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                                                                   Exhibit 10.20


                      RURAL TELEPHONE FINANCE COOPERATIVE
                 UNSECURED REVOLVING LINE OF CREDIT AGREEMENT
                                 ("Agreement")


COASTAL UTILITIES, INC. a Georgia corporation ("Borrower") located at P.O. Box
585, 100Ryan Avenue, Hinesville, GA 31310-0585, hereby agrees to borrow from
RURAL TELEPHONEFINANCE COOPERATIVE ("RTFC" or "Lender"), a South Dakota
cooperative association,pursuant to the terms of this Agreement, dated as of
March 29, 2000, for a revolvingline of credit loan in an amount not to exceed
ten million dollars ($10,000,000). In consideration of their mutual premises
hereunder and other valuable consideration, the receipt and sufficiency of which
is hereby acknowledged, Lender and Borrower agree to the following terms and
conditions:


 1.  Revolving Credit and Term. Lender agrees to make advances to the Borrower
     pursuant to the terms of this Agreement ("Advances"). The maximum principal
     amount outstanding at any point in time shall not exceed $10,000,000.
     Within such limits, the Borrower may borrow, repay and reborrow at any time
     or from time to time for a period up to five (5) years from the date hereof
     (the "Maturity Date").

2.   Requisitions. The Borrower shall give Lender such prior notice of requests
     for Advances as RTFC may reasonably require from time to time.

3.   Interest Rate and Payment. The Borrower unconditionally promises and agrees
     to pay, as and when due, interest on all amounts advanced hereunder from
     the date of each Advance and to repay all amounts advanced hereunder with
     interest on the Maturity Date. Interest shall be due and payable quarterly
     on the first day of each January, April, July, and October, commencing on
     the first such date after such initial Advance; except that if Lender gives
     notice thereof to the Borrower before the first day of any month, interest
     shall thereafter be due and payable on the 15th day of such month and each
     month thereafter. Lender shall invoice the Borrower at least five (5)days
     prior to the due date of any such interest payment. All amounts shall be
     payable at RTFC's main office at Woodland Park, 2201 Cooperative Way,
     Herndon, Virginia 201713025 or at such other location as designated by
     Lender from time to time.

     The interest rate on all Advances will be equal to RTFC's standard line of
     credit as established from time to time by Lender pursuant to its policies
     and procedures plus one hundred (100) basis points. However, in no event
     shall the interest rate exceed the Prevailing Bank Prime Rate (as defined
     herein), plus one and one-half percent per annum. Interest will be computed
     on the basis of a year of 365 days. The interest rate will be adjusted as
     determined from time to time by Lender, provided that no such adjustment
     may be effective on a date other than the first or sixteenth day of any
     month, and will remain in effect until a subsequent change in rate occurs.
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     The "Prevailing Bank Prime Rate" is that bank prime rate published in the
     "Money Rates" column of any edition of The Wall Street Journal which Lender
     determines in its discretion to be the representative bank prime rate on
     the day preceding the day on which an adjustment in the interest rate
     hereof shall become effective. If such preceding day is not a publication
     day for The Wall Street Journal then the Prevailing Bank Prime Rate shall
     be established by reference to such "Money Rates" column as of the last
     publication day next preceding the day on which such adjustment shall
     become effective; provided if The Wall Street Journal shall cease to be
     published, then the Prevailing Bank Prime Rate shall be determined by RTFC
     by reference to another publication reporting bank prime rates in a similar
     manner.

4.   RTFC Accounts. Lender shall maintain in accordance with its usual practice
     an account or accounts evidencing the indebtedness of the Borrower
     resulting from each Advance made from time to time and the amounts of
     principal and interest payable and paid from time to time hereunder. In any
     legal action or proceeding in respect of this Agreement, the entries made
     in such account or accounts (whether stored on computer memory, microfilm,
     invoices or otherwise) shall be presumptive evidence (absent manifest
     error) of the existence and amounts of the Borrower's transactions therein
     recorded.

5.   Corporate and Regulatory Approvals. Borrower represents that it has
     obtained any and all necessary corporate and regulatory approvals for
     Borrower to execute and perform pursuant to this Agreement.

6.   Reports. Borrower agrees to deliver to Lender, promptly upon their becoming
     available, a copy of (i) any annual audit report prepared subsequent to the
     submission of this Agreement; (ii) its monthly operating report within
     thirty (30) days for any month in which there are advances outstanding
     pursuant to this Agreement; and (iii) any other reports which Lender
     reasonably requests during the term of this Agreement.

7.   Covenants/Financial Ratios. Until the later of (i) all Advances and fees
     hereunder having been repaid or (ii) the Maturity Date, Borrower agrees to
     honor and be bound by the affirmative and negative covenants, and financial
     ratios (collectively, the "Covenants"), contained in Sections 6 and 7 of
     the Loan Agreement by and between Borrower and Lender dated as of even date
     herewith, as it may be amended from time to time (the "Loan Agreement"),
     and such Covenants shall be incorporated by reference as if fully stated
     herein.

8.   Fees. If any amount outstanding and due hereunder shall not be paid when
     due, Borrower agrees to pay on demand Lender's reasonable costs of
     collection or enforcement of this Agreement, or preparation therefor,
     including reasonable fees of counsel. If payment of any principal and/or
     interest due under the terms of this Agreement is not received at Lender's
     office in Herndon, Virginia, or such other location designated by Lender
     within five (5) business days after the due date thereof (such unpaid
     amount of principal and/or interest being herein called the "delinquent
     amount," and the period beginning after such due date being herein called
     the "late-payment period"), Borrower will pay to Lender, on demand, in
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     addition to all other amounts due under the terms of this Agreement, any
     late-payment charge as may then be in effect pursuant to Lender's policy on
     the delinquent amount for the late payment period.

9.   Credit Support. This Agreement may not be used as credit support for any
     other financings without Lender's prior written approval.

10.  Notices,. Acceleration of Debt and Waivers. While any amount hereunder is
     outstanding, Borrower agrees to notify Lender of any delinquency or default
     on any of its financial obligations, any material adverse change in its
     financial or business condition, and if any representation or warranty made
     in this Agreement has become untrue in any respect having a material
     adverse effect on the financial condition or business of the Borrower.

     Lender may declare at any time all outstanding amounts hereunder
     immediately due and payable in full with accrued interest, without
     presentment or demand, and may withhold advances of funds upon the
     occurrence of any of the following: (i) any delinquency or default in
     payment of any sum due the Lender under the Agreement; (ii) a court shall
     enter a decree or order for relief with respect to Borrower or any
     subsidiary or guarantor in an insolvency or bankruptcy or appoint a
     receiver, liquidator, trustee or similar official and such order remains in
     effect for a period of ninety (90) days; (iii) Borrower or any subsidiary
     shall commence a voluntary case under bankruptcy, insolvency or similar law
     or consent to the appointment of a receiver, liquidator, or trustee; (iv)
     the dissolution or liquidation of Borrower or subsidiary or guarantor or
     failure to forestall or remove any execution, garnishment or attachment of
     such consequence as to impair its ability to continue business and such
     execution, garnishment or attachment shall not be vacated within thirty
     (30) days; or (v) any other event as a result of which any holder of
     indebtedness in excess of five percent (5%) of Borrower's total assets may
     declare the same due and payable shall occur and continue for more than any
     applicable grace period.

     If any representation or warranty herein shall become untrue, or Borrower
     shall fail to comply with any term of this Agreement or if the financial
     condition of Borrower shall have changed to the extent that such change in
     the reasonable judgment of RTFC, materially increases RTFC's risk
     hereunder, then RTFC at its discretion may withhold advances of funds
     and/or declare all outstanding amounts hereunder immediately due and
     payable in full with accrued interest, without presentment or demand.

     The Borrower waives the defense of usury and all rights to set off,
     counterclaim, deduction or recoupment.

11.  Purpose, Repayments and Deposit. Borrower agrees that any and all Advances
     hereunder will be used only for proper corporate purposes and consistently
     with the requirements of outstanding security documents of Borrower
     relating to its operations. Borrower agrees that this loan shall be
     repayable out of Borrower's general funds and that loan proceeds will not
     be deposited in any other account dedicated for secured financing advances.
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12.  Additional Indebtedness. While any amount hereunder is outstanding and
     unless otherwise disclosed in writing to Lender or permitted pursuant to
     the Loan Agreement, Borrower agrees that it will not, without the prior
     written consent of Lender, (i) make distributions of cash to its
     shareholders, if applicable, or (ii) create, incur, assume, guarantee or
     otherwise become obligated for any additional indebtedness, other than as
     provided for in the Loan Agreement except that the Borrower may borrow
     against another loan previously approved by Lender.

13.  Survival of Representations, Warranties and Payment Obligations. Borrower
     agrees that the representations and warranties made in this Agreement shall
     survive the making of Advances hereunder. Any unsatisfied payment
     obligation hereunder shall survive the maturity and cancellation of this
     Agreement.

14.  Representations and Warranties. Except as set forth in writing and attached
     hereto, Borrower represents and warrants as of the date of its application
     and on the date of each and every Advance hereunder that:

          (a)    The Borrower has and will meet all obligations and be in
          compliance with all instruments under which it is bound and that all
          information submitted in support of its application is true, complete
          and correct except where the failure to so comply or the inaccuracy of
          any such information could not, in either case, be reasonably be
          expected to have a Material Adverse Effect (as defined in the Loan
          Agreement);

          (b)    There has been no material adverse change in the Borrower's
          business or financial condition from that set forth in its most recent
          audited financial statements provided to Lender;

          (c)    The Borrower has no outstanding loans from sources other than
          Lender;

          (d)    The Borrower is not in default in any material respect of any
          of its obligations and no litigation is threatened or pending which
          would have a material adverse impact on the Borrower's ability to
          perform under this Agreement; and

          (e)    The Borrower has no lines of credit with any other lenders.


15.  Consent to Patronage Capital Distributions. Borrower hereby consents that
     the amount of any distributions with respect to Borrower's patronage which
     are made in written notices of allocation (as defined in Section 1388 of
     the Internal Revenue Code of 1986, as amended ("Code") including any other
     comparable successor provision) and which are received from Lender will be
     taken into account by Borrower at their stated dollar amounts in the manner
     provided in Section 1385(a) of the Code in the taxable year in which such
     written notices of allocation are received.

16.  Severability. If any term, provision or condition, or any part thereof, of
     this Agreement shall for any reason be found or held invalid or
     unenforceable by any court or
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     governmental agency of competent jurisdiction, such invalidity or
     unenforceability shall not affect the remainder of such term, provision or
     condition nor any other term, provision or condition, and this Agreement
     shall survive and be construed as if such invalid or unenforceable term,
     provision or condition had not been contained therein.

17.  Setoff. Lender is hereby authorized at any time and from time to time
     without prior notice to the Borrower to exercise rights of setoff or
     recoupment and apply any and all amounts held, or hereafter held, by Lender
     or owed to the Borrower or for the credit or account of the Borrower
     against any and all of the obligations of the Borrower now or hereafter
     existing hereunder. Lender agrees to notify the Borrower promptly after any
     such setoff or recoupment and the application thereof, provided that the
     failure to give such notice shall not affect the validity of such setoff,
     recoupment or application. The rights of Lender under this section are in
     addition to any other rights and remedies (including other rights of setoff
     or recoupment) which Lender may have.

18.  Additional Terms and Conditions. Additional terms and conditions set forth
     herein or attached hereto as Exhibit A are an integral part of this
     Agreement.

19.  Integration. This Agreement and the matters incorporated by reference
     contain the entire agreement of the parties hereto with respect to the
     matters covered and the transactions contemplated hereby, and no other
     agreement, statement or promise made by any party hereto, or by any
     employee, officer, agent or attorney of any party hereto, which is not
     contained herein, shall be valid and binding. No amendment or waiver to
     this Agreement shall be valid and binding except if in writing and signed
     by both parties.

20.  Headings. The headings and sub-headings contained in this Agreement are
     intended to be used for convenience only and do not constitute part of this
     Agreement.

21.  RESERVED.

22.  GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND BE CONSTRUED IN
     ACCORDANCE WITH THE LAWS OF THE COMMONWEALTH OF VIRGINIA.

IN WITNESS WHEREOF, the parties hereto have executed or caused to be executed
this Agreement under seal as of the date first above written.


                              COASTAL UTILITIES, INC.


                              By:  PAUL H. SUNU
                                   -----------------------------

                              Title:   Executive Vice President
                                      --------------------------
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(SEAL)


Attest:  MATT SPRINGER
         -------------------
         Assistant Secretary


                                        RURAL TELEPHONE FINANCE COOPERATIVE


                                        By: /s/ WILLIAM KNECHT, III
                                            ----------------------------------
                                             Assistant Secretary-Treasurer
(SEAL)


Attest:  BLUEPENDER SELIGAL
         -----------------------------
         Assistant Secretary-Treasurer
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                                   EXHIBIT A


Reduce Balance to Zero. Within 360 days of the first Advance, Borrower will
reduce to zero for a period of at least five consecutive business days, (the
last day of such five day period being herein called the "Zero Balance Date")
amounts outstanding hereunder, and will reduce to zero for a period of at least
five consecutive business days (the last day of such five business day period
being called the "Subsequent Zero Balance Date") amounts outstanding hereunder
within 360 days from the Zero Balance Date or Subsequent Zero Balance Date, as
appropriate.