Who's the daddy: Pregnant Jamie Lynn Spears dumped by boyfriend who demands proof of paternity  —  Pregnant Jamie Lynn Spears has been dumped by boyfriend Casey Aldridge because he doubts he is the father, it has been claimed.  —  Aldridge is insisting that TV star Jamie Lynn, 16 …

Rep: Rocker Avril Lavigne Not Pregnant  —  Jennifer Aniston isn't the only celeb debunking pregnancy rumors.  —  A rep for Avril Lavigne tells Usmagazine.com the rocker is not expecting.  —  Citing an “insider,” Canadian radio host Zack Taylor wrote, “Avril is a month-and-a-half pregnant …

Katie Holmes: Nicole's Pregnancy is ‘Wonderful’  —  Katie Holmes only had well wishes for Nicole Kidman Wednesday night at the Los Angeles premiere of her new film Mad Money.  —  “I'm so happy for her,” Holmes, 29, says of Kidman's pregnancy news.  “It's wonderful.”

New Video: Britney Leaves the Country!  —  “The Insider” has the latest on the pop princess.  —  Check out the latest footage of BRITNEY SPEARS and her new paparazzi pal ADNAN GHALIB!  Despite rumors that the pop singer flew to New York, “The Insider” has learned that she drove down to Rosarito Beach, Mexico, Wednesday with Adnan.

Brit's Ultimate Fake-Out  —  Britney Spears hoaxed us all out — sending out the word she was winging her way to NYC, but HOLA ... she's in Mexico.  —  Video has just surfaced showing Brit driving around Mexico with Adnan, her new BFF/paparazzo.  This followed an elaborate fake-out involving Brit's people …

Sheriff vs. Judge in Michelle Rodriguez Case  —  A war of sorts seems to be erupting between the L.A. County Sheriff's Department and some L.A. County judges on the subject of incarcerated celebs.  —  “Lost” star Michelle Rodriguez was released yesterday, after serving only 10% of her sentence.

Side Dish  —  Golden girl Tyra Banks says that despite fame and fortune, she's a bird in a gilded cage.  “I'd go to work [on 'The Tyra Banks Show'], and women would be crying in my arms,” she tells the latest issue of Essence, on stands Saturday.  “But then I'd go home and put my key in my door and ... nothing.

KIDD ON THE WAY  —  NEW Jersey Net Jason Kidd is having another kid.  A year after his messy split from wife Joumana Kidd, sources told The Post's Hasani Gittens that Kidd's “model” girlfriend, Hope Dworaczyk, is expecting.  “Hope, Jason and their parents all celebrated...

Kathy Griffin — Undercover Without Cover  —  Kathy Griffin scared the crap out of people during a recent appearance on radio, and it had nothing to do with what she said.  She showed up sans makeup on Adam Carolla's morning radio show, lookin' interesting — not necessarily bad, just not at all like Kathy Griffin!

Coroner: Donda Had a Heart Attack  —  TMZ has just received the final coroner's report on the death of Donda West.  The L.A. County Coroner has concluded that Kanye's mom died of “coronary artery disease and multiple post-operative factors due to or as a consequence of liposuction and mammoplasty.”

ADRIAN GRENIER PICKUP LINES: A PLAY IN ONE ACT  —  [Scene: A crowded loft on Manhattan's Lower East Side.  It is approximately 2:00 a.m.; the party is now winding down, though the bar is still open and people are still drunkenly—badly—dancing.  In walks Entourage star Adrian Grenier …

Joel's Big Bro: Nicole Richie Due ‘In The Next Week’  —  The countdown-to-baby has begun for Nicole Richie and Joel Madden.  —  Their first child is due “sometime in the next week,” Madden's older brother Josh told reporters at the FUZE/Resolution Slenderize bash in Hollywood Wednesday night.

Pam to Rick — I'm Pregnant, Get Lost!  —  TMZ has learned the divorce between Pam Anderson and Rick Soloman is back on and Pam is pregnant!  —  You'll recall Anderson filed for divorce last month, but called it off just days later.  But sources tell TMZ she is now moving forward with the divorce …

A Key To Britney  —  Here's that OK!  Magazine cover (of her and her boys) that Britney was not happy about.  —  But take a look closer...  ...at that pink-beaded bracelet with a key (that has the number “6” on it) attached.  Guess where that key's from?  The Spa at the Four Seasons Hotel!

Halle Berry: ‘I Want to Stay Pregnant Forever’  —  Pregnancy certainly suits actress Halle Berry, whose first child is due in March.  —  “My skin is aglow from all the hormones,” the Oscar winner and star of the upcoming Class Act, 41, tells InStyle in its February issue.  “I want to stay pregnant forever.”

Lindsay & Adrien: It's On!  —  Things between Lindsay Lohan and Adrien Grenier are heating up!  —  Lohan was first spotted at the Entourage star's New York City apartment last month.  —  “They're talking,” says a source close to the pair.  And by talking we're sure they mean “f**king.”

Amy goes Back to Blonde as she ditches her brunette beehive  —  Her brunette beehive is as legendary as her shambolic lifestyle and jazz diva voice.  —  But when Amy Winehouse stepped out to the shops yesterday, she had ditched her gravity-defying barnet for a startling bleached blonde hairdo.

Biel extols ‘Virtue’ for Endgame  —  Jessica Biel has been cast as the lead in the romantic comedy “Easy Virtue,” based on the Noel Coward play, for London-based Ealing Studios.  —  Endgame Entertainment is financing the indie project.  —  Biel plays an American divorcee, Larita Huntington …