Howard Carmack, known as the "Buffalo Spammer," received the maximum sentence for 14 counts of identity theft and forgery, a spokesman for New York Attorney General Eliot Spitzer said.

Carmack sent out 825 million bulk e-mail messages using stolen identities and forged addresses, the court found, and was the first defendant to face charges under the state's new identity-theft statute.

He was found guilty in April.

The forgery conviction fetched the longest sentence, while the other convictions drew shorter sentences of one year to four years. All will be served concurrently, Spitzer spokesman Brad Maione said.

Carmack could be out in 3-1/2 years should he behave in prison, Maione said.

Internet provider EarthLink Inc. won a $16.5 million judgment against Carmack last year, and EarthLink officials testified in the criminal trial as well.

"We're satisfied that today's sentencing sends a strong message to spammers, and EarthLink will continue to investigate spammers and work with law enforcement," said EarthLink assistant general counsel Karen Cashion in a statement.

Unwanted bulk messages now account for roughly 83 percent of e-mail traffic, according to filtering company Postini Inc.

Many of Carmack's alleged activities are illegal under a national anti-spam law that took effect in January, seven months after he was charged.