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                                     PROXY
                          CAPSULE COMMUNICATIONS, INC.
                 SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS

    The undersigned hereby appoints David B. Hurwitz and Randolph R. Fry (with
full power to act without the other and with power to appoint his substitute) as
the undersigned's proxies to vote all of the undersigned's shares of common
stock of Capsule Communications, Inc., a Delaware corporation (the "Company"),
which the undersigned would be entitled to vote at the Special Meeting of
Stockholders of the Company (the "Special Meeting") to be held at 11:00 a.m. on
Friday, February 8, 2002, at 11:00 a.m. local time at 3331 Street Road, Suite
275, Bensalem, Pennsylvania, and at any and all adjournments thereof as follows:

  I. Proposal to approve the Agreement and Plan of Reorganization, dated as of
   July 17, 2001, by and among Covista Communications, Inc. ("Covista"), CCI
   Acquisitions Corp., a wholly owned subsidiary of Covista, and the Company.
            / /  FOR            / /  AGAINST            / /  ABSTAIN

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II. In their discretion, upon such other business as may properly come before
the Special Meeting or any adjournments or postponements thereof.

    THE SHARES OF COMMON STOCK REPRESENTED BY THIS PROXY WILL BE VOTED IN
ACCORDANCE WITH THE FOREGOING INSTRUCTIONS. IN THE ABSENCE OF ANY INSTRUCTIONS,
SUCH SHARES WILL BE VOTED FOR THE PROPOSAL IN ITEM I.
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    The undersigned hereby acknowledges receipt of the Notice of Special Meeting
to be held on February 8, 2002 and the Proxy Statement of the Company, each
dated January 9, 2002, each of which has been enclosed herewith.

    The undersigned hereby revokes any proxy to vote shares of common stock of
the Company heretofore given by the undersigned.

                                              Dated ____________________________

                                              __________________________________
                                                          Signature

                                              __________________________________
                                                  Signature, if held jointly

                                              __________________________________
                                                    Title (if applicable)

    Please date, sign exactly as your name appears on this Proxy and promptly
return in the enclosed envelope. In the case of joint ownership, each joint
owner must sign. When signing as guardian, executor, administrator, attorney,
trustee, custodian, or in any other similar capacity, please give full title. If
a corporation, sign in full corporate name by president or other authorized
officer, giving title, and affix corporate seal. If a partnership, sign in
partnership name by authorized person.