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.However, a recent spate of virus and worm outbreaks targeting Microsoft's products and the company's recent disclosure that security concerns were eating into its licensing revenue have pushed existing software security talk to the forefront of the company's public relations efforts.In recent weeks, Gates has publicly said that Microsoft will continue to invest some of its research and development budget in designing software that can prevent attacks, including spam.Microsoft introduced several new features in Exchange 2003, which was released in October, that were designed to help stop spam and e-mail borne viruses. Those include a feature that enables third party anti-spam vendors to assign a spam "confidence rating" to incoming e-mail messages. Exchange administrators can then use a spam confidence "threshold." Messages with a confidence rating above the threshold level automatically get quarantined or sent to a junk mail folder.Most anti-virus software vendors have also moved, in the past year, to integrate anti-spam technology with their products, responding to rapid growth in the volume of unwanted e-mail messages.In recent days, Microsoft has briefed antivirus vendors on its plans, telling them that it wants to work with them to stop spam e-mail using a multiple filter approach, that its IMF lacks features they have in their products and that all the parties involved are better off working together to fight spam, according to a source at a leading anti-virus company.A decision to move to a server-based approach to fighting spam would not be surprising, especially since Microsoft did not add to enhance anti-spam features in the recent Outlook e-mail client, which was released in October as part of Office 2003, according to John Pescatore, an analyst at Gartner."It's a lot more effective to do (anti-spam scanning) on the server end, " Pescatore said.While viruses and worms may be more destructive, spam is the number one problem identified by e-mail users, according to James Kobielus, a senior analyst Burton Group."People worry about viruses like they worry about terrorist attacks. (Viruses) are highly destructive, but they're also more manageable in terms of (an e-mail user's) day-to-day stress level than spam," he said.Microsoft technology is not implicated in the growth of spam e-mail, as it sometimes is when viruses maximize security holes in the company's products, Kobielus and Pescatore said.However, as with viruses, Microsoft feels the wrath of customers who are being overwhelmed with spam e-mail delivered through its Exchange, Outlook and Hotmail messaging products, driving the company to try to make its messaging products more secure, they said.