The war on spam is far from over, but there was a growing sense among the antispam crusaders gathered at MIT last week that advances on both the legal and technology fronts have turned the tide against the Viagra peddlers and Nigerian princesses.

Nobody was claiming that spam will ever be completely eliminated, or even that the amount of spam is decreasing. In fact, antispam newsletter writer John Graham-Cumming reported that he conducted an online survey in which spam accounted for 77 percent of e-mail messages received by the nearly 5,000 respondents.

But the crowd of more than 100 members of the spam fighting fraternity was buoyed by several of the day's presentations.

On the legal front, Jon Praed, founding partner of the Internet Law Group, drew cheers when he reported that convicted North Carolina spammer Jeremy Jaynes was sentenced in November to nine years in a Virginia jail. Jaynes -- No. 8 on Spamhaus's Register of Known Spam Operations, or Rokso, list -- was charged with sending millions of pieces of spam via a program called RoboMail to America Online Inc. customers in 2003. AOL is based in Virginia.

Jaynes is the first person ever convicted in the U.S. on felony spam charges, which were based on a tough Virginia law in which penalties increase based on the number of fraudulent messages sent. Virginia Attorney General Jerry Kilgore is not letting up, either -- last May he arrested a woman in Fort Worth, Texas, and brought her to Virginia to face spam charges. That trial hasn't started yet.

"I can guarantee that spammers today are scared to death that they're next," Praed said. He added that tough laws are only part of the equation. "The solution is a marriage of technology and law."

On the tech side, amid presentations on Bayesian noise reduction, lexicographical distancing, and classifier aggregation, there was a general sense that spam filters had gotten about as good as they're going to get, which is pretty darn good.

"In general, we're doing a good job keeping spam out of people's inbox," said Andrew Klein, product manager for spam filter company MailFrontier Inc. With success rates currently in the 97 percent to 98 percent range, Klein said, "I don't know if we can get much better." He said that no product will ever eradicate all spam, but today's products can reduce spam to "an acceptable level."

Graham-Cumming, who is also chief scientist at Electric Cloud, added that Bayesian filtering, the technique used in most antispam products, effectively solves the spam problem for most people. "The reality is that these things work extremely well," he said.

Matthew Prince, CEO of Unspam, said he has opened another line of attack against spammers with Project Honeypot. Under the federal CAN-SPAM law, harvesting e-mail addresses for use by spammers is illegal, so Prince is soliciting volunteers who will agree to plant fake e-mail addresses on their networks all over the world. The idea is to track those e-mail addresses to try to catch the harvesters.

While the presenters were upbeat about the legal and technical approaches to fighting spam, they conceded that human behavior is a tougher nut to crack. Brian McWilliams, whose book "Spam Kings" profiles some of the nation's most notorious spammers, argued that blocking spam and dumping it into a separate folder won't stop some people from digging through their spam folder and buying stuff anyway.

Graham-Cumming said that 1 percent of people in his survey, and 2 percent of people over the age of 55, said they bought from known spammers. And when you're sending out millions of e-mail messages, that's enough to make spamming profitable.

This was the third annual Spam Conference, and maybe the last. The auditorium in Building 29 on the MIT campus was packed the last two years, but there were plenty of empty seats this time around.

"There's not so much of a sense of urgency this year," said antispam champion Paul Graham, credited with writing a paper in 2002 that led to the Bayesian filters. "The technology problem is pretty close to being solved," he said. And the recent legal action is having "a chilling effect" on spammers.