<PAGE>

                                                                   Exhibit 10.21

                           INTERCONNECTION AGREEMENT
                                    BETWEEN
                       BELLSOUTH TELECOMMUNICATIONS INC.
                                      AND
               MEBTEL INTEGRATED COMMUNICATIONS SOLUTIONS, LLC,
                   D/B/A INTEGRATED COMMUNICATIONS SOLUTIONS

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                               TABLE OF CONTENTS
                               -----------------

General Terms and Conditions
Part A
   1.  Purpose
   2.  Term of the Agreement
   3.  Ordering Procedures
   4.  Parity
   5.  White Pages Listings
   6.  Bona Fide Request/New Business Request Process for Further
       Unbundling
   7.  Liability and Indemnification
   8.  Intellectual Property Rights and Indemnification
   9.  Treatment of Proprietary and Confidential Information
  10.  Assignments
  11.  Resolution of Disputes
  12.  Taxes
  13.  Force Majeure
  14.  Year 2000 Compliance
  15.  Modification of Agreement
  16,  Waivers
  17.  Governing Law
  18.  Arm's Length Negotiations
  19.  Notices
  20.  Rule of Construction
  21.  Headings of No Force or Effect
  22.  Multiple Counterparts
  23.  Implementation of Agreement
  24.  Entire Agreement

Part B - Definitions

Attachment  1 - Resale
Attachment  2 - Unbundled Network Elements
Attachment  3 - Local Interconnection
Attachment  4 - Physical Collocation
Attachment  5 - Access to Numbers and Number Portability
Attachment  6 - Ordering and Provisioning
Attachment  7 - Billing and Billing Accuracy Certification
Attachment  8 - Rights-of-Way, Conduits and Pole Attachments
Attachment  9 - Bona Fide Request/New Business Request Process
Attachment 10 - Performance Measurements
Attachment 11 - Rates
Attachment 12 - Agreement Implementation Template
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                                           General Terms and Conditions - Part A
                                                                          Page 1

                                   AGREEMENT

     THIS AGREEMENT is made by and between BellSouth Telecommunications, Inc.,
("BellSouth"), a Georgia corporation, and Mebtel Integrated Communications
Solutions, LLC, d/b/a Integrated Communications Solutions ("ICS"), a Delaware
company, and shall be deemed effective as of December 18, 1998. This agreement
may refer to either BellSouth or ICS or both as a "Party" or "Parties.

                                  WITNESSETH

     WHEREAS, BellSouth is a local exchange telecommunications company
authorized to provide telecommunications services in the states of Alabama,
Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South
Carolina, and Tennessee; and

     WHEREAS, ICS is an alternative local exchange telecommunications company
("CLEC") authorized to provide telecommunications services in the states of
Alabama, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina,
South Carolina, and Tennessee; and

     WHEREAS, the Parties wish to interconnect their facilities, purchase
unbundled elements, and exchange traffic specifically for the purposes of
fulfilling their obligations pursuant to sections 251 and 252 of the
Telecommunications Act of 1996 ("the Act").

     NOW THEREFORE, in consideration of the mutual agreements contained herein,
BellSouth and ICS agree as follows:

1.        Purpose

          The Parties agree that the rates, terms and conditions contained
          within this Agreement, including all Attachments, comply and conform
          with each Parties' obligations under sections 251 and 252 of the Act.
          The access and interconnection obligations contained herein enable ICS
          to provide competing telephone exchange service to residential and
          business subscribers within the territory of BellSouth. The Parties
          agree that ICS will not be considered to have offered interconnection
          in any state within BellSouth's region until such time as it has
          ordered interconnection facilities for the purposes of providing
          business and/or residential local exchange service to customers.
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                                           General Terms and Conditions - Part A
                                                                          Page 2

2.        Term of the Agreement

2.1       The term of this Agreement shall be two years, beginning  December 18,
          1998.

2.2       The Parties agree that by no later than one hundred and eighty (180)
          days prior to the expiration of this Agreement, they shall commence
          negotiations with regard to the terms, conditions and prices of local
          interconnection to be effective beginning on the expiration date of
          this Agreement ("Subsequent Agreement"). The Parties further agree
          that any such Subsequent Agreement shall be for a term of no less than
          two (2) years unless the Parties agree otherwise.

2.3       If, within one hundred and thirty-five (135) days of commencing the
          negotiation referred to in Section 2.2, above, the Parties are unable
          to satisfactorily negotiate new local interconnection terms,
          conditions and prices, either Party may petition the Commission to
          establish appropriate local interconnection arrangements pursuant to
          47 U.S.C. 252. The Parties agree that, in such event, they shall
          encourage the Commission to issue its order regarding the appropriate
          local interconnection arrangements no later than the expiration date
          of this Agreement. The Parties further agree that in the event the
          Commission does not issue its order prior to the expiration date of
          this Agreement, or if the Parties continue beyond the expiration date
          of this Agreement to negotiate the local interconnection arrangements
          without Commission intervention, the terms, conditions and prices
          ultimately ordered by the Commission, or negotiated by the Parties,
          will be effective retroactive to the day following the expiration date
          of this Agreement. Until the Subsequent Agreement becomes effective,
          the Parties shall continue to exchange traffic pursuant to the terms
          and conditions of this Agreement.

3.        Ordering Procedures

3.1       ICS shall provide BellSouth its Carrier Identification Code (CIC),
          Operating Company Number (OCN), Group Access Code (GAC) and Access
          Customer Name and Address (ACNA) code prior to placing its first
          order.

3.2       Detailed procedures for ordering and provisioning BellSouth services
          are set forth in BellSouth's Local Interconnection and Facility Based
          Ordering Guide and Resale Ordering Guide, as appropriate.

3.3       BellSouth has developed electronic systems for placing most resale and
          some Unbundled Network Elements (UNE) orders. BellSouth has also
          developed electronic systems for accessing data needed to place orders
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                                           General Terms and Conditions - Part A
                                                                          Page 3

          including valid address, available services and features, available
          telephone numbers, due date estimation on pre-order and calculation on
          firm order, and customer service records where applicable. Charges for
          Operational Support Systems (OSS) shall be as set forth in this
          agreement in Exhibit A of Attachment 1 and in Attachment 11.

4.        Parity

          The services and service provisioning that BellSouth provides ICS for
          resale will be at least equal in quality to that provided to
          BellSouth, or any BellSouth subsidiary, affiliate or end user. In
          connection with resale, BellSouth will provide ICS with pre-ordering,
          ordering, maintenance and trouble reporting, and daily usage data
          functionality that will enable ICS to provide equivalent levels of
          customer service to their local exchange customers as BellSouth
          provides to its own end users. BellSouth shall also provide ICS with
          unbundled network elements, and access to those elements, that is at
          least equal in quality to that which BellSouth provides BellSouth, or
          any BellSouth subsidiary, affiliate or other CLEC. BellSouth will
          provide number portability to ICS and their customers with minimum
          impairment of functionality, quality, reliability and convenience.

5.        White Pages Listings

          BellSouth shall provide ICS and their customers access to white pages
          directory listings under the following terms:

5.1       Listings. BellSouth or its agent will include ICS residential and
          business customer listings in the appropriate White Pages (residential
          and business) or alphabetical directories. Directory listings will
          make no distinction between ICS and BellSouth subscribers.

5.2       Rates. Subscriber primary listing information in the White Pages shall
          be provided at no charge to ICS or its subscribers provided that ICS
          provides subscriber listing information to BellSouth at no charge.

5.3       Procedures for Submitting ICS Subscriber Information. BellSouth will
          provide to ICS a magnetic tape or computer disk containing the proper
          format for submitting subscriber listings. ICS will be required to
          provide BellSouth with directory listings and daily updates to those
          listings, including new, changed, and deleted listings, in an
          industry-accepted format. These procedures are detailed in BellSouth's
          Local Interconnection and Facility Based Ordering Guide.
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                                           General Terms and Conditions - Part A
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5.4       Unlisted Subscribers. ICS will be required to provide to BellSouth the
          names, addresses and telephone numbers of all ICS customers that wish
          to be omitted from directories.

5.5       Inclusion of ICS Customers in Directory Assistance Database. BellSouth
          will include and maintain ICS subscriber listings in BellSouth's
          directory assistance databases at no charge. BellSouth and ICS will
          formulate appropriate procedures regarding lead time, timeliness,
          format and content of listing information.

5.6       Listing Information Confidentiality. BellSouth will accord ICS's
          directory listing information the same level of confidentiality that
          BellSouth accords its own directory listing information, and BellSouth
          shall limit access to ICS's customer proprietary confidential
          directory information to those BellSouth employees who are involved in
          the preparation of listings.

5.7       Optional Listings. Additional listings and optional listings will be
          offered by BellSouth at tariffed rates as set forth in the General
          Subscriber Services Tariff.

5.8       Delivery. BellSouth or its agent shall deliver White Pages directories
          to ICS subscribers at no charge.

6.        Bona Fide Request/New Business Request Process for Futher Unbundling

          BellSouth shall, upon request of ICS, provide to ICS access to its
          unbundled elements at any technically feasible point for the provision
          of ICS's telecommunications service where such access is necessary and
          failure to provide access would impair the ability of ICS to provide
          services that it seeks to offer. Any request by ICS for access to an
          unbundled element that is not already available shall be treated as an
          unbundled element Bona Fide Request/New Business Request, and shall be
          submitted to BellSouth pursuant to the Bona Fide Request/New Business
          Request process set forth in Attachment 9.

7.        Liability and Indemnification

7.1       BellSouth Liability. BellSouth shall take financial responsibility for
          its own actions in causing, or its lack of action in preventing,
          unbillable or uncollectible ICS revenues.

7.2       Liability for Acts or Omissions of Third Parties. Neither BellSouth
          nor ICS shall be liable for any act or omission of another
          telecommunications
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                                           General Terms and Conditions - Part A
                                                                          Page 5

          company providing a portion of the services provided under this
          Agreement.

7.3       Limitation of Liability.

7.3.1     Each Party's liability to the other for any loss, cost, claim, injury
          or liability or expense, including reasonable attorney's fees relating
          to or arising out of any negligent act or omission in its performance
          of this Agreement whether in contract or in tort, shall be limited to
          a credit for the actual cost of the services or functions not
          performed or improperly performed.

7.3.2     Limitations in Tariffs. A Party may, in its sole discretion, provide
          in its tariffs and contracts with its Customer and third parties that
          relate to any service, product or function provided or contemplated
          under this Agreement, that to the maximum extent permitted by
          Applicable Law, such Party shall not be liable to Customer or third
          Party for (i) any Loss relating to or arising out of this Agreement,
          whether in contract, tort or otherwise, that exceeds the amount such
          party would have charged that applicable person for the service,
          product or function that gave rise to such Loss and (ii) Consequential
          Damages. To the extent that a Party elects not to place in its tariffs
          or contracts such limitations of liability, and the other Party incurs
          a Loss as a result thereof, such Party shall indemnify and reimburse
          the other Party for that portion of the Loss that would have been
          limited had the first Party included in its tariffs and contracts the
          limitations of liability that such other Party included in its own
          tariffs at the time of such Loss.

7.3.3     Neither BellSouth nor ICS shall be liable for damages to the other's
          terminal location, POI or other company's customers' premises
          resulting from the furnishing of a service, including, but not limited
          to, the installation and removal of equipment or associated wiring,
          except to the extent caused by a company's negligence or willful
          misconduct or by a company's failure to properly ground a local loop
          after disconnection.

7.3.4     Under no circumstance shall a Party be responsible or liable for
          indirect, incidental, or consequential damages, including, but not
          limited to, economic loss or lost business or profits, damages arising
          from the use or performance of equipment or software, or the loss of
          use of software or equipment, or accessories attached thereto, delay,
          error, or loss of data. In connection with this limitation of
          liability, each Party recognizes that the other Party may, from time
          to time, provide advice, make recommendations, or supply other
          analyses related to the Services, or facilities described in this
          Agreement, and, while each Party shall use diligent efforts in this
          regard, the Parties acknowledge and agree that this
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                                           General Terms and Conditions - Part A
                                                                          Page 6

          limitation of liability shall apply to provision of such advice,
          recommendations, and analyses.

7.4       Indemnification for Certain Claims. BellSouth and ICS providing
          services, their affiliates and their parent company, shall be
          indemnified, defended and held harmless by each other against any
          claim, loss or damage arising from the receiving company's use of the
          services provided under this Agreement pertaining to (1) claims for
          libel, slander, invasion of privacy or copyright infringement arising
          from the content of the receiving company's own communications, or (2)
          any claim, loss or damage claimed by the other company's customer
          arising from one company's use or reliance on the other company's
          services, actions, duties, or obligations arising out of this
          Agreement.

7.5       No liability for Certain Inaccurate Data. Neither BellSouth nor ICS
          assumes any liability for the accuracy of data provided by one Party
          to the other and each Party agrees to indemnify and hold harmless the
          other for any claim, action, cause of action, damage, or injury that
          might result from the supply of inaccurate data in conjunction with
          the provision of any service provided pursuant to this Agreement.

7.6       Disclaimer. EXCEPT AS SPECIFICALLY PROVIDED TO THE CONTRARY IN THIS
          AGREEMENT, NEITHER PARTY MAKES ANY REPRESENTATIONS OR WARRANTIES TO
          THE OTHER PARTY CONCERNING THE SPECIFIC QUALITY OF ANY SERVICES, OR
          FACILITIES PROVIDED UNDER THIS AGREEMENT. THE PARTIES DISCLAIM,
          WITHOUT LIMITATION, ANY WARRANTY OR GUARANTEE OF MERCHANTABILITY OR
          FITNESS FOR A PARTICULAR PURPOSE, ARISING FROM COURSE OF PERFORMANCE,
          COURSE OF DEALING, OR FROM USAGES OF TRADE.

8.        Intellectual Property Rights and Indemnification

8.1       No License. No patent, copyright, trademark or other proprietary right
          is licensed, granted or otherwise transferred by this Agreement. ICS
          is strictly prohibited from any use, including but not limited to in
          sales, in marketing or advertising of telecommunications services, of
          any BellSouth name, service mark or trademark.

8.2       Ownership of Intellectual Property. Any intellectual property which
          originates from or is developed by a Party shall remain in the
          exclusive ownership of that Party. Except for a limited license to use
          patents or copyrights to the extent necessary for the Parties to use
          any facilities or equipment (including software) or to receive any
          service solely as provided under this Agreement, no license in patent,
          copyright, trademark
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                                           General Terms and Conditions - Part A
                                                                          Page 7

          or trade secret, or other proprietary or intellectual property right
          now or hereafter owned, controlled or licensable by a Party, is
          granted to the other Party or shall be implied or arise by estoppel.
          It is the responsibility of each Party to ensure at no additional cost
          to the other Party that it has obtained any necessary licenses in
          relation to intellectual property of third Parties used in its network
          that may be required to enable the other Party to use any facilities
          or equipment (including software), to receive any service, or to
          perform its respective obligations under this Agreement.

8.3       Indemnification. The Party providing a service pursuant to this
          Agreement will defend the Party receiving such service or data
          provided as a result of such service against claims of infringement
          arising solely from the use by the receiving Party of such service and
          will indemnify the receiving Party for any damages awarded based
          solely on such claims in accordance with Section 7 of this Agreement.

8.4       Claim of Infringement. In the event that use of any facilities or
          equipment (including software), becomes, or in reasonable judgment of
          the Party who owns the affected network is likely to become, the
          subject of a claim, action, suit, or proceeding based on intellectual
          property infringement, then said Party shall promptly and at its sole
          expense, but subject to the limitations of liability set forth below:

8.4.1     modify or replace the applicable facilities or equipment (including
          software) while maintaining form and function, or

8.4.2     obtain a license sufficient to allow such use to continue.

8.4.3     In the event 8.4.1 or 8.4.2 are commercially unreasonable, then said
          Party may, terminate, upon reasonable notice, this contract with
          respect to use of, or services provided through use of, the affected
          facilities or equipment (including software), but solely to the extent
          required to avoid the infringement claim.

8.5       Exception to Obligations. Neither Party's obligations under this
          Section shall apply to the extent the infringement is caused by: (i)
          modification of the facilities or equipment (including software) by
          the indemnitee; (ii) use by the indemnitee of the facilities or
          equipment (including software) in combination with equipment or
          facilities (including software) not provided or authorized by the
          indemnitor provided the facilities or equipment (including software)
          would not be infringing if used alone; (iii) conformance to
          specifications of the indemnitee which would necessarily result in
          infringement; or (iv) continued use by the indemnitee of the affected
          facilities or equipment (including software) after being placed on
          notice to discontinue use as set forth herein.

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                                           General Terms and Conditions - Part A
                                                                          Page 8

8.6       Exclusive Remedy. The foregoing shall constitute the Parties' sole and
          exclusive remedies and obligations with respect to a third party claim
          of intellectual property infringement arising out of the conduct of
          business under this agreement.

9.        Treatment of Proprietary and Confidential Information

9.1       Confidential Information. It may be necessary for BellSouth and ICS to
          provide each other with certain confidential information, including
          trade secret information, including but not limited to, technical and
          business plans, technical information, proposals, specifications,
          drawings, procedures, customer account data, call detail records and
          like information (hereinafter collectively referred to as
          "Information"). All Information shall be in writing or other tangible
          form and clearly marked with a confidential, private or proprietary
          legend and that the Information will be returned to the owner within a
          reasonable time. The Information shall not be copied or reproduced in
          any form. BellSouth and ICS shall receive such Information and not
          disclose such Information. BellSouth and ICS shall protect the
          Information received from distribution, disclosure or dissemination to
          anyone except employees of BellSouth and ICS with a need to know such
          Information and which employees agree to be bound by the terms of this
          Section. BellSouth and ICS will use the same standard of care to
          protect Information received as they would use to protect their own
          confidential and proprietary Information.

9.2       Exception to Obligation. Notwithstanding the foregoing, there will be
          no obligation on BellSouth or ICS to protect any portion of the
          Information that is: (1) made publicly available by the owner of the
          Information or lawfully disclosed by a Party other than BellSouth or
          ICS; (2) lawfully obtained from any source other than the owner of the
          Information; or (3) previously known to the receiving Party without an
          obligation to keep it confidential.

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                                           General Terms and Conditions - Part A
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10.       Assignments

          Any assignment by either Party to any non-affiliated entity of any
          right, obligation or duty, or of any other interest hereunder, in
          whole or in part, without the prior written consent of the other Party
          shall be void. A Party may assign this Agreement or any right,
          obligation, duty or other interest hereunder to an Affiliate company
          of the Party without the consent of the other Party. All obligations
          and duties of any Party under this Agreement shall be binding on all
          successors in interest and assigns of such Party. No assignment of
          delegation hereof shall relieve the assignor of its obligations under
          this Agreement in the event that the assignee fails to perform such
          obligations.

11.       Resolution of Disputes

          Except as otherwise stated in this Agreement, the Parties agree that
          if any dispute arises as to the interpretation of any provision of
          this Agreement or as to the proper implementation of this Agreement,
          either Party may petition the Commission for a resolution of the
          dispute. However, each Party reserves any rights it may have to seek
          judicial review of any ruling made by the Commission concerning this
          Agreement.

12.       Taxes

12.1      Definition. For purposes of this Section, the terms"taxes" and "fees"
          shall include but not limited to federal, state or local sales, use,
          excise, gross receipts or other taxes or tax-like fees of whatever
          nature and however designated (including tariff surcharges and any
          fees, charges or other payments, contractual or otherwise, for the use
          of public streets or rights of way, whether designated as franchise
          fees or otherwise) imposed, or sought to be imposed, on or with
          respect to the services furnished hereunder or measured by the charges
          or payments therefore, excluding any taxes levied on income.

12.2      Taxes and Fees Imposed Directly On Either Seller or Purchaser.

12.2.1    Taxes and fees imposed on the providing Party, which are not permitted
          or required to be passed on by the providing Party to its customer,
          shall be borne and paid by the providing Party.

12.2.2    Taxes and fees imposed on the purchasing Party, which are not required
          to be collected and/or remitted by the providing Party, shall be borne
          and paid by the purchasing Party.

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                                           General Terms and Conditions - Part A
                                                                         Page 10

12.3      Taxes and Fees Imposed on Purchaser But Collected And Remitted By
          Seller.

12.3.1    Taxes and fees imposed on the purchasing Party shall be borne by the
          purchasing Party, even if the obligation to collect and/or remit such
          taxes or fees is placed on the providing Party.

12.3.2    To the extent permitted by applicable law, any such taxes and/or fees
          shall be shown as separate items on applicable billing documents
          between the Parties. Notwithstanding the foregoing, the purchasing
          Party shall remain liable for any such taxes and fees regardless of
          whether they are actually billed by the providing Party at the time
          that the respective service is billed.

12.3.3    If the purchasing Party determines that in its opinion any such taxes
          or fees are not payable, the providing Party shall not bill such taxes
          or fees to the purchasing Party if the purchasing Party provides
          written certification, reasonably satisfactory to the providing Party,
          stating that it is exempt or otherwise not subject to the tax or fee,
          setting forth the basis therefor, and satisfying any other
          requirements under applicable law. If any authority seeks to collect
          any such tax or fee that the purchasing Party has determined and
          certified not to be payable, or any such tax or fee that was not
          billed by the providing Party, the purchasing Party may contest the
          same in good faith, at its own expense. In any such contest, the
          purchasing Party shall promptly furnish the providing Party with
          copies of all filings in any proceeding, protest, or legal challenge,
          all rulings issued in connection therewith, and all correspondence
          between the purchasing Party and the taxing authority.

12.3.4    In the event that all or any portion of an amount sought to be
          collected must be paid in order to contest the imposition of any such
          tax or fee, or to avoid the existence of a lien on the assets of the
          providing Party during the pendency of such contest, the purchasing
          Party shall be responsible for such payment and shall be entitled to
          the benefit of any refund or recovery.

12-3.5    If it is ultimately determined that any additional amount of such a
          tax or fee is due to the imposing authority, the purchasing Party
          shall pay such additional amount, including any interest and penalties
          thereon.

12.3.6    Notwithstanding any provision to the contrary, the purchasing Party
          shall protect, indemnify and hold harmless (and defend at the
          purchasing Party's expense) the providing Party from and against any
          such tax or fee, interest or penalties thereon, or other charges or
          payable expenses (including reasonable attorney fees) with respect
          thereto, which are

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                                           General Terms and Conditions - Part A
                                                                         Page 11

          incurred by the providing Party in connection with any claim for or
          contest of any such tax or fee.

12.3.7    Each Party shall notify the other Party in writing of any assessment,
          proposed assessment or other claim for any additional amount of such a
          tax or fee by a taxing authority; such notice to be provided, if
          possible, at least ten (10) days prior to the date by which a
          response, protest or other appeal must be filed, but in no event later
          than thirty (30) days after receipt of such assessment, proposed
          assessment or claim.

12.4      Taxes and Fees Imposed on Seller But Passed On To Purchaser.

12.4.1    Taxes and fees imposed on the providing Party, which are permitted or
          required to be passed on by the providing Party to its customer, shall
          be borne by the purchasing Party.

12.4.2    To the extent permitted by applicable law, any such taxes and/or fees
          shall be shown as separate items on applicable billing documents
          between the Parties. Notwithstanding the foregoing, the purchasing
          Party shall remain liable for any such taxes and fees regardless of
          whether they are actually billed by the providing Party at the time
          that the respective service is billed.

12.4.3    If the purchasing Party disagrees with the providing Party's
          determination as to the application or basis for any such tax or fee,
          the Parties shall consult with respect to the imposition and billing
          of such tax or fee. Notwithstanding the foregoing, the providing Party
          shall retain ultimate responsibility for determining whether and to
          what extent any such taxes or fees are applicable, and the purchasing
          Party shall abide by such determination and pay such taxes or fees to
          the providing Party. The providing Party shall further retain ultimate
          responsibility for determining whether and how to contest the
          imposition of such taxes and fees; provided, however, that any such
          contest undertaken at the request of the purchasing Party shall be at
          the purchasing Party's expense.

12.4.4    In the event that all or any portion of an amount sought to be
          collected must be paid in order to contest the imposition of any such
          tax or fee, or to avoid the existence of a lien on the assets of the
          providing Party during the pendency of such contest, the purchasing
          Party shall be responsible for such payment and shall be entitled to
          the benefit of any refund or recovery.

12.4.5    If it is ultimately determined that any additional amount of such a
          tax or fee is due to the imposing authority, the purchasing Party
          shall pay such additional amount, including any interest and penalties
          thereon.
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                                           General Terms and Conditions - Part A
                                                                         Page 12

12.4.6    Notwithstanding any provision to the contrary, the purchasing Party
          shall protect indemnify and hold harmless (and defend at the
          purchasing Party's expense) the providing Party from and against any
          such tax or fee, interest or penalties thereon, or other reasonable
          charges or payable expenses (including reasonable attorney fees) with
          respect thereto, which are incurred by the providing Party in
          connection with any claim for or contest of any such tax or fee.

12.4.7    Each Party shall notify the other Party in writing of any assessment,
          proposed assessment or other claim for any additional amount of such a
          tax or fee by a taxing authority; such notice to be provided, if
          possible, at least ten (10) days prior to the date by which a
          response, protest or other appeal must be filed, but in no event later
          than thirty (30) days after receipt of such assessment, proposed
          assessment or claim.

12.5      Mutual Cooperation. In any contest of a tax or fee by one Party, the
          other Party shall cooperate fully by providing records, testimony and
          such additional information or assistance as may reasonably be
          necessary to pursue the contest. Further, the other Party shall be
          reimbursed for any reasonable and necessary out-of-pocket copying and
          travel expenses incurred in assisting in such contest.

13.       Force Majeure

          In the event performance of this Agreement, or any obligation
          hereunder, is either directly or indirectly prevented, restricted, or
          interfered with by reason of fire, flood, earthquake or like acts of
          God, wars, revolution, civil commotion, explosion, acts of public
          enemy, embargo, acts of the government in its sovereign capacity,
          labor difficulties, including without limitation, strikes, slowdowns,
          picketing, or boycotts, unavailability of equipment from vendor,
          changes requested by Customer, or any other circumstances beyond the
          reasonable control and without the 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 to
          the extent 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 until the delay, restriction or
          interference has ceased); provided however, that the Party so affected
          shall use diligent efforts to avoid or remove such causes of non-
          performance and both Parties shall proceed whenever such causes are
          removed or cease.

14.       Year 2000 Compliance

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                                           General Terms and Conditions - Part A
                                                                         Page 13

          Each party warrants that it has implemented a program the goal of
          which is to ensure that all software, hardware and related materials
          (collectively called "Systems") delivered, connected with BellSouth or
          supplied in the furtherance of the terms and conditions specified in
          this Agreement: (i) will record, store, process and display calendar
          dates falling on or after January 1, 2000, in the same manner, and
          with the same functionality as such software records, stores,
          processes and calendar dates failing on or before December 31, 1999;
          and (ii) shall include without limitation date data century
          recognition, calculations that accommodate same century and
          multicentury formulas and date values, and date data interface values
          that reflect the century.

15.       Modification of Agreement

15.1      BellSouth shall make available to ICS any interconnection, service, or
          network element provided under any other agreement filed and approved
          pursuant to 47 USC (S) 252; provided however the parties shall adopt
          such other agreement in its entirety. The adopted agreement shall
          apply to the same states as such other agreement and for the identical
          term.

15.2      No modification, amendment, supplement to, or waiver of the Agreement
          or any of its provisions shall be effective and binding upon the
          Parties unless it is made in writing and duly signed by the Parties.

15.3      Execution of this Agreement by either Party does not confirm or infer
          that the executing Party agrees with any decision(s) issued pursuant
          to the Telecommunications Act of 1996 and the consequences of those
          decisions on specific language in this Agreement. Neither Party waives
          its rights to appeal or otherwise challenge any such decision(s) and
          each Party reserves all of its rights to pursue any and all legal
          and/or equitable remedies, including appeals of any such decision(s).

15.4      In the event that any final and nonappealable legislative, regulatory,
          judicial or other legal action materially affects any material terms
          of this Agreement, or the ability of ICS or BellSouth to perform any
          material terms of this Agreement, ICS or BellSouth may, on thirty (30)
          days' written notice require that such terms be renegotiated, and the
          Parties shall renegotiate in good faith such mutually acceptable new
          terms as may be required. In the event that such new terms are not
          renegotiated within ninety (90) days after such notice, the Dispute
          shall be referred to the Dispute Resolution procedure set forth in
          Section 11.

15.5      If any provision of this Agreement, or the application of such
          provision to either Party or circumstance, shall be held invalid, the
          remainder of the Agreement, or the application of any such provision
          to the Parties or

<PAGE>

                                           General Terms and Conditions - Part A
                                                                         Page 14

          circumstances other than those to which it is held invalid, shall not
          be effective thereby, provided that the Parties shall attempt to
          reformulate such invalid provision to give effect to such portions
          thereof as may be valid without defeating the intent of such
          provision.

16.       Waivers

          A failure or delay of either Party to enforce any of the provisions
          hereof, to exercise any option which is herein provided, or to require
          performance of any of the provisions hereof shall in no way be
          construed to be a waiver of such provisions or options, and each
          Party, notwithstanding such failure, shall have the right thereafter
          to insist upon the specific performance of any and all of the
          provisions of this Agreement.

17.       Governing Law

          This Agreement shall be governed by, and construed and enforced in
          accordance with, the laws of the State of Georgia, without regard to
          its conflict of laws principles.

18.       Arm's Length Negotiations

          This Agreement was executed after arm's length negotiations between
          the undersigned Parties and reflects the conclusion of the undersigned
          that this Agreement is in the best interests of all Parties.

19.       Notices

19.1      Every notice, consent, approval, or other communications required or
          contemplated by this Agreement shall be in writing and shall be
          delivered in person or given by postage prepaid mail, address to:

               BellSouth Telecommunications, Inc.

               CLEC Account Team
               9th Floor
               600 North 19th Street
               Birmingham, Alabama 35203

               and

<PAGE>

                                           General Terms and Conditions - Part A
                                                                         Page 15

               General Attorney - COU
               Suite 4300
               675 W. Peachtree St.
               Atlanta, GA 30375

               Integrated Communications Solutions, LLC

               Bruce Becker
               6330 Quadrangle Drive, Suite 325
               Chapel Hill, NC 27514

          or at such other address as the intended recipient previously shall
          have designated by written notice to the other Party.

19.2      Where specifically required, notices shall be by certified or
          registered mail. Unless otherwise provided in this Agreement, notice
          by mail shall be effective on the date it is officially recorded as
          delivered by return receipt or equivalent, and in the absence of such
          record of delivery, it shall be presumed to have been delivered the
          fifth day, or next business day after the fifth day, after it was
          deposited in the mails.

19.3      BellSouth shall provide ICS 45-day advance notice via Internet posting
          of price changes and of changes to the terms and conditions of
          services available for resale. To the extent that revisions occur
          between the time BellSouth notifies ICS of changes under this
          Agreement and the time the changes are scheduled to be implemented,
          BellSouth will immediately notify ICS of such revisions consistent
          with its internal notification process. ICS may not hold BellSouth
          responsible for any cost incurred as a result of such revisions,
          unless such costs are incurred as a result of BellSouth's intentional
          misconduct. ICS may not utilize any notice given under this subsection
          concerning a service to market resold offerings of that service in
          advance of BellSouth.

20.       Rule of Construction

          No rule of construction requiring interpretation against the drafting
          Party hereof shall apply in the interpretation of this Agreement.

21.       Headings of No Force or Effect

          The headings of Articles and Sections of this Agreement are for
          convenience of reference only, and shall in no way define, modify or
          restrict the meaning or interpretation of the terms or provisions of
          this Agreement.

<PAGE>

                                           General Terms and Conditions - Part A
                                                                         Page 16

22.       Multiple Counterparts

          This Agreement may be executed multiple counterparts, each of which
          shall be deemed an original, but all of which shall together
          constitute but one and the same document.

23.       Implementation of Agreement

          Within 60 days of the execution of this Agreement, the parties will
          adopt a schedule for the implementation of the Agreement. The schedule
          shall state with specificity time frames for submission of including
          but not limited to, network design, interconnection points,
          collocation arrangement requests, pre-sales testing and full
          operational time frames for the business and residential markets. An
          implementation template to be used for the implementation schedule is
          contained in Attachment 12 of this Agreement.

24.       Entire Agreement

          This Agreement and its Attachments, incorporated herein by this
          reference, sets forth the entire understanding and supersedes prior
          agreements between the Parties relating to the subject matter
          contained herein and merges all prior discussions between them, and
          neither Party shall be bound by any definition, condition, provision,
          representation, warranty, covenant or promise other than as expressly
          stated in this Agreement or as is contemporaneously or subsequently
          set forth in writing and executed by a duly authorized officer or
          representative of the Party to be bound thereby.

          This agreement includes attachments with provisions for the following
          services:

          Unbundled Network Elements (UNEs)
          Local Interconnection
          Resale
          Collocation

          The following services are included as options for purchase by ICS.
          ICS shall elect said services by written request to its Account
          Manager:

          Optional Daily Usage File (ODUF)
          Access Daily Usage File (ADUF)
          Line Information Database (LIDB) Storage
          Centralized Message Distribution Service (CMDS)

<PAGE>

                                           General Terms and Conditions - Part A
                                                                         Page 17

IN WITNESS WHEREOF, the Parties have executed this Agreement the day and year
above first written.

BellSouth Telecommunications, Inc.     Integrated Communications
                                       Solutions, LLC

/s/  Jerry Hendrix                     /s/  Bruce Becker
---------------------------------      ---------------------------------
            Signature                              Signature

          Jerry Hendrix                          Bruce Becker
---------------------------------      ---------------------------------
              Name                                   Name

            Director                              President
---------------------------------      ---------------------------------
             Title                                  Title

        December 18, 1998                      December 14, 1998
---------------------------------      ---------------------------------
              Date                                   Date

<PAGE>

                                          General Terms and Conditions -- Part B
                                                                         Page 18

                                  Definitions

Affiliate is defined as a person that (directly or indirectly) owns or controls,
is owned or controlled by, or is under common ownership or control with, another
person. For purposes of this paragraph, the term "own" means to own an equity
interest (or equivalent thereof) of more than 10 percent.

Centralized Message Distribution System is the BellCore administered national
system, based in Kansas City, Missouri, used to exchange Exchange Message
Interface (EMI) formatted data among host companies.

Commission is defined as the appropriate regulatory agency in each of
BellSouth's nine state region, Alabama, Florida, Georgia, Kentucky, Louisiana,
Mississippi, North Carolina, South Carolina, and Tennessee.

Daily Usage File is the compilation of messages or copies of messages in
standard Exchange Message Interface (EMI) format exchanged from BellSouth to an
CLEC.

Exchange Message Interface is the nationally administered standard format for
the exchange of data among the Exchange Carriers within the telecommunications
industry.

Intercompany Settlements (ICS) is the revenue associated with charges billed by
a company other than the company in whose service area such charges were
incurred. ICS on a national level includes third number and credit card calls
and is administered by BellCore's Credit Card and Third Number Settlement System
(CATS). Included is traffic that originates in one Regional Bell Operating
Company's (RBOC) territory and bills in another RBOC's territory.

Intermediary function is defined as the delivery of traffic from ICS; a CLEC
other than ICS or another telecommunications carder through the network of
BellSouth or ICS to an end user of ICS; a CLEC other than ICS or another
telecommunications carrier.

Local Interconnection is defined as 1) the delivery of local traffic to be
terminated on each Party's local network so that end users of either Party have
the ability to reach end users of the other Party without the use of any access
code or substantial delay in the processing of the call; 2) the LEC unbundled
network features, functions, and capabilities set forth in this Agreement; and
3) Service Provider Number Portability sometimes referred to as temporary
telephone number portability to be implemented pursuant to the terms of this
Agreement.

Local Traffic is defined as any telephone call that originates in one exchange
and terminates in either the same exchange, or a corresponding Extended Area
Service ("EAS"). The terms Exchange and EAS exchanges are defined and specified
in Section A3 of BellSouth's General Subscriber Service Tariff. The Parties
agree that this definition shall not include traffic that originates from or
terminates to an Enhanced

<PAGE>

                                           General Terms and Conditions - Part B
                                                                         Page 19

Service Provider (ESP) or Information Service Provider (ISP) until the
Commission, the FCC or a court of competent jurisdiction determines in a final
and nonappealable order that such traffic is Local Traffic. The Parties will
maintain billing records identifying all such Enhanced Service Provider and
Information Service Provider traffic and will adjust, if necessary, their mutual
compensation billing for such local traffic termination consistent with the
final Commission, FCC or court decision. The period of adjustment shall be from
the effective date of this Agreement to the date the order of the Commission,
the FCC or the court becomes final and nonappealable.

Message Distribution is routing determination and subsequent delivery of message
data from one company to another. Also included is the interface function with
CMDS, where appropriate.

Multiple Exchange Carrier Access Billing ("MECAB") means the document prepared
by the Billing Committee of the Ordering and Billing Forum ("OBF"), which
functions under the auspices of the Carrier Liaison Committee of the Alliance
for Telecommunications Industry Solutions ("ATIS") and by Bellcore as Special
Report SR-BDS-000983, Containing the recommended guidelines for the billing of
Exchange Service access provided by two or more LECs and/or CLECs or by one LEC
in two or more states within a single LATA.

Non-intercompany Settlement System (NICS) is the BellCore system that calculates
non-intercompany settlements amounts due from one company to another within the
same RBOC region. It includes credit card, third number and collect messages.

Percent of Interstate Usage (PIU) is defined as a factor to be applied to
terminating access services minutes of use to obtain those minutes that should
be rated as interstate access services minutes of use. The numerator includes
all interstate "non-intermediary" minutes of use, including interstate minutes
of use that are forwarded due to service provider number portability less any
interstate minutes of use for Terminating Party Pays services, such as 800
Services. The denominator includes all "non-intermediary", local, interstate,
intrastate, toll and access minutes of use adjusted for service provider number
portability less all minutes attributable to terminating Party pays services.

Percent Local Usage (PLU) is defined as a factor to be applied to intrastate
terminating minutes of use. The numerator shall include all "non-intermediary"
local minutes of use adjusted for those minutes of use that only apply local due
to Service Provider Number Portability. The denominator is the total intrastate
minutes of use including local, intrastate toll, and access, adjusted for
Service Provider Number Portability less intrastate terminating Party pays
minutes of use.

<PAGE>

                                           General Terms and Conditions - Part B
                                                                         Page 20

Revenue Accounting Office (RAO) Status Company is a local exchange
company/alternate local exchange company that has been assigned a unique
RAOcode. Message data exchanged among RAO status companies is grouped (i.e.
packed) according to From/To/Bill RAO combinations.

Service Control Points ("SCPs") are defined as databases that store information
and have the ability to manipulate data required to offer particular services.

Signal Transfer Points ("STPs") are signaling message switches that interconnect
Signaling Links to route signaling messages between switches and databases. STPs
enable the exchange of Signaling System 7 ("SS7") messages between switching
elements, database elements and STPs. STPs provide access to various BellSouth
and third party network elements such as local switching and databases.

Signaling links are dedicated transmission paths carrying signaling messages
between carrier switches and signaling networks. Signal Link Transport is a set
of two or four dedicated 56 kbps transmission paths between ICS designated
Signaling Points of Interconnection that provide a diverse transmission path and
cross connect to a BellSouth Signal Transfer Point.

Telecommunications Act of 1996 ("Act") means Public Law 104-104 of the United
States Congress effective February 8, 1996. The Act amended the Communications
Act of 1934 (47, U.S.C. Section 1 et. seq.).