NORTH BILLERICA, Mass. -- Avici Systems Inc. (Nasdaq:AVCI - news), today announced that a shareholder class action lawsuit was filed against the Company in the United States District Court Southern District of New York purportedly on behalf of purchasers of the Company's common stock during the period July 28, 2000 to April 20, 2001. The complaint also names as defendants Morgan Stanley & Co. Incorporated and certain officers of the Company. The complaint alleges violations of federal securities laws regarding statements concerning the underwriting of its shares to the public made in the Company's initial public offering registration statement.

Avici Systems and its officers deny any liability in the litigation and intend to vigorously defend the allegations against them.

Avici Systems Inc.