Acme Packet Announces Closing of Public Offering and Underwriters' Exercise of Option to Purchase Additional Shares.

BURLINGTON, Mass. -- Acme Packet, Inc. (NASDAQ: APKT) today announced the completion of its initial public offering of 11.5 million common shares at a price of $9.50 per share. Of the shares sold in the offering, 8.0 million shares were offered by the Company and 3.5 million shares were offered by selling stockholders. The Company also announced today that the underwriters of its initial public offering exercised in full their option to purchase an additional 1.7 million common shares from the Company.

Goldman, Sachs & Co. is the sole book-running manager, Credit Suisse is co-lead manager, and JPMorgan and ThinkEquity Partners are co-managers for the offering. A copy of the final prospectus relating to the offering may be obtained by contacting Goldman, Sachs & Co., Attn: Prospectus Department, 85 Broad Street, New York, New York 10004, via fax at 212-902-9316 or via e-mail at [e-mail].

This press release shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About Acme Packet, Inc.

Acme Packet, Inc., the leader in session border control solutions, enables service providers to deliver trusted, first class interactive communications - voice, video and multimedia sessions - across IP network borders.