Symantec's Whole Security Buy Adds New Anti-Virus Tools.(Symantec Corp.)

In a deal that may bring it more financial services customers, the Internet security giant Symantec Corp. is buying WholeSecurity Inc., whose software attacks viruses from a different slant.

Symantec, of Cupertino, Calif., is well known among consumers and corporate IT workers for its strong anti-virus products, many of them marketed under the Norton brand.

When a virus starts to spread on the Internet, Symantec defines its "signature" -- a description its customers can download so their computers can spot and stop the malicious software. But this strategy is more effective against widespread threats than against viruses written to prey on customers of a …