.
                   having its principal place of business at:

                     7277 164th Avenue NE, Redmond, WA 98052
                       (hereinafter referred to as "AWS")

                                       and

                          AMERICAN CELLULAR CORPORATION
                   having its principal place of business at:

                               14201 Wireless Way
                             Oklahoma City, OK 73134
                       (hereinafter referred to as "ACC")

The above-mentioned Parties agree to establish Roaming between each other and
their respective controlled Subsidiaries, by operating GSM digital cellular
telecommunications service on the terms and conditions as stated below.

In this GSM/GPRS Roaming Agreement is included the General Terms and Conditions
for GSM Roaming and the Annexes (GSM Association Permanent Reference Documents
AA.13 and AA.14).

All references to GSM should read "GSM 850; GSM 900 and/or GSM 1800/1900"

The term "Agreement" used throughout the General Terms and Conditions for GSM
Roaming shall mean this Roaming Agreement for GSM/GPRS and the General Terms and
Conditions for GSM Roaming referred to above.

In case of additional requirements, exceptions and/or contradictions between the
Agreement and any Technical Specifications (as defined below) or GSM Association
Permanent Reference Documents, the provisions of the Agreement shall prevail.

All notices, information and communication required under the Agreement shall be
given as described in Annex C.1: Agreement Management Principles.

<PAGE>

AT&T WIRELESS SERVICES, INC.               AMERICAN CELLULAR CORPORATION

Having its principal place of              Having its principal place of
business:                                  business:

7277 164th Avenue NE                       14201 Wireless Way
Redmond WA 98052                           Oklahoma City, OK 73134



By: /s/ MARK BRADNER                       By: /s/ EVERETT R. DOBSON
   ----------------------------------         ----------------------------------
Name:                                      Name:
Title:                                     Title:




Date:  July 11, 2003                       Date:  July 11, 2003
     --------------------------------           --------------------------------



                                       2

<PAGE>

                                TABLE OF CONTENTS

<Table>
<Caption>
                                                                                                       Page
                                                                                                       ----
<S>                                                                                                    <C>
1.    Parties............................................................................................4

2.    Introduction.......................................................................................4

3.    Definitions........................................................................................4

4.    Annexes............................................................................................6

5.    Scope of the Agreement.............................................................................6

6.    Implementation of the network and services.........................................................7

7.    Modifications......................................................................................7

8.    Charging, Billing and Accounting...................................................................8

9.    Customer Care.....................................................................................12

10.      Confidentiality................................................................................12

11.      Data Privacy...................................................................................13

12.      Fraud Prevention...............................................................................13

13.      Liability of the Parties.......................................................................14

14.      Suspension of Services.........................................................................14

15.      Force Majeure..................................................................................15

16.      Duration of the Agreement......................................................................15

17.      Termination of the Agreement...................................................................16

18.      Changes to the Agreement, Annexes and Addenda..................................................16

19.      Miscellaneous..................................................................................17

20.      Choice of Law..................................................................................18

21.      Dispute Resolution & Arbitration...............................................................18
</Table>



                                       3
<PAGE>


1. PARTIES

                  General Terms and Conditions for GSM Roaming apply for the
                  Parties who have signed the Roaming Agreement

2. INTRODUCTION

2.1               The Parties have expressed their wish to make a bilateral
                  agreement for the establishment of Roaming Services between
                  their GSM/GPRS networks and it is therefore agreed as follows:

3. DEFINITIONS

                  For the purpose of the Agreement the following terms shall
         have the meanings set forth in their respective definitions, unless a
         different meaning is specified in another provision in the Agreement:

                  "3GPP" shall mean the Third Generation Partnership Project.

                  * is defined in Section 5.2 of the GSM Operating Agreement, it
                  being understood that such * may not be reciprocal, i.e. the
                  tariffs for GSM and GPRS Roaming charged by the applicable
                  VPMN Operator may be different.

                  "EDGE" shall mean Enhanced Data for GSM Evolution, a wireless
                  communications technology based on GSM and defined by the
                  relevant ETSI or 3GPP standards.

                  "ETSI" shall mean the European Telecommunications
                  Standardisation Institute.

                  "GPRS Roaming" shall mean General Packet Radio Service
                  Roaming, providing packet mode transmission between PMNs and
                  interworking with external network, including GPRS Roaming
                  using EDGE. GPRS Roaming allows the service subscriber to send
                  and receive data in an end-to-end packet transfer mode,
                  without utilizing network resources in circuit switched mode,
                  outside of their HPMN.

                  "GSM" shall mean Global System for Mobile communications, a
                  wireless communications technology defined by the relevant
                  ETSI or 3GPP standards.

                  "GSM Association Permanent Reference Documents" shall mean the
                  documents that are established, recognized and classified as
                  binding by the GSM Association Plenary.

                  "GSM Association Plenary" shall mean the group of appointed
                  representatives of the Signatories of the GSM Association.

         * Confidential information has been omitted and filed separately with
         the Securities and Exchange Commission.

                                       4
<PAGE>

                  "GSM Operating Agreement" shall mean the GSM Operating
                  Agreement of even date herewith between the Parties.

                  "GSM Roaming" shall mean GSM Roaming which means providing
                  circuit mode and packet mode transmission between PMNs. GSM
                  Roaming allows the service subscriber to send and receive data
                  in an end-to-end packet transfer mode outside their HPMN and
                  also make circuit switched connections, such as voice calls.

                  "HPMN" shall mean home public mobile network.

                  "HPMN Operator" shall mean a Party who is providing Services
                  to its subscribers in a geographic area where it holds a
                  license or has a legal right to establish and operate a GSM
                  network.

                  "Memorandum of Understanding of GSM Association" shall mean
                  the agreement signed by the Network Operators and/or
                  Authorities on 7th September 1987 and the Addendum to the
                  Memorandum of Understanding dated 24th September 1991.

                  "MOU" shall mean a minute of use.

                  "Offering Memorandum" means the Offering Memorandum,
                  Solicitation of Consents and Votes, Plan of Reorganization,
                  Disclosure Statement and Ballot issued by ACC and DCC on July
                  14, 2003.

                  "Party" shall mean a signatory hereto.

                  "PDP" shall mean Packet Data Protocol.

                  "Person" shall mean an individual, corporation, limited
                  liability company, partnership or other legal entity.

                  "PMN" shall mean a public mobile network.

                  "PMN Operator" shall mean a Person operating a PMN.

                  "Restructuring" is defined in the Offering Memorandum.

                  "Roaming Subscriber" shall mean a Person with valid
                  subscription for use issued by one of the Parties and using a
                  GSM SIM (Subscriber Identity Module) and/or a GSM USIM
                  (Universal Subscriber Identity Module) who seeks GSM
                  service(s) in a geographic area outside the area served by its
                  HPMN Operator.

                  "Roaming" shall mean use of the network of the VPMN Operator
                  by the subscribers of the HPMN Operator, which shall include
                  GSM Roaming and GPRS Roaming.

                  "Services" shall mean the services for Roaming as agreed upon
                  by the Parties in AA.14 and may include:



                                       5
<PAGE>

                           o        Circuit Switched based services, hereinafter
                                    called "CS" as specified in AA.14, Annex
                                    1.2, article I.2.1; and/or

                           o        Packet Switched based services, hereinafter
                                    called "GPRS" as specified in AA.14, Annex
                                    1.2, article I.2.2

                  "Session" shall mean the time between PDP Context activation
                  until PDP Context deactivation.

                  "SMS" shall mean short alphanumeric messages up to 160
                  characters in length utilizing the digital control channel.

                  A "Subsidiary" of a Party means any other Person directly or
                  indirectly owned or controlled by the Party, for so long as
                  such ownership or control lasts. Ownership or control shall
                  exist through the direct or indirect ownership of more than
                  50% of the nominal value of the issued equity share capital or
                  of more than 50% of the shares entitling the holders to vote
                  for the election of directors or Persons performing similar
                  functions.

                  "TAP" shall mean Transferred Account Procedure as defined and
                  described in GSM Association Permanent Reference Documents.

                  "Technical Specifications" shall mean the technical
                  specifications defined and adopted by 3GPP (Third Generation
                  Partnership Project), including the ETSI technical
                  specifications defined and adopted by 3GPP.

                  "VPMN" shall mean a visiting public mobile network.

                  "VPMN Operator" shall mean a Party who allows Roaming
                  Subscribers to use its GSM network(s).

4. ANNEXES

                  The Annexes are divided as set out in the Overview of the
                  Annex Structure, in Common Annexes and in 2 sets of individual
                  Annexes; one set for each Party.

5. SCOPE OF THE AGREEMENT

5.1               In respect of and subject to their licenses or rights and
                  other national binding regulations to establish and operate
                  GSM networks, the Parties to the Agreement agree to establish
                  Roaming between the GSM/GPRS network(s) owned and operated by
                  themselves and their respective Subsidiaries in accordance
                  with relevant Technical Specifications and GSM Association
                  Permanent Reference Documents, including all the commercial
                  aspects, as defined in the Annexes hereto or as may be amended
                  from time to time in accordance with the terms of the
                  Agreement.



                                       6
<PAGE>

5.2               Additional requirements and exceptions to the Technical
                  Specifications and GSM Association Permanent Reference
                  Documents, as agreed between the Parties, are detailed in the
                  Annexes to the Agreement or as may be amended from time to
                  time in accordance with the terms of the Agreement.

6. IMPLEMENTATION OF THE NETWORK AND SERVICES

6.1               Network Implementation

                  The Parties agree to comply in all material respects with the
                  relevant requirements and procedures of the GSM Association
                  Permanent Reference Documents agreed by the GSM Association
                  from time to time and as amended by the GSM Association from
                  time to time.

6.2               Services

             6.2.1    The Services provided by each Party are defined in
                      Annex I.2 as may be amended from time to time.

             6.2.2    The Services made available to individual Roaming
                      Subscribers shall only be those for which the Roaming
                      Subscribers have valid subscriptions in their HPMN.

             6.2.3    Both Parties agree that their Subscribers, while Roaming,
                      may experience conditions of service different from the
                      conditions in their HPMN.

             6.2.4    The Parties shall use reasonable best efforts to complete,
                      as soon as practicable, all test procedures necessary in
                      order to enable the Parties to provide Services hereunder.

7. MODIFICATIONS

7.1               Nothing in this Agreement shall limit either Party's right to
                  implement new Services or change its existing Services as it
                  sees fit. Each Party agrees to use its best efforts to give
                  the other Party at least four (4) weeks written notice of any
                  major change which has an impact on Roaming.

7.2               Following such notice of change both Parties agree to discuss
                  the impact of any such change for Roaming Subscribers,
                  including Roaming Subscribers' access to these Services, and
                  the necessary actions to be performed, e.g. testing or
                  administrative activities.



                                       7
<PAGE>

8. CHARGING, BILLING AND ACCOUNTING

8.1               Charging and tariffs

             8.1.1    Both Parties agree that when a Roaming Subscriber
                      uses the Services of the VPMN Operator, the Roaming
                      Subscriber's HPMN Operator shall be responsible for
                      payment of charges for the Services so used in
                      accordance with the tariffs of the VPMN Operator
                      stated in Annex I.3.1. Notwithstanding the foregoing,
                      the Parties agree that, for the duration of this
                      Agreement, and not subject to change pursuant to
                      Article 8.1.3 below, the VPMN Operator tariffs for
                      domestic GSM and GPRS Roaming shall be determined in
                      accordance with the provisions of this Section 8.1.1.

         (a)      Rates for Contract Years 1-3

                  (i) Table Rates. The VPMN Operator tariffs for domestic GSM
         and GPRS Roaming for the first three Contract Years shall be the rates
         set forth opposite such Contract Years in the table below ("Table
         Rates"). "Contract Years" means the five consecutive annual periods
         commencing on the date hereof.

<Table>
<Caption>
                                                                                            SMS
                                                                                          Rate per
                                                         GSM Rate     GPRS/EDGE Rate      Message
           Contract Year            Period               per MOU       per Kilobyte     Originated*
           -------------       ----------------          -------      --------------    -----------
<S>                            <C>                       <C>          <C>               <C>
                 1             7/1/03 - 6/30/04             *                *               *
                 2             7/1/04 - 6/30/05             *                *               *
                 3             7/1/05 - 6/30/06             *                *               *
                 4             7/1/06 - 6/30/07             *                *               *
                 5             7/1/07 - 6/30/08             *                *               *
</Table>

*        Includes TDMA, GSM, GPRS, EDGE. No charge for messages terminated. Rate
subject to adjustment in accordance with Section 8.1.1(g).


------------
* Confidential information has been omitted and filed separately with the
Securities and Exchange Commission



                                       8
<PAGE>

         (b)      Rates for Contract Years 4-5

                  (i) Negotiated Rates. At any time during the third quarter of
         Contract Year 3, if the Parties have not adopted *, ACC may (but shall
         not be obligated to) initiate, by notice to AWS, a 30-day period of
         roaming rate and exclusivity negotiations, provided, that such 30-day
         period must be commenced and completed within the third quarter of
         Contract Year 3. If negotiations are initiated by ACC, both Parties
         will negotiate in good faith to seek to agree on fair and reasonable
         GSM and GPRS roaming rates and exclusivity provisions for Contract
         Years 4 and 5.

                  (ii) Formula Rates. If ACC initiates the negotiation
         contemplated in clause (b)(i) and the Parties do not agree on GSM and
         GPRS roaming rates and exclusivity provisions for Contract Years 4 and
         5 during the aforementioned 30-day period, AWS will deliver to ACC,
         within 30 days following the end of the third quarter of Contract Year
         3, its calculation of the Formula Rates for the 12-month period ending
         at the end of the third quarter of Contract Year 3. Within ten business
         days after receipt of such calculation, ACC will notify AWS whether it
         elects to have such Formula Rates (or, if lower, the Table Rates for
         Contract Year 4) apply to Contract Year 4. If ACC so elects, then (x)
         the Formula Rates (as set forth in the aforementioned calculation) or,
         if lower, the Table Rates for Contract Year 4 will apply to Contract
         Year 4, (y) the Formula Rates (as determined pursuant to the
         definitions of ARPMin and ARPByte) or, if lower, the Table Rates for
         Contract Year 5 will apply to Contract Year 5 and (z) the exclusivity
         obligations of AWS under Article 4 of the GSM Operating Agreement will
         continue in effect during Contract Years 4 and 5, subject to the terms
         and conditions of the GSM Operating Agreement.

                  (iii) Table Rates. If either (x) ACC does not initiate
         negotiations pursuant to Section 8.1.1(b)(i) or (y) ACC initiates the
         negotiation of rates and exclusivity, the Parties are unable to agree
         upon new rates or exclusivity, and ACC elects not to apply the Formula
         Rates (or, if lower, the Table Rates for Contract Year 4) to Contract
         Year 4 (or fails to make a timely election), then (A) the Table Rates
         for Contract Year 3 * will apply to Contract Years 4 and 5 and (B) if
         the Parties have not adopted *, the obligations of AWS under Section 4
         of the GSM Operating Agreement will terminate at the end of Contract
         Year 3.


------------
* Confidential information has been omitted and filed separately with the
Securities and Exchange Commission



                                       9
<PAGE>
                  (iv) *.

         (c) Rates after Contract Year 5. If the Term of the Agreement is
extended for any period after Contract Year 5 pursuant to Section 5.2 of the GSM
Operating Agreement, the VPMN Operator tariffs for domestic GSM and GPRS Roaming
for such period will be *.

         (d) Voice over Internet Protocol. Once Voice over Internet Protocol
("VoIP") is implemented in the ACC GSM Systems (as defined in the GSM Operating
Agreement), voice traffic utilizing this technology will be measured in
kilobytes, and accordingly it will be necessary to convert kilobytes into voice
MOUs for billing purposes. Unless a more accurate equivalent is available at the
time of VoIP implementation, the following kilobytes per voice MOU equivalent
shall be used unless the Parties otherwise agree. Prior to implementation of the
Adaptive Multi-Rate ("AMR") codec, 720 kilobytes per MOU equivalent shall be
used for billing purposes. After the implementation of the AMR codec, 300
kilobytes per MOU equivalent shall be used for billing purposes. The Parties
shall implement the AMR codec in their respective GSM Systems (as defined in the
GSM Operating Agreement) as soon as commercially practicable, and shall use
commercially reasonable efforts to adopt improved speech codecs as and when they
become generally available on commercially reasonable terms.

         (e)      Definitions

                  "ARPByte" means, with respect to any 12-month period, a rate
         per minute calculated by dividing AWS GPRS and succeeding data
         technology revenue for the immediately preceding 12-month period by AWS
         billed kilobytes for the immediately preceding 12-month period. For
         purposes of this definition, AWS GPRS and succeeding data technology
         revenue includes home revenue and incollect revenue from GPRS and
         succeeding data technologies (including but not limited to EDGE and
         UMTS) but excludes outcollect revenue and equipment revenue; and AWS
         billed kilobytes includes home kilobytes and incollect kilobytes from
         GPRS and succeeding data technologies (including but not limited to
         EDGE and UMTS).

                  "ARPMin" means, with respect to any 12-month period, a rate
         per minute calculated by dividing AWS gross revenue for the immediately
         preceding 12-month period by AWS billed minutes for the immediately

* Confidential information has been omitted and filed separately with the
  Securities and Exchange Commission.


                                       10
<PAGE>

         preceding 12-month period. For purposes of such definition, AWS gross
         revenue includes all AWS revenue except outcollect revenue and
         equipment revenue; and AWS billed minutes includes all home MOUs and
         incollect MOUs.

                   "Formula Rate" means (i) with respect to GPRS Roaming, a rate
         per kilobyte equal to *, and (ii) with respect to GSM Roaming, a rate
         per minute equal to *

         (f) Quarterly Reports. From the beginning of Contract Year 2 until the
end of Contract Year 3, if ACC so requests, AWS will deliver to ACC, on a
quarterly basis, reports setting forth the components of the calculation of its
monthly ARPMin and ARPByte rates.

         (g) SMS Arrangements. The SMS rate will be *per message originated;
provided, that if the parties are able to connect their SMS networks directly,
the SMS rate will be *per message originated. The parties will use commercially
reasonable efforts to connect their SMS networks directly.

         8.1.2    However, the HPMN Operator shall not be liable for the payment
                  of charges for chargeable Services provided by the VPMN
                  Operator without Subscriber Identity Authentication as defined
                  in GSM Association Permanent Reference Documents, except to
                  the extent that the HPMN Operator actually recovers all
                  charges due in relation to the Roaming Subscriber. In the case
                  of re-authentication malfunction, procedures are further
                  detailed in Annex I.5.2.

         8.1.3    Notwithstanding Article 18.1 either Party shall have the right
                  to vary its tariff stated in the Annex I.3.1 or subsequent
                  variation thereof, other than those set forth in 8.1.1 above.
                  In the case of scheduled changes (as described in BA.27) a
                  Party shall give 60 days written notice of any variation to
                  its tariff and the new change shall take effect on the first
                  day of the month following the expiration of the 60 day notice
                  period. In the case of unscheduled changes (as described in
                  BA.27) a Party shall use all reasonable endeavours to give
                  adequate notice of such changes and the new change shall take
                  effect on the first day following the expiration of the notice
                  period given. Any variation in the tariff shall be deemed to
                  be incorporated into the Agreement.

8.2           Implementation of TAP

------------
* Confidential information has been omitted and filed separately with the
Securities and Exchange Commission



                                       11
<PAGE>

                  The implementation of TAP shall be done according to the GSM
                  Association Permanent Reference Documents and the provisions
                  set out in the Annex C.3.1.

8.3               Billing and Accounting

                  The implementation of billing and accounting shall be done
                  according to the GSM Association Permanent Reference Documents
                  and the provisions set out in Annex C.3.2 as amended from time
                  to time or where there is a differing accounting practice or
                  regulations in the U.S., the U.S. practice or regulations
                  shall prevail.

9. CUSTOMER CARE

                  The responsibilities of each Party concerning Customer Care
                  are described in Annex C.4.

10. CONFIDENTIALITY

10.1              The Parties agree that all aspects of the contents of the
                  Agreement shall be treated as confidential and that no
                  information in respect of the content of the Agreement shall
                  be disclosed without the prior written consent of both of the
                  Parties except (i) as required by law or legal process, (ii)
                  to a Party's employees who need to know same and such Party's
                  attorneys, advisors, representatives, agents, lenders,
                  insurers, and current or potential investors (collectively,
                  "its Representatives"), (iii) in the Offering Memorandum and
                  such other disclosure documents as, in the good faith judgment
                  of DCC's outside legal counsel, are necessary to effect the
                  Restructuring ("Reorganization Disclosure") and (iv) as
                  necessary to implement the Agreement and inform customers.

10.2              The Parties hereby agree to treat all information exchanged
                  between them in connection with the Agreement (hereinafter
                  referred to as "Information") as confidential and agree not to
                  disclose such Information in any manner whatsoever, in whole
                  or in part except as provided in this Article 10. The other
                  Party shall not use any Information other than in connection
                  with (i) the discussions between them and any transactions
                  resulting therefrom, (ii) for the purpose of obtaining funds
                  or insurance or in connection with any bona fide business
                  transaction, in which case the disclosing Party shall advise
                  the lenders or insurance companies of such Party's
                  confidentiality obligation under this Article 10 before
                  disclosing the Information and (iii) Reorganization
                  Disclosure. Each Party shall be liable in accordance with
                  Article 13 to the other Party in respect of any unauthorized
                  disclosure of



                                       12
<PAGE>

                  Information made by its Representatives to whom it has
                  disclosed Information.

10.3              In addition to the above, Information may be transmitted to
                  governmental, judicial or regulatory authorities, as may be
                  required by any governmental, judicial or regulatory
                  authority, provided, that the Party transmitting such
                  Information gives the other Party reasonable notice and
                  opportunity to seek confidential treatment of such Information
                  by any such authority.

10.4              For the purposes of the Agreement, Information shall not be
                  considered to be confidential if such Information is:

                  a)       in or passed into the public domain other than by
                           breach of this Article;

                  b)       known to a receiving Party prior to the disclosure by
                           a disclosing Party;

                  c)       disclosed to a receiving Party without restriction by
                           a third Party having the full right to disclose; or

                  d)       independently developed by a receiving Party to whom
                           no disclosure of confidential Information relevant to
                           such Information has been made.

10.5              Article 10 shall survive the termination of the Agreement for
                  a period of two years.

11. DATA PRIVACY

11.1              Each Party's obligations hereunder to transfer Information to
                  the other Party shall not apply to the extent that a Party is
                  prohibited from doing so by applicable regulations and laws
                  applicable to Roaming and/or data protection.

11.2              The Parties confirm that they shall comply with applicable
                  Data Privacy Regulations/Laws. Further Details of Data Privacy
                  aspects are given in Annexes C.6. and I.6.

12. FRAUD PREVENTION

                  The Parties shall co-operate in good faith regarding the
                  procedures concerning fraudulent or unauthorized use by
                  Roaming Subscribers. Details of Fraud Prevention procedures
                  are given in Annex C.7.



                                       13
<PAGE>

13. LIABILITY OF THE PARTIES

                  In no event shall either Party be liable for any consequential
                  damage or loss of whatsoever nature, including but not limited
                  to, loss of profit or loss of business.

14. SUSPENSION OF SERVICES

14.1              Suspension of Services to individual Roaming Subscribers or
                  all Roaming Subscribers

                  Notwithstanding anything in the Agreement to the contrary, the
                  VPMN Operator may without liability suspend or terminate all
                  or any of its Services to Roaming Subscriber(s) in
                  circumstances where it would suspend or terminate those
                  Services to its own subscribers, including but not limited to:

                  a)       subscribers using equipment which is defective or
                           illegal;

                  b)       subscribers causing any technical or other problems
                           on the VPMN Operator's network;

                  c)       suspected fraudulent or unauthorized use;

                  d)       authentication of the subscription not being
                           possible; or

                  e)       maintenance or enhancement of the network.

14.2              Suspension of Services to all Roaming Subscribers by VPMN
                  Operator

                  In case of a proposed suspension of Services to all Roaming
                  Subscribers, the VPMN Operator shall use its best efforts to
                  give four (4) weeks written notice to the other Party prior to
                  the suspension taking effect. If the suspension continues for
                  more than six (6) months, the other Party shall have the right
                  to terminate the Agreement by written notice.

14.3              Suspension of Services to all Roaming Subscribers by HPMN
                  Operator

                  The HPMN Operator has the right at any time, without
                  discriminating among operators and without liability, in the
                  event of suspected fraudulent or unauthorized use of the VPMN
                  network, by giving reasoned written notice to the VPMN
                  Operator, to suspend access to the VPMN Services for its own
                  subscribers Roaming in the VPMN, or if it is technically more
                  practicable, to require that the



                                       14
<PAGE>

                  VPMN Operator takes actions to suspend all of its Services to
                  Roaming Subscribers of the HPMN Operator. The VPMN Operator
                  shall use its best efforts to comply with such requirement
                  within five (5) working days after receipt of the notice.

                  The suspension shall be removed as soon as the reason for the
                  suspension has been overcome by the VPMN Operator to the
                  reasonable satisfaction of the HPMN Operator.

15. FORCE MAJEURE

15.1              Non-performance or defective performance of either Party's
                  obligations pursuant to the Agreement or delay in performing
                  same shall not constitute a breach of the Agreement to the
                  extent, and for as long as, it is due to reasons outside such
                  Party's control (in each case a "Force Majeure Event"),
                  including, but not being limited to, governmental action, or
                  requirement of regulatory authority, acts of God, terrorism,
                  riots, revolution, lockouts, strikes, shortage of
                  transportation, war, rebellion or other military action, fire,
                  flood, explosion, sabotage, nuclear incidents, earthquakes,
                  lightning, storms, sinkholes, epidemics, delays or
                  non-performance of suppliers or subcontractors, natural
                  catastrophes, or any other unforeseeable obstacles that a
                  Party is not able to overcome with reasonable efforts. The
                  Party prevented from fulfilling its obligations shall on
                  becoming aware of such Force Majeure Event inform the other
                  Party in writing of such Force Majeure Event as soon as
                  possible. If the Force Majeure Event continues for more than
                  six (6) consecutive months, either Party shall have the right
                  to terminate the Agreement with immediate effect by written
                  notice.

15.2              If the affected Party fails to inform the other Party of the
                  occurrence of a Force Majeure Event in accordance with Article
                  15.1 above, then such Party thereafter shall not be entitled
                  to refer to such event as force majeure as a reason for
                  non-fulfillment, to the extent such Party is disadvantaged by
                  such delay. This obligation does not apply if the Force
                  Majeure Event is known by both Parties or the affected Party
                  is unable to inform the other Party due to the Force Majeure
                  Event.

16. DURATION OF THE AGREEMENT

                  The term of the Agreement (the "Term") shall commence on the
                  date hereof and, unless the Agreement shall have earlier
                  terminated in accordance with Section 17.1, shall expire on
                  the fifth anniversary of the date hereof, subject to Section
                  5.2 of the GSM Operating Agreement.



                                       15
<PAGE>

17. TERMINATION OF THE AGREEMENT

17.1              In addition to the provisions of Article 16, the Agreement may
                  be terminated as follows:

                  a)       by mutual agreement of the Parties;

                  b)       by one of the Parties, with immediate effect, when
                           the other Party is in material breach of the
                           Agreement and does not remedy, such breach within
                           thirty (30) days of receipt of a written notice to
                           such effect;

                  c)       by one of the Parties, with immediate effect, if the
                           other Party becomes bankrupt or insolvent or enters
                           into any composition or arrangement with its
                           creditors, except in accordance with the plan of
                           reorganization of ACC contemplated by the Offering
                           Memorandum, and that other Party is not able to
                           ensure performance of its monetary obligations under
                           the Agreement by a guarantee from a first class bank,
                           payable on first written demand;

                  d)       by written notice of either Party to the other in the
                           event that Roaming becomes technically or
                           commercially impracticable on either Party's network
                           and the provisions set out in Article 14 are not
                           sufficient to solve the problem or if an unacceptable
                           level of unauthorized use occurs and the other Party
                           is not capable of remedying such unauthorized use to
                           normal levels within sixty (60) days of receipt of a
                           written notice to such effect; or

                  e)       subject to Article 19.1 by one of the Parties, with
                           immediate effect and as to the affected licensed area
                           only, in the event a final order by the relevant
                           governmental authority revoking or denying renewal of
                           the GSM license(s) or permission to operate a GSM
                           network(s) granted to the other Party, or any other
                           license necessary to operate the GSM Service(s),
                           takes effect.

18. CHANGES TO THE AGREEMENT, ANNEXES AND ADDENDA

18.1              Any amendments and/or additions to the Agreement and/or
                  Annexes and/or Addenda shall be valid only if made in writing
                  and signed by duly authorized representatives of both Parties
                  hereto.

18.2              It is also recognized by the Parties that it may be
                  appropriate to seek changes to the Agreement in the light of
                  experience and development in the GSM Association and the
                  establishment of Roaming between the Parties. Accordingly, in
                  such event the Parties shall enter into good faith discussions
                  with a view to agreeing mutually acceptable modifications to
                  the Agreement.



                                       16
<PAGE>

                  Without limiting the generality of the foregoing, the Parties
                  agree to modify the Agreement as contemplated by Section
                  5.2(a) of the GSM Operating Agreement.

19. MISCELLANEOUS

19.1              Entire Agreement

                  The Agreement and the GSM Operating Agreement, together with
                  any annexes, schedules and exhibits hereto and thereto,
                  contain the entire agreement and understanding of the Parties
                  relating to the subject matter hereof and thereof, and
                  supersede all prior negotiations, proposals, offers,
                  agreements and understandings (written or oral) relating to
                  such subject matter.

19.2              Successors and Assigns

                  The Agreement and the rights and obligations specified herein
                  shall be binding upon the Parties hereto and their respective
                  permitted successors and permitted assigns, and neither Party
                  shall sell, transfer or assign the Agreement or any part,
                  interest, right or obligation hereunder, including by
                  operation of law, except that a Party shall have the right to
                  transfer or assign the Agreement in whole (but not in part) to
                  a Subsidiary who is also the Signatory to the GSM Association
                  and ACC shall have the right to transfer or assign the
                  Agreement in whole to a Subsidiary of Dobson Communications
                  Corporation that directly or indirectly owns, operates and
                  controls wireless communications systems in the ACC Markets
                  (as defined in the GSM Operating Agreement) and does not own,
                  manage, operate or control any other wireless communications
                  systems, provided, that such assignee expressly assumes, by
                  written instrument approved by the Parties, all of the
                  obligations of such Party hereunder and thereby becomes a
                  Party hereunder, it being understood that such assignment
                  shall not release the assigning Party of its obligations under
                  Article 10 of this Agreement. No person other than a Party to
                  the Agreement shall acquire any rights hereunder as a
                  third-party beneficiary or otherwise by virtue of the
                  Agreement.

19.3              Headings

                  The headings of the Agreement are for the convenience of
                  reference only and shall in no way limit or affect the meaning
                  or interpretation of the provisions of the Agreement.

19.4              No waiver



                                       17
<PAGE>

                  Failure by any Party at any time or times to require
                  performance of any provisions of the Agreement shall in no
                  manner affect its rights to enforce the same, and the waiver
                  by any Party of any breach of any provisions of the Agreement
                  shall not be construed to be a waiver by such Party of any
                  succeeding breach of such provision or waiver by such Party of
                  any breach of any other provision hereof.

19.5              Provisions severable

                  If any part of the Agreement is held to be invalid or
                  unenforceable, such determination shall not invalidate any
                  other provision of the Agreement; and the Parties shall
                  attempt, through negotiations in good faith, to replace any
                  part of the Agreement so held to be invalid or unenforceable.
                  The failure of the Parties to agree on such replacement shall
                  not affect the validity of the remaining parts of the
                  Agreement.

20. CHOICE OF LAW

                  The Agreement and any matters relating hereto shall be
                  governed by and construed in accordance with the internal laws
                  of the State of Delaware.

21. DISPUTE RESOLUTION & ARBITRATION

21.1              If a dispute arises out of or relating to this Agreement, or
                  the transactions contemplated hereby, or the construction,
                  interpretation, performance, breach, termination,
                  enforceability or validity thereof, whether such claim is
                  based on rights, privileges or interests recognized by or
                  based upon contract, tort, fraud, misrepresentation, statute,
                  common law or any other legal or equitable theory, and whether
                  such claim existed prior to or arises on or after the date
                  hereof (a "Dispute"), the dispute resolution processes set
                  forth in this Article 21 shall govern the resolution of such
                  dispute.

21.2              If a Dispute cannot be resolved by the executives having
                  primary managerial responsibility for the matter to which the
                  Dispute pertains, the Parties shall attempt in good faith to
                  resolve such Dispute promptly by negotiation between
                  executives who have authority to settle the Dispute and who
                  are at the level of the executives who have negotiated this
                  Agreement ("Senior Party Representatives").

21.3              A Party may provide any other Party notice (a "Dispute
                  Notice") of any Dispute that has not been resolved in the
                  normal course of business. Within ten business days after
                  delivery of the Dispute



                                       18
<PAGE>

                  Notice, the receiving Party shall submit to each other Party a
                  response (the "Response"). The Dispute Notice and the Response
                  shall each include (a) a statement setting forth the position
                  of the Party providing such notice and a summary of arguments
                  supporting such position, and (b) the name and title of such
                  Party's Senior Party Representative and any other Persons who
                  will accompany the Senior Party Representative at the meeting
                  at which the Parties will attempt to settle the Dispute.
                  Within 30 business days after delivery of the Dispute Notice,
                  the Senior Party Representatives of the Parties shall meet at
                  a mutually acceptable time and place, and thereafter as often
                  as they reasonably deem necessary, to attempt to resolve the
                  Dispute. All reasonable requests for information made by one
                  Party to another will be honored.

21.4              If the Dispute has not been resolved within 50 business days
                  after delivery of the Dispute Notice, or if the Parties fail
                  to meet within 30 business days after delivery of the Dispute
                  Notice, any Party may initiate arbitration of the Dispute as
                  provided below. If no Party initiates arbitration within 60
                  business days after delivery of the Dispute Notice, then the
                  Parties shall automatically be released from any and all
                  liability for the Dispute.

21.5              All negotiations pursuant to this section shall be treated as
                  compromise and settlement negotiations. Nothing said or
                  disclosed, nor any document produced, in the course of such
                  negotiations that is not otherwise independently discoverable
                  shall be offered or received as evidence or used for
                  impeachment or for any other purpose in any current or future
                  arbitration. The Parties agree that all communications and
                  negotiations between the Parties during the dispute resolution
                  process, any settlements agreed upon during the dispute
                  resolution process and any information regarding the other
                  Party obtained during the dispute resolution process (that are
                  not already public knowledge) are confidential and may be
                  disclosed only to employees and agents of the Parties who
                  shall have a "need to know" the information and who shall have
                  been made aware of the confidentiality obligations set forth
                  in this Article 21, unless the Party is required by law to
                  disclose such information.

21.6              If the Dispute is not resolved as provided in Sections 21.2
                  through 21.4 above, then any Party may initiate arbitration
                  proceedings by providing each other Party notice of such
                  initiation of arbitration. The Dispute shall then be settled
                  by arbitration in accordance with the CPR Non-Administered
                  Arbitration Rules in effect on the date hereof, by a panel of
                  three arbitrators. Each Party shall select one



                                       19
<PAGE>

                  of the three arbitrators and the two arbitrators so chosen
                  shall select the third arbitrator. The arbitrators shall be
                  governed by the United States Arbitration Act, 9 U.S.C.
                  Sections 1-16, and judgment upon the award rendered by the
                  arbitrators may be entered by any court having jurisdiction
                  thereof. The place of arbitration shall be chosen by the three
                  arbitrators. The arbitrators shall not order pre-hearing
                  discovery of documents or the taking of depositions, although
                  the arbitrators may compel the attendance of witnesses and the
                  production of documents at the hearing to the extent permitted
                  by the CPR Non-Administered Arbitration Rules.

21.7              If a Party does not provide a Dispute Notice within one year
                  following the time the Party first knows of the existence of
                  the acts or omissions that give rise to the Dispute, the Party
                  shall be forever estopped from asserting the Dispute against
                  any other Party.

21.8              The reasonable out-of-pocket costs (including reasonable
                  attorneys' fees and expenses) of the prevailing Party and the
                  fees of the arbitrators in any arbitration proceeding pursuant
                  to this Article 21 shall be paid by the other Party. The
                  arbitrators shall determine which Party is the prevailing
                  Party for purposes of this paragraph, and shall include such
                  determination in their award. If the arbitrators determine
                  that neither Party is the prevailing Party for purposes of
                  this paragraph, then each Party shall bear its own costs and
                  expenses, including attorneys' fees and expenses, and the
                  Parties shall share equally the fees of the arbitrators.

21.9              Notwithstanding the foregoing, nothing in this Agreement shall
                  preclude the Parties from seeking injunctive or other
                  equitable relief from a court with regard to any breach of
                  this Agreement.



                                       20
<PAGE>


OVERVIEW OF THE ANNEX STRUCTURE

COMMON ANNEXES:

<Table>
<Caption>
ANNEX NO.                          ANNEX NAME
---------                          ----------
<S>                                <C>
ANNEX C.1                          Agreement Management Principles
ANNEX C.2                          Services
ANNEX C.3                          Billing and Accounting
         ANNEX C.3.1               Information on Billing Data
         ANNEX C.3.2               Settlement Procedure
ANNEX C.4                          Customer Care Principles
ANNEX C.5                          Technical Aspects
         ANNEX C.5.1               Testing
         ANNEX C.5.2               Security
         ANNEX C.5.3               Information on Signalling Interconnection and / or
                                      IP Connectivity
ANNEX C.6                          Data Privacy, General Principles
ANNEX C.7                          Fraud Prevention Procedures
ANNEX C.8                          Additional annexes (optional)
</Table>



                                       21
<PAGE>

INDIVIDUAL ANNEXES:

<Table>
<Caption>
                         AWS                                                    ACC
------------------------------------------------------  -----------------------------------------------------
ANNEX I                      ANNEX NAME                 ANNEX I                    ANNEX NAME
SECTION NO.:                                            SECTION NO.:
--------------------------   -------------------------  -----------------------    --------------------------
<S>                          <C>                        <C>                        <C>
0                            REVISION SHEET             0                          REVISION SHEET

1                            AGREEMENT MANAGEMENT       1                          AGREEMENT MANAGEMENT
                             PRINCIPLES                                            PRINCIPLES

1.1                          Contact Points for         1.1                        Contact Points for
                             Agreement Management                                  Agreement Management

2                            SERVICES                   2                          SERVICES

2.1                          GSM services and GPRS PS   2.1                        GSM services and GPRS PS
                             Capabilities provided                                 Capabilities provided
                             for Roaming Subscribers                               for Roaming Subscribers

2.2                          Additional Services        2.2                        Additional Services
                             provided for Roaming                                  provided for Roaming
                             Subscribers                                           Subscribers

2.3                          SMS Interworking Services  2.3                        SMS Interworking Services

2.4                          GPRS PS Services and       2.4                        GPRS PS Services and
                             Applications                                          Applications

3                            BILLING AND ACCOUNTING     3                          BILLING AND ACCOUNTING

3.1                          GSM  Roaming Tariffs       3.1                        GSM  Roaming Tariffs

3.2                          Mailing list for TAP       3.2                        Mailing list for TAP

3.3                          Mailing list for Inter     3.3                        Mailing list for Inter
                             PMN Invoices                                          PMN Invoices

3.4                          Application of VAT         3.4                        Application of VAT

4                            CUSTOMER CARE              4                          CUSTOMER CARE

4.1                          Inter Operator Customer    4.1                        Inter Operator Customer
                             Care Contact                                          Care Contact

4.2                          Customer Services Numbers  4.2                        Customer Services Numbers
</Table>



                                       22
<PAGE>

<Table>
<S>                          <C>                        <C>                        <C>
4.3                          Customer Care Contact      4.3                        Customer Care Contact
                             Numbers                                               Numbers

5                            TECHNICAL ASPECTS          5                          TECHNICAL ASPECTS

5.1                          Contact Points for         5.1                        Contact Points for
                             Handling Test SIM and/or                              Handling Test SIM and/or
                             USIM Cards                                            USIM Cards

5.2                          Security                   5.2                        Security

6                            DATA PRIVACY               6                          DATA PRIVACY

6.1                          National Requirements      6.1                        National Requirements
                             for Data Privacy                                      for Data Privacy

7                            FRAUD PREVENTION           7                          FRAUD PREVENTION
                             PROCEDURES                                            PROCEDURES

7.1                          Information on Fraud       7.1                        Information on Fraud
                             Prevention Procedures                                 Prevention Procedures

8 ...                        ADDITIONAL ANNEXES         8 ...                      ADDITIONAL ANNEXES
                             (OPTIONAL)                                            (OPTIONAL)
</Table>


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