In an attempt to block unwanted e-mail, an automatic function on the company's new Outlook 98 messaging software filters messages based on a pre-set list of words and punctuation. The feature blocks messages that have an exclamation point and question mark in the subject line, as well as such words or phrases as "for free!" and "removal instructions" in the body. The filter is intended to block annoying mass e-mailings that often contain promises of free trips and get-rich-quick schemes, but it also may filter out other messages. For example, a message with "Hey! Guess What?" in the subject and "I'm getting tickets to tonight's baseball game for free!" could be blocked if a person chooses Outlook's automatic filter. The company came up with the phrases by studying more than 2 million pieces of spam, according to Microsoft Outlook product manager, George Meng. "It's not an exact science yet," said Meng, adding the company is working with third parties to develop more advanced filters. A free version of Outlook 98 is available on the company's Web site, with a final version set to ship in the first half of this year. People who don't want to use the automatic filter can build a customised blocking program, choosing specific words and domain names to block. But the automatic filter cannot be adjusted. The program also has a feature that turns spam a different colour on a user's screen instead of just deleting it. But some analysts say users of the automatic filter aren't warned of the text-based feature. "A lot of people put question marks and exclamation points in their messages," said Peter Ghosh, senior consultant with Philadelphia systems integrator JVC Technologies. "The other problem is there's nothing that allows you to edit it." Stanton McCandlish, program director for US free-speech group Electronic Frontier Foundation, said Microsoft's list may be going too far. "It sounds like they've not really thought through what the key words are," said McCandlish, who filters out messages with multiple, consecutive exclamation points. Microsoft isn't the only company grappling with new ways to intelligently filter unwanted e-mail. Spammers are increasingly finding ways to get around the popular domain name-based filters, forcing messaging software to develop more creative ways to deal with the problem, such as Microsoft's text-based approach. Ron Rassner, a consultant with Creative Networks in the US, expects more companies to come out with text-based filtering systems in the coming months, but he said people should always customise their blocking features instead of just relying on automatic filters. "Of course the spammers will just respond by figuring a way around it," Rassner said.