US authorities have taken a tough stance against unwanted mail, or spam, as it is better known. Within three months of awarding social networking site MySpace a record $230 million in damages against spammer Sanford Wallace, the American legal system has sentenced Wallace's infamous peer Robert Soloway to almost four years in prison for similar offences. (See: MySpace wins record $230 million award against ''spam king'' Sanford Wallace)

Soloway, also known as the ''Spam King,'' has been sentenced to 47 months in prison after pleading guilty to accusations of fraud, spamming and tax evasion. The quantum of fines to be paid by him will be decided later.

This wasn't the first time Soloway had to face prosecutors for illicit activities on the Internet. Microsoft was the first company to take legal action against him. Soloway was sued for spamming activities in 2003. Two years later, Microsoft won the lawsuit.

On a side note, Microsoft attorney Aaron Kornblum attended the hearing and said he was pleased with the results. "Soloway repeatedly broke the law. He defied a federal judge and he made a lot of money. This sends a strong message."

In 2007, after being charged with over 40 counts of mail fraud, the ''Spam King'' only pleaded guilty on three counts, while the rest were dropped. (See: Seattle spammer Robert Alan Soloway arrested)

Although he's been lucky enough for so many years, this time the situation is different. US District Court Judge Marsha Pechman ruled that Soloway must pay for his conduct, also pointing out the necessity of creating a set of guidelines regarding these spamming acts.

The judge said it was difficult to come up with a sentence for Soloway because there have been so few other spam cases in the courts and because the legal system doesn't yet have appropriate sentencing guidelines.

"This statute really needs a set of guidelines written and tailored to the CAN-SPAM act, tailored to the evolving computer science that allows people to engage in this activity," she said. "The current guidelines are not really very helpful," especially when CAN-SPAM violations are combined with other crimes, she said.

The case has been closely watched because only a few such spam cases have ever been tried. A man named Jeremy Jaynes was sentenced in Virginia earlier this year to nine years in prison for his spam crimes, and Adam Vitale got slightly more than two years for a recent conviction in New York.

The prosecution argued that Soloway should get more prison time than any of the previous spammers, asking for a sentence of seven to nine years. "None of those cases, not one, comes close to this case in terms of the duration of the maliciousness, the harassment techniques, the high level of spamming activity that we have in this case," said assistant US attorney Kathryn Warma.

However, compared with some other notorious spammers, Soloway deserved some leniency, his attorneys said. Soloway didn't damage anyone's computer, he didn't send out malicious code, and he never directed people to pornography, as some spammers have done, his lawyer Richard Troberman said.

Jaynes, for example, had millions of AOL e-mail addresses that were stolen from the internet service provider, and he was earning as much as $700,000 a month from his activities, Troberman said. By comparison, the government figured conservatively that Soloway earned more than $700,000 in three years.