EXHIBIT 10.28

ASSIGNMENT AND ASSUMPTION OF LEASE

[Xpedite to ATS – Atlanta, GA]

     THIS ASSIGNMENT AND ASSUMPTION OF LEASE (this “Assignment”) is entered into
as of the 20th day of October, 2010 (the “Effective Date”), by and between
XPEDITE SYSTEMS, LLC, a Delaware limited liability company (“Assignor”), and
AMERICAN TELECONFERENCING SERVICES, LTD., a Missouri corporation (“Assignee”).

W I T N E S S E T H :

     WHEREAS, Assignor is the tenant under certain leases (the “Leases”) which
are more particularly described on Exhibit A attached hereto; and

     WHEREAS, Assignor desires to assign the Leases to Assignee, and Assignee
desires to assume the Leases from Assignor, subject to the terms and conditions
of this Assignment.

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
hereinafter set forth and other good and valuable consideration the receipt and
sufficiency of which are hereby acknowledged, Assignor and Assignee agree as
follows:

     1. Assignment. Assignor hereby transfers and assigns to Assignee, effective
as of the Effective Date, all of Assignor’s right, title and interest in and to,
and obligations under, the Leases, including any security deposits. Assignor
does hereby agree to indemnify and hold harmless Assignee from and against any
and all claims or damages (including reasonable attorneys’ fees) incurred or
suffered by Assignee resulting from any failure on the part of Assignor to
discharge or perform any obligations or liabilities arising under the Leases
prior to the Effective Date.

     2. Assumption. Assignee does hereby assume and accept the assignment of the
Leases, and agrees to perform the obligations of Assignor under the Leases in
accordance with the terms thereof, except any obligations or liabilities arising
prior to the Effective Date. Assignee does hereby agree to indemnify and hold
harmless Assignor from and against any and all claims or damages (including
expenses and reasonable attorneys’ fees) incurred or suffered by Assignor
resulting from any failure on the part of the Assignee to discharge or perform
any obligations or liabilities arising under the Leases on or after the
Effective Date.

     3. Miscellaneous. This Assignment shall be binding upon each party and
their respective successors and assigns. This Assignment may be executed in one
or more counterparts, each of which shall be deemed an original and all of
which, taken together, shall be construed as a single instrument. Each party
shall be authorized to accept, and may rely upon, an electronic transmission of
this Assignment (e.g., by facsimile or e-mail) executed by the other party and
such document shall be binding upon the executing party. As to each Lease, this
Assignment shall be governed by and construed under the laws of the state in
which the premises which are the subject of such Lease are located.

[Signatures on following page]

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     IN WITNESS WHEREOF, Assignor and Assignee have executed this Assignment and
Assumption of Lease as of the Effective Date.

  ASSIGNOR:         XPEDITE SYSTEMS, LLC           By: /s/ Scott Askins Leonard
   

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  Print name: Scott Askins Leonard    

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  Title: SVP-Legal    

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  ASSIGNEE:         AMERICAN TELECONFERENCING
SERVICES, LTD.           By: /s/ Scott Askins Leonard    

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  Print name: Scott Askins Leonard    

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  Title: SVP-Legal    

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Exhibit A to Assignment and Assumption of Lease

     Lease Agreement between 3280 Peachtree I LLC, as Landlord, and Xpedite
Systems, LLC, dated October 28, 2005, as amended by First Amendment to Lease
Agreement dated July 14, 2006, as amended by Second Amendment to Lease Agreement
dated March 15, 2007, and as amended by Third Amendment to Lease Agreement dated
June 3, 2008, for Suite 1000, 3280 Peachtree Road, Atlanta, Georgia 30327,
containing approximately 23,684 rentable square feet on the 10th floor of the
building.

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