Joe Namath has become a grandfather, perhaps a bit sooner than he'd planned.

The football great's daughter Olivia has had a baby girl at 16.

"She was pregnant at 15," says a source. "He claims to be thrilled."

Indeed, the former New York Jets quarterback - who's currently living in Tequesta, Fla. - told top Palm Beach Post columnist Jose Lambiet: "I'm very happy."

Still, Namath's ex-wife, Tatiana, will raise the infant, who is now 2 months old, says the source.

"Tatiana came and picked up the baby and brought her back to California, where she lives," the source added. "Olivia's going to stay with Joe and her sister Jessica in Tequesta, where she's still going to high school."

Edwin Baker, age 19, is the name of the father listed on the birth certificate. An Edwin Baker, 19, of nearby Jupiter, Fla., has been arrested three times in the past year on charges of possession of crystal methamphetamine, grand theft and burglary.

Neither Namath nor his attorney returned our call for comment.

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Billy Joel can't enjoy concerts because he's too famous.

"I went to the Dave Matthews [Hampton Social @ Ross] concert, but I didn't get to hear that much of the show," Joel told us at a Hamptons magazine party Tuesday night. "I was trying to hang out and be a fly on the wall, but I kept getting accosted by fans wanting pictures, so I had to split. I felt kinda bad."

So what did he think of the concert series that he was a part of? "Well, usually private gigs kinda suck. The people aren't fans; they pay too much money; there's too many distractions and everyone's too cool to be enthusiastic. But [the Social] gig wasn't bad."

That doesn't mean the Piano Man would have forked over the $3,000 ticket price for the show, though. "I'd only pay that much for the Beatles or Jimi Hendrix," he quipped.

Joel was at the Hamptons mag party to help fete his wife, Katie Lee Joel, who recently graced the publication's cover. While mag owner Jason Binn led the introductions at the Hudson Hotel event, Joel also shared with us that he reads this column. "If I'm in there, I'll read it," he said. "Katie reads it all the time. I'm more of an editorial pages man myself."

Katie, a chef by day, is no stranger to the celebrity lifestyle. She hosted "Top Chef" during season one and has a cookbook, "Comfort Table," coming out in 2008. But given her choice of things to do, she'd rather sit at home in her sweatpants and watch TV.

Said Katie: "We love ‘Entourage.' We're glued to the TV set on Sunday nights at home."

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Justin Timberlake was bringing Bar 89 back Tuesday night. The singer was at the SoHo restaurant to celebrate a band member's birthday and, according to a spywitness, looked "laid back and calm" despite his sold-out shows at MSG last night and tonight.

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James Blunt, 33, was “constantly hovering” around Mischa Barton, 21, at an Estate event August 11 in Sag Harbor, New York, a witness tells Us Weekly.

“He’s obsessed with her and has been trying to get with her for a while,” adds another source.

Alas, a Barton pal says the actress “just wants to be friends.” Ouch!

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CELEBRITIES apparently can wait longer than the rest of us to pick up petty cash they're owed. The state of Florida has heaps of unclaimed cash, stock refunds and security deposits waiting for folks like Britney Spears, Justin Timberlake, Burt Reynolds and Joe Namath, the Palm Beach Post reports. Spears has yet to collect an $828.29 check for a video she made before she got famous, while Timberlake has $2,600 lying around, including a paycheck from Disney. Reynolds hasn't claimed $2,000, including $1,300 from Universal Pictures, and Namath has $83.52 in Disney shares that are his to grab. Celine Dion's family is owed an old Direct TV deposit, and late Bee Gees star Maurice Gibb is due $856.18 in copyright money. Also owed: Tiffany Trump, Donald's daughter with Marla Maples, to whom Tiffany & Co. should have sent a refund of $36.19, but forwarded it to the state instead. Rick Sweet of Florida's Bureau of Unclaimed Property explained to the paper: "Some [celebs] are moving around a lot, and the money may not be substantial enough to file a claim."


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THEY call MTV's "The Hills" a "reality" show, but we've had our doubts for some time. Fueling our skepticism, on Tuesday night, the star, Lauren Conrad, showed up at Da Silvano for dinner with three friends and a camera crew. One irked diner told us, "It was clear that this show is not a reality show. They took five takes of Lauren ordering dinner. The film crew took over the outside eating area by setting up lights and cameras everywhere. They should go back to California."

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SHE'S been shy about bearing her bod every since her racy Gear magazine spread hit stands in 2000, but Jessica Biel plans to shed her threads in the upcoming movie "Powder Blue," which co-stars Forest Whitaker. Us Weekly reports that she'll play a "stripper trying to earn money to raise her terminally ill son," and audiences will get an eyeful. Biel "signed a contract that explicitly details the bare minimum fans will see - including shots of her breasts and butt," a source dished to the glossy.

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Jennifer Aniston is in final negotiations to star in "He's Just Not That Into You," New Line Cinema's ensemble comedy being directed by Ken Kwapis. Drew Barrymore and Nancy Juvonen are producing via their Flower Films banner.

Aniston joins Jennifer Connelly, Kevin Connolly, Bradley Cooper, Justin Long, Ginnifer Goodwin and Barrymore in the Baltimore-set movie of interconnecting story arcs dealing with the challenges of reading or misreading human behavior.

Aniston will play a woman in a long-term relationship with a boyfriend who will not commit to marriage.

"Into You" is based on the best-selling book that is a social commentary about modern-day relationships and how men and women often misconstrue the intentions of the opposite sex. The book was written by Greg Behrendt and Liz Tuccillo, who worked together on "Sex and the City" as a consultant and writer, respectively. Abby Kohn and Marc Silverstein, who penned the Barrymore starrer "Never Been Kissed," wrote the adaptation.

Production is scheduled to start in early September in Los Angeles.

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We hear the rumor is true - Britney Spears is preparing for a "surprise" performance at the MTV Video Music Awards Sept. 9 in Vegas. One insider tells us Brit's recent meetings with manager Jeff Kwatinetz are geared toward fine-tuning her routine, and that her label is worried any missteps (or a no-show) could hurt her comeback.

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Nick Lachey will hang out with you, so long as you buy him a drink. At Butter on Monday night, a random male patron approached the singer and said, "I'm just asking flat-out: Would you take a shot with me so I can say I took a shot with Nick Lachey?" Nick was more than happy to oblige.