Norton anti-virus maker Symantec Corp. Wednesday said it will plunk down upwards of $355 million in cash to acquire three separate companies for its security product lineup.

The Cupertino, Calif.-based company said it has signed an agreement to acquire Riptech, Inc. for an estimated $145 million; Recourse Technologies for about $135 million; and SecurityFocus for approximately $75 million.

Symantec's current products include its Norton brand of client, gateway and server security solutions for virus protection, firewall and virtual private network, vulnerability management, intrusion detection, Internet content and e-mail filtering, remote management technologies and security services.

This marks the fourth acquisition announced by Symantec this month. The company recently said it will shell out $20 million for Falls Church, Va.-based Mountain Wave and its CyberWolf technology.

The purchases are expected to help Symantec keep pace with Silicon Valley-based rivals Network Associates and , which are are in the middle of negotiating a deal that would merge the two companies back together.

"The acquisitions we announced today bring next generation security technology, products and services that will help us to better serve the needs of our customers and continue to deliver strong top and bottom-line growth." said Symantec Chairman and CEO John Thompson. "We believe it is important to sometimes look beyond our walls to increase our product strength."

Thompson also said the online security sector on the whole is still in its infancy stage and that the market needs to keep constant vigilance over major online attacks.

Symantec said Recourse's technology will allow it to compete in the gigabit-performance network intrusion detection space with the addition of Recourse's IntruderAlert platform. The Redwood City, Calif.-based company also makes ManHunt and ManTrap "honeypot" solutions.

Alexandria, Va.-based Riptech's Caltarian platform is expected to give Symantec real-time managed security services. The combination of Symantec and Riptech will create a global network of world-class Security Operations Centers in Virginia, Texas, the United Kingdom, Germany and Japan.

SecurityFocus, based in San Mateo, Calif., will give Symantec a vulnerability database and early warning threat management products to pad Symantec's anti-virus research and response capabilities. Symantec said it will continue to manage SecurityFocus' popular Bugtraq mailing list and the online security community under the SecurityFocus brand. The company said it will also integrate the DeepSight line of global threat management solutions, including Security Focus' DeepSight Threat Management System.

If the positive news of acquisitions wasn't enough, Symantec also reported its first quarter fiscal earnings, which the company said it took in a 39 percent increase in revenue compared with last year. The company reported its pro forma earnings per share hit $0.41, compared to pro forma earnings per share of $0.22 for the year-ago quarter.

The company said net income including one-time charges and the amortization of acquisition-related intangible assets for the first quarter was $56.6 million, compared to a net loss of $21.2 million from the same quarter last year.

Symantec reported earnings per share of $0.36, compared to a net loss per share of $0.14 for the year-ago quarter. Part of that includes one-time charges for the quarter for expenses related to a restructuring announced earlier this year.