Microsoft Chairman and Chief Software Architect Bill Gates will use his keynote address on Sunday at the annual Comdex 2003 trade show in Las Vegas to announce plans to make the company's Exchange e-mail server better at stopping unsolicited commercial ("spam") e-mail, according to information obtained by IDG News Service.

Among other things, Gates will announce that Microsoft is adding heuristics-based anti-spam capabilities to future releases of Exchange Server 2003, which will enable Exchange Server to stop spam e-mail messages before they reach users' e-mail inboxes.

Microsoft declined to comment in detail about Gates' keynote, but a spokesman did confirm that the company is making an announcement that pertains to spam and Exchange.

Heuristics anti-spam technology analyzes patterns of content in large numbers of messages, using that information to screen out new threats. The technology is considered more flexible and effective than so-called "signature-based" anti-spam products, which identify spam messages by matching them to copies of the same messages which have already been received.

The new anti-spam feature, which Microsoft is calling the Exchange Intelligent Message Filter (IMF), uses heuristics technology developed internally at Microsoft, according to the information.

Information from Microsoft's Hotmail free Web-based e-mail service will be used to keep the Microsoft heuristics database up-to-date on the most recent spam trends.

The new anti-spam features will be offered to customers who sign on to Microsoft's Software Assurance program, which streamlines licensing different Microsoft products and gives customers automatic product update rights. A beta version of the antispam features will be available within a month, but Microsoft is not saying when the features will be generally available to Exchange customers, according to sources familiar with the company's plans.

Gates' Comdex keynotes are a staple of the annual industry trade show and are often used to highlight key initiatives at the Redmond, Wash., company.

In last year's address, Gates described a world of consumer applications for his company's software, including lightweight, portable tablet personal computers, software to replace the paper note pad and home entertainment systems powered by the Windows operating system.

The IDG News Service is a Network World affiliate.