Exhibit 10.21  FIRST AMENDMENT TO THE
SEVERANCE PROTECTION AGREEMENT  THIS FIRST AMENDMENT TO THE SEVERANCE PROTECTION AGREEMENT (this Amendment)
is made as of October 1, 2008, by and between NMS Communications Corporation,
a Delaware corporation (the Company), and Todd Donahue (the Executive),
Capitalized terms used herein an not otherwise defined shallhave the meaning ascribed to
them in the Severance Protection Agreement
dated as of October 1, 2007 by
and between the Company and the Executive (the Severance Agreement),  WHEREAS, the Company and the Executive have entered into Severance
Agreement;  WHEREAS, the Company is contemplating a sale of its Communications
Platform business (the Business) and has entered into an Asset Purchase
Agreement dated September 12, 2008 with Dialogic Corporation (the Asset
Purchase Agreement) pursuant to which the Company will sell substantiallyall of the assets of the Business;  WHEREAS, the Company and the Executive have agreed that the sale of the
Business will not constitute a Change of Control under the Severance
Agreement; and  WHEREAS, the Company and the Executive desire to amend the Severance
Agreementto reflect the
foregoing.  NOW,
THEREFORE, for good and valuable consideration, the receipt and sufficiency of
which is hereby acknowledged,the Company and the
Executive hereby agree:  1.That the Severance Agreement is amended by
adding the following sentence to the end of the last paragraph in Section 15.6
of the Severance Agreement:  Notwithstanding
anything to the contrary set forth herein, the sale of the Companys NMS
Communications business (orany
successor thereto, the Business)
(such sale to be referred to herein as CP Transaction) shall not constitute a
Change of Control including, without limitation, the proposed sale of the Business contemplated by that certain Asset Purchase Agreement dated as of September 12, 2008 between the Company and Dialogic Corporation (as originally executed
and as the same may be amended, supplemented or modified from time to time in accordance with its
terms), provided that any CP Transaction does not also include (i) the sale of substantially
all the assets of the Companys
LiveWire Mobile business or (ii) the sale of substantially all of the stock of the Company.  2.Except as amended by this Amendment, the
Severance Agreement remains in
full force and effect without modification or waiver.


3.This Amendment shall be governed by and
construed under the laws of the Commonwealth of Massachusetts without giving
effect to its conflict of laws provisions. Any action brought by any party to
this Amendment shall be brought and maintained in a court of competent
jurisdiction in Middlesex or Suffolk
Counties in the Commonwealth of Massachusetts.  4.This Amendment may be executed in one or more
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which together
shall be deemed to constitute one and the same agreement.  [Remainder of Page Intentionally Blank]  2


IN WITNESS WHEREOF, this Amendment has been executed as a sealed instrument
by the Company and the Executive as of the date first set forth above.  NMS COMMUNICATIONS CORPORATIONBy:
  /s/ Joel HughesName: Joel HughesTitle: President, LiveWire MobileEXECUTIVE/s/ Todd DonahueTodd Donahue  3