It has been responsible for helping its members fall in love, getting them sacked, and destroying their relationships thanks to indiscreet behaviour broadcast to the world.

Now Facebook is being used to repossess an Australian couple's home.

In what may be a legal first, an Australian lawyer has used the social networking site to serve legal documents on a couple who defaulted on their mortgage.

In a ruling that appears to have no precedent in internet history, a Supreme Court judge in the Australia Capital Territory (ACT) has ruled that court notices served on the site were binding.

Mark MacCormack, who works for the Canberra law firm Meyer Vandenberg had to get imaginative when conventional methods to find the couple failed.

Carmel Corbo and Gordon Poyser had defaulted on a $150,000 loan they had borrowed from MKM Capital, a mortgage provider.

The company had been granted a default judgment for the loan amount but despite repeated attempts to serve the papers to them personally, the couple appeared to have vanished.

So the lawyer and his partner, Jason Oliver, turned to the web for inspiration.

"We made at least 10 visits to their home and places of work," Mr McCormack told The Times.

"Once we'd established that they no longer lived there we looked at the other information we had available to us. Email was one way to serve the papers but some people don't check their email regularly."

A keen Facebook user, Mr MrCormack put the details provided by the couple on their mortgage application, including their e-mail addresses and dates of birth into the Facebook site.

Less than a minute later, he had tracked them down.

"It took about 30 seconds to find them," he said.

"We put the e-mail address of one of the defendants into Facebook and their profile came up with a range of information that was identical to that on their mortgae application.

What's more, they had the other defendant in their list of 'Facebook friends'."

That was enough to convince Master David Harper, the Supreme Court judge who heard the application, that Facebook was a sufficient method of communicating with defendants.

"We checked, but we can't find any other lawyer who has used Facebook in this way," said Mr McCormack.

However, he said, although Mr Harper was convinced that the lawyers had tried every other available means to contact the couple, it did take some explaining before he agreed that Facebook could be used to serve the papers.

"He admitted that he didn't have a Facebook account, so we had to explain to him how it worked," he said.

The couple now has seven days to respond to the papers before the loan company moves to repossess their home.

Facebook has attracted more than 140 million users worldwide since it launched in 2004.

In April, a Queensland state District Court judge ruled against documents being served by Facebook because the option of contacting a person via a post office box had not yet been exhausted.

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