Amazon and Microsoft have joined forces to launch a legal crackdown on alleged phishers and spammers.

The companies have filed a joint federal lawsuit against a Canadian company, Gold Disk Canada, located in Kitchener, Ontario.

The companies claim that Gold Disk Canada has been sending millions of deceptive email messages, including ones falsely purporting to have come from Amazon.com, Hotmail.com and other legitimate domains.

Microsoft internet safety enforcement attorney Aaron Kornblum said: "This is the first time we have got together with an e-tailer to stop spam and phishing, using the Can Spam legislation.

"This is not a criminal case [and] what we hope to accomplish is to get an injunction against the defendants, monetary damages and to send a message to spammers saying that spamming has consequences."

In separate legal actions, Amazon is also pursuing three other lawsuits against a number of unidentified defendants accused of phishing schemes aimed at its customers.

Microsoft, meanwhile, is filing a lawsuit against Leonid Radvinsky and his Chicago-based businesses Activsoft and Cybertania, along with several additional unidentified defendants against whom Amazon filed suit in August 2003.

The latest lawsuit alleges that Radvinsky sent millions of deceptive emails to Hotmail customers, including messages that were falsely labelled as coming from Amazon.com.

Jamie Cowper, senior technology consultant at email security specialist Mirapoint, said in the current climate this was the most effective use of the law.

"Spam will cease to exist when it no longer becomes commercially viable, and high-profile legal action such as this is a means to putting these people out of business," he said in a statement.

"When it comes to effectiveness, hitting spammers in the pocket wins hands down against the current raft of isolated and ineffectual legislation."