A new version of Symantec's gateway anti-virus product adds features that the company claims will block spam e-mail messages.
The new antispam features are included in Version 3.1 of the AntiVirus for SMTP Gateways, an email security product targeted at large enterprises that relies on a multilayered approach to fighting the spam problem, Symantec said.
The new antispam features are a heuristic scanning engine that uses neural-network technology to spot spam email messages, support for checking against multiple real-time blacklists of known spam sources, customised spam "whitelists" for authorised sources, and subject line filtering.
The combination of blacklists with heuristics was the key to the new software, Symantec said.
While antispam software that relied on blacklists, or "signatures", often reacted too slowly to rapidly changing spam formats, those that relied purely on content analysis using heuristics could produce high numbers of false positives or false negatives, Symantec said.
Messages that were flagged by the product would be forwarded to a pre-determined administrative email account, but the product did not not offer mailbox or server level quarantines for suspected spam, the company said.
The combination of blacklists and heuristics, along with more traditional strategies such as subject line filtering, should help companies stem the tide of unsolicited email messages that arrived at their email gateways each day, Symantec said.