jtstalker.jpg And when we say crazy, we mean super scary 5150-style crazy!

Justin Timberlake was granted a restraining order today against Karen McNeil, a woman who has repeatedly paid visits to his Los Angeles home. And that's just the beginning! McNeil showed up at Justin's pad yesterday and wouldn't leave, so his staff called the police and she was arrested and taken to the hospital for a 5150 evaluation. Doctors determined that McNeil did not qualify for a 5150 psychiatric hold and she was released from custody today, but it looks like JT's not taking any chances!

According to legal documents McNeil took a cab to Timberlake's pad yesterday, got through the gate, gained entry to his property and then claimed to be BFFs with the star! In the court docs, Timberlake says McNeil, who is described as a heavyset woman in her 50s, is an "obsessed mentally unstable celebrity stalker, who [Timberlake] does not personally know."

And this isn't the first time McNeil has crossed the line with a famous face - the Los Angeles DA's Office tells E! News that in 1997 she pleaded no contest to two counts of disobeying a court order in which she violated an order of protection granted to Axl Rose.