A brother and sister were convicted yesterday on three criminal charges for sending spam, giving them the dubious honour of being the world's first-ever e-mail convicts.

The two were found guilty of sending thousands of junk e-mails through servers located in Virginia, said the state's attorney general Jerry Kilgore.

Jeremy Jaynes was sentenced to nine years in jail, and his sister, Jessica DeGroot, was fined $7,500. A third defendant, Richard Rutkowski, was found not guilty, the attorney general said. The case was prosecuted by members of the attorney general's Computer Crimes Unit under Virginia's new anti-spam law, which took effect last year.

"This is a major victory for Virginians and all Americans," Kilgore said. "Spam is a nuisance to millions of Americans, but it is also a major problem for businesses large and small because the thousands of unwanted e-mails create havoc as they attempt to conduct commerce." Jaynes was rated the world's eighth most prolific spammer by the Register of Known Spam Operations.

DeGroot was convicted after prosecutors proved she had used her credit card to purchase domain names for the purpose of sending spam. Jaynes surrendered to the authorities last December. DeGroot turned herself in in April.

The indictment covered spam sent in 2003 between 11 July and 9 August. On three particular days, more than 10,000 complaints about spam sent by Jaynes were received by ISPs over each 24-hour period.

The indictment also said that Jaynes had falsified transmission or routing information to prevent recipients from knowing who had sent the messages and how to contact the sender. This falsified information is what made the spam a crime in Virginia, and the volume of e-mails sent during the period is what elevated the charge to criminal status, according to the statement.