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                                                                Exhibit (10)(AO)

                             LEASE SCHEDULE NO. 001
                                       TO
                       MASTER LEASE AGREEMENT NO. AFI0192

     Reference is made to Lease Schedule No. 001 dated July 25, 2001 (the
"Schedule") to Master Lease Agreement No. AFI0192 dated July 25, 2001 (the
"Master Lease") between APPLIED FINANCIAL, INC. (the "Lessor") and COVISTA
COMMUNICATIONS, INC. (the "Lessee").

     This Schedule incorporates by reference the terms and conditions of the
Master Lease, Exhibit A (the "Property Description") and Exhibit B (the
"Casualty Loss Schedule"), and constitutes a separate "Lease" between Lessor and
Lessee. All capitalized terms used herein but not defined herein shall have the
same meanings ascribed to them in the Master Lease.

1.   Property: Alcatel Phone Switch as more fully described on the attached
     Exhibit A of two (2) pages, which by this reference becomes a part hereof.

2.   Property Location: 3270 Summit Ridge Parkway, Duluth, GA 30096

3.   Acceptance Date: As specified in the Acceptance Certificate

4.   Initial Period: Thirty-six (36) months from Commencement Date

5.   Monthly Rental: $35,803.49, plus applicable sales tax

6.   Deposit: $35,803.49 applied to the last Monthly Rental, plus applicable
     sales tax

7.   Total Cost: $1,245,338.80

8.   Lease Rate Factor: .02875

9.   Floating Lease Rate Factor: The Lease Rate Factor of .02875 shall increase
     .000069966 for every five (05) basis point increase in thirty-six (36)
     month U.S. Treasury Notes as of the Acceptance Date of the Property (the
     "Revised Lease Rate Factor"), at which time the final Monthly Rental under
     this Schedule shall be adjusted by multiplying the Total Cost, indicated in
     Section 7, by the Revised Lease Rate Factor. The thirty-six (36) month U.S.
     Treasury Note yield used as the basis for the derivation of the Revised
     Lease Rate Factor herein is 4.40%.




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10.  For purposes of this Lease Schedule No. 1 only, and provided no Event of
     Default has occurred and is continuing under the Lease, the following
     amendment shall apply: In the fourth line of Section 18(m) of the Master
     Lease "twelve (12) additional months" shall be changed to "seven (7)
     additional months". In the fifth line of Section 18(m) of the Master Lease
     immediately after the phrase "at the rate specified on the respective
     Schedule", insert the phrase "after which Lessee shall purchase all, but
     not less than all, of the Property for the price of $1.00.

11.  Representation of Lessee: Lessor and Lessee agree that this Schedule
     constitutes a "finance lease" under the Uniform Commercial Code - Article
     2A, in that (a) Lessee has selected the Property in its sole discretion,
     (b) Lessor has acquired the Property solely for purposes of leasing such
     Property under this Schedule, and (c) Lessee has received a copy of the
     contract evidencing Lessor's purchase of the Property.

LESSOR:                                           LESSEE:

APPLIED FINANCIAL, INC.                           COVISTA COMMUNICATIONS, INC.


BY: Kay Paul                                      BY: Illegible
    --------------------------------                  --------------------------
TITLE: Assistant Vice President                   TITLE: Secretary/Treasurer