Steve-O has been hospitalized for observation, sources close to the stuntman confirmed to MTV News on Thursday (March 13).

On Sunday, the "Jackass" star was planning to execute a stunt where he would take a 25-foot fall onto concrete, a fall he hoped to break with cardboard boxes and trash cans, so long as his friends showed up to provide them. "50 Cent got shot nine times at once and survived, and he is forever a legend," Steve-O (real name: Stephen Glover) wrote to his e-mail list. "I betcha I break more than nine bones if nobody comes with something to catch me, because, mark my words, I will fall!" In separate e-mails, he wrote repeatedly, "I'm ready to f---ing die."

But it wasn't an injury from this stunt that landed him in lockdown at Cedars-Sinai Medical Center on Sunday, after being taken there by Johnny Knoxville and Dimitry Elyaschevich, according to their mutual friends. Rather, it was concern over his recent behavior that precipitated it. "He's in the hospital now," one of his friends told MTV News. "Not for injury, for observation." His friends estimate that he'll be in the hospital for 14 days.

A week before the stunt, Glover had been arrested for allegedly vandalizing his neighbor's property, and a felony drug charge for possession of cocaine during the incident was added this week, his arraignment for which was scheduled for Thursday. As Glover was not available to enter a plea, an attorney went to court on his behalf to explain the circumstances and ask for a continuance, so the arraignment was pushed back until March 26.

It was Glover's arrest a week ago that precipitated this situation, however. As a result of the vandalism charge and the subsequent media attention, Glover was evicted from his apartment and decided to do the stunt as a last hurrah, to take advantage of the clearing from the loft. In planning that stunt, the references to dying and suicide in his e-mails concerned his friends and family the most, especially coming on the heels of his girlfriend rejecting a marriage proposal, which he also wrote about. "These last e-mails definitely had something to do with it," another friend said, "but he's been headed towards this for a few months."

"My family is convinced that I've got bipolar disorder," Glover wrote in November. "I don't know if I agree, but I've come to terms with the fact that I'm somewhat f---ed in the head. ... I agreed to go to a psychiatrist for a professional evaluation, to try and figure out what specific category of nutjob I fall into. I've decided that I want to make a rad project out of finding what the f--- is wrong with me. I sure hope this psychiatrist is down with me having my evaluation filmed."

No word on whether Cedars-Sinai is allowing Steve-O to document his lockdown, as a rep for the hospital could not confirm his admittance, citing patient confidentiality, but regardless, his friends predict he'll be fine in a few weeks. "Once he dries out in there," one friend said, "he'll be back to happy old funny Steve-O."