Source: Mischa Barton Placed Under Involuntary Psychiatric Hold  —  Mischa Barton was placed under an involuntary psychiatric hold (also known as a 5150) by the Los Angeles Police Department and transferred to Cedars-Sinai Medical Center on Wednesday evening, a source close to the situation claimed to Access Hollywood.

Janet Jackson, Jermaine Dupri Split  —  On July 7, Michael Jackson's family ­gathered to celebrate him at his much-watched memorial service.  —  Noticeably absent?  —  Janet ­Jackson's longtime music-exec boyfriend, Jermaine Dupri.  (A pal says Dupri skipped the memorial because he “doesn't attend funerals.")

‘Prince of Persia’: Exclusive first look at star Jake Gyllenhaal!  —  For Jake Gyllenhaal, playing Prince Dastan in Jerry Bruckheimer's epic Prince of Persia: Sands of Time, due May 28, 2010, was a chance to get into some serious action.  (Paparazzi photos of Gyllenhaal on-set have appeared previously …

Twilight movie ‘Eclipse’ has its first new casting  —  Google might want to brace for a search onslaught: An unknown Australian actor named Xavier Samuel has landed the first new role in “Eclipse,” the third “Twilight” pic.  —  Summit has hired the actor to play the role of a “newborn vampire” …

Gerard Butler: Jennifer Aniston “Laughs About” Relationship Rumors  —  Gerard Butler says he and Jennifer Aniston don't take romance rumors too seriously.  —  “It depends what mood I'm in, [but] most of the time I just laugh it off,” Butler told Usmagazine.com at the NYC premiere of The Ugly Truth Thursday night.

Rowe Sues Over Bogus Custody Claims  —  Debbie Rowe is taking legal action after a recent news report claimed she was seeking a massive buyout in the custody battle over Michael Jackson's children.  Rowe, the ex-wife of Jackson and biological mother of two children, has filed a defamation suit …

Actor James Caviezel hurt in motorcycle accident  —  LEAVENWORTH, Wash. — The Washington State Patrol says James Caviezel suffered cuts and bruises when a man hurled a bicycle into the path of his Harley-Davidson motorcycle.  —  Trooper Rich Magnussen says “The Passion of the Christ” …

Leelee Sobieski Is Engaged  —  Sobieski, 26, donned her marquise diamond engagement ring to the L.A. premiere of her latest flick, the Johnny Depp drama Public Enemies, in Los Angeles June 23.  On the red carpet, Sobieski told Us she was “leaving to meet him in Paris” the next day.

Tony Romo Gambles with Pals After Splitting from Jessica  —  Looks like he's not lucky in love - or blackjack.  Just six days after Tony Romo broke up with Jessica Simpson, leaving her devastated, the Dallas Cowboys quarterback was spotted cruising the casinos in Lake Tahoe, Calif., on Wednesday.

‘Harry Potter’ at the century mark  —  Wiz makes $100 million appear  —  Warner Bros.' “Harry Potter and the Half-Blood Prince” won the opening day Quidditch match at the worldwide box office, jumping the $100 million mark in its first 24 hours.  —  Pic cumed a potent $58.2 million domestically …

Second person dies after Madonna stage collapse  —  (CNN) — A second person has died during construction for Madonna's upcoming concerts in Marseilles, France, authorities said Friday.  —  The second fatality was a 32-year-old British citizen, the British Foreign Office and a high-ranking police official said.

A Hollywood Blogger Feared by Executives  —  Right now, there's a good chance a Hollywood executive is leaning into a colleague's office and quietly asking, “Did you see what Nikki just wrote?”  —  That would be Nikki Finke, a well-traveled newspaper reporter who has found her moment as a digital-age Walter Winchell.

SPECIAL FRIEND  —  BRITNEY Spears (above) is supposedly dating her agent, Jason Trawick — so what is she doing spending so much alone time with record producer Dallas Austin?  A source tells us Spears and Austin spent some time together “two weeks ago at Dallas' house” in Atlanta, where, “It was just the two of them for a few nights.”

Tom Colicchio and Lori Silverbush Are Expecting!  —  Tom Colicchio was obviously thrilled to hear that his hit TV show Top Chef garnered two Emmy nominations Thursday morning - “It feels great!”  - but the award-winning chef admits he's a bit preoccupied these days: his wife is expecting a baby!