TINSELTOWN SPYWITNESS.

Byline: Elizabeth Snead and Joel Stratte-McClure

CATTY BEHAVIOR: Cat clothes for dogs? Oh, how embarrassing for poor Fifi and Fido.

Cats and dogs are natural enemies no more. Hello Kitty just launched its Little Lilly line of doggy sportswear Wednesday at Monroe's in West Hollywood. Naturally, there's more than just dog sportswear, pajamas and boots (yes, boots). You can also buy Hello Kitty dog carriers and beds. Can pink hair dye be far behind?

Tori Spelling came to the dog party with her pug, Mimi La Rue. Ahmet Zappa brought his and wife Selma Blair's mixed-breed pooch, Wink. Kathy and Rick Hilton, Marla Sokoloff, Courtney and Ashley Peldon, and Constance Zimmer were poochless on the pink carpet.

But they still had fun checking out the dog bowls decorated by Lindsay Lohan and Britney and Jamie Lynn Spears. The bowls were part of an online auction that also included a Hello Kitty Beach Cruiser bike and a TV/DVD. Proceeds benefited the Much Love Animal Rescue Foundation.

What's next? Hello Kitty pink condos and town homes?

PARTY, PART I: Forget Marilyn Monroe's breathy ``Happy birthday, Mr. President'' sung to John F. Kennedy.

That's nothing compared to Mary J. Blige singing a soulful and sexy rendition of ``Happy Birthday'' to Steve Stoute at his recent star-studded 35th birthday party.

Jay Z hosted and Reebok sponsored the birthday boy's bash at the trendy Hollywood Cabana Club, formerly the Sunset Room, now remodeled with lots of cabanas and bridges going over a huge pool.

The guest list included Will Smith, Henry Simmons, Nicky Hilton and her steady, Kevin Connolly, Shane West, Michelle Rodriguez, Cris Judd, Jermaine Dupri (the latter two in all-white outfits), Heavy D, comedian Tracy Morgan, Jason Davis and Blu Cantrell.

So who's this Steve Stoute and why should you care? He's a former hotshot manager turned powerful entertainment-marketing mogul, that's who. He's the man responsible for hooking up Beyonce with Tommy Hilfiger for her perfume, Justin Timberlake with McDonald's, Jay Z with Reebok for his S. Carter shoe line and 50 Cent with Reebok for his G Unit footwear.

So now you know. And admit it, you really do care.

PARTY, PART II: Happy birthday to Jessica Simpson, who turns 25 on July 10. She's having a private birthday bash Saturday at an undisclosed private L.A. residence with family, including hubby Nick Lachey and sister Ashlee, and lots of fabulous, famous friends.

Remember Nick's wild birthday party, held at the Hard Rock Hotel and Casino in Las Vegas? Well, away from the prying eyes of the press, Jess' may be even wilder!

Our spies say that Jessica's lucky VIP gal guests (like Eva Mendes, who's definitely made the list) will receive Hard Tail roll-down yoga pants and vintage tattoo print tanks in their goody bags. Gosh, we thought the birthday girl was supposed to get, not give, presents!

Jake Gyllenhaal is reportedly high on the boy guest list. He's been seen out and about recently looking tres affectionate with his ex, Kirsten Dunst. So we shall see if they show up a deux or whether he prowls the party solo.

Wonder if Lindsay Lohan's on the guest list. Probably not. But Lindsay, even if Ashlee IS dating your old boyfriend, buck up and go, if only for the Hard Tail togs, a cult fave among L.A.'s lithest ladies.

IN A `HAPPY' PLACE: Lisa Kudrow is best-known for her comic roles: lovable Phoebe on ``Friends'' and now, Valerie Cherish on HBO's ``The Comeback.''

But she explores her darker, dramatic side in ``Happy Endings,'' a quirky new black comedy written and directed by Don Roos, who first directed Kudrow in ``The Opposite of Sex.''

Kudrow choked back tears at the closing night of the Los Angeles Film Festival screening last Sunday when she publicly thanked Roos for the chance to play Mamie, an emotionally scarred woman who gave up an out-of-wedlock child as a teenager.

Turns out that Roos wrote the role just for her. And Kudrow admits that she's never before played such a damaged character.

``Mamie is a woman who believes she's in control of her life and she's really not,'' Kudrow reveals. ``She gets to that point where everything is stripped away from her and she doesn't have a choice but to confront her secrets.''

The film, which opens on July 15 in limited release, weaves multiple stories to create a unique, bitingly honest and amusing look at love, family and the unpredictability of life with a gold mine of buried secrets, missed opportunities and second chances.

FOLLOW THE BIRDIE: You could almost call Robert Redford's next film project an ``in-flight'' movie.

The environmental activist/filmmaker/actor will star in ``Aloft,'' an upcoming National Geographic feature film. Redford will play a retired eccentric pilot who, along with an obsessed naturalist, doggedly tracks an endangered falcon.

``Aloft'' is based on ``On the Wing: To the Edge of the Earth With the Peregrine Falcon'' - a true story of author Alan Tennant's adventures/efforts tracking Amelia, a wily female falcon (named for Amelia Earhart) as she flies from her Texas coast winter hangout to her summer Arctic nesting grounds.

No word yet on who will play Tennant's role: a would-be scientist obsessed with the Tundra peregrine. But it's no wonder Redford optioned it. Movie marketing guru Harry Clein compares the new bird-brained buddy movie to ``Butch Cassidy and the Sundance Kid'' because of its frantic transcontinental race, filled with close calls, fake IDs, near disasters, not to mention run-ins with the military, the cops, the Royal Canadian Mounties, some Mexican Federales and a few Guatemalan guerrillas.

Can you say, ``Who are those guys?''

CAPTION(S):

4 photos

Photo:

(1) SPELLING: Hello Kitty - and doggie.

Lester Cohen/WireImage.com

(2) BLIGE and STOUTE: A birthday serenade.

Mark Mainz/Getty Images

(3) KUDROW: Another role to cherish.

(4) SIMPSON: With age comes wisdom. Usually.

Steve Granitz/WireImage.com