CHELMSFORD, Mass. -- Sonus Networks (Nasdaq: SONSE) today announced it has received written notification from Nasdaq that the Company has met all the requirements necessary for continued listing on the Nasdaq National Market. Accordingly, the Nasdaq Listing Qualifications Panel has withdrawn its prior delisting decision dated July 28, 2004 and determined to continue the listing of the Company's securities on the Nasdaq National Market.

Sonus also announced that the Company plans to file a Form 12b-25 (Notification of Late Filing) with the Securities and Exchange Commission (SEC) reporting that it will be unable to file its Quarterly Report on Form 10-Q for the quarter ended June 30, 2004 by the August 9, 2004 due date. The delay in filing Sonus' second quarter Form 10-Q is the result of the extended time Sonus spent in completing its recent detailed financial review and restating its historical financial results. The Company completed its financial review and on July 28, 2004 reported financial results for the quarter and fiscal year ended December 31, 2003 and the quarter ended March 31, 2004.

The Company also will request an exception to Nasdaq's filing requirements under Nasdaq Marketplace Rule 4310(c)(14) extending the date by which it must file its Quarterly Report on Form 10-Q for the quarter ended June 30, 2004. The Company will request an extension to August 30, 2004 and will make every effort to complete its filing by that date. At the Company's request, to minimize disruption, the "E" will not be removed from Sonus' trading symbol during the period that the Company is in compliance with the Nasdaq listing requirements. The Company's stock will continue trading under the symbol "SONSE" pending the filing of its Form 10-Q for the second quarter. Sonus' stock will be subject to delisting if Nasdaq does not grant the extension requested or Sonus does not file its Form 10-Q by any extended date granted by Nasdaq.

"Prior to the filing of our fiscal 2003 Form 10-K/A and Form 10-Q for the first quarter of 2004 last Wednesday, we dedicated ourselves to completing the complex review and preparation of our historical financial statements to bring our filings current," said Hassan Ahmed, chairman and CEO, Sonus Networks. "We are now working diligently to prepare our 10-Q filing for the second quarter and will complete this process as soon as possible."

Sonus Networks Inc.