`LETHAL WEAPON 4' ASSIGNMENT INCLUDES PARENTHOOD.

Byline: Marilyn Beck & Stacy Jenel Smith

Don't get the idea that Mel Gibson will be kicking back on ``Lethal Weapon 4'' now that hot young Chris Rock is joining the team.

``The lethal weapon is still Mel - it may be a little old and a little rusty, but it's Mel,'' reports director Richard Donner.

As it turns out, Gibson's action will not be restricted to his line of work.

``He's going to have a baby in the movie - with Rene Russo. They'll get married at the end of the film,'' reveals Donner.

And speaking of action, Rock will play a young cop who is expecting a child via the daughter of the character played by Danny Glover. ``Danny's character doesn't know about it,'' says Donner. ``If he knew about it, he'd kill her. Not because the couple isn't married, but because she married a cop.''

Donner has had three writers working on independent versions of the same story for six weeks. He plans to take the best from each of the screenplays and have a shooting script in three weeks.

Gibson still has to approve the final script, but Donner doesn't seem concerned about that. ``If we're going to do a fourth `Lethal Weapon,' it had better be sharp and witty. And, believe me, I can already tell you it will be.''

Shooting is slated to start Jan. 8.

The snow must go on

Dennis Quaid, who's starring in Sony's remake of ``The Parent Trap,'' reports that the troupe got caught in a snowstorm while shooting summer camp scenes this week in Southern California's San Bernardino Mountains. Quaid didn't mind. He says, ``I'm usually miserable on a set - shooting in some Eastern European outback in four feet of water. I'm not complaining about the snow or anything.''

The company already has spent a stretch in London, where Dennis was joined by his wife, Meg Ryan, and their 5-year-old son, Jack Henry, and in Napa Valley. Now it's on to L.A., where the film will wrap in December.

``It's better than working for a living,'' quips Quaid, whose career is definitely on an upswing. He co-stars with Danny Glover in the upcoming ``Switch Back,'' playing an FBI agent trying to track down a serial killer who's kidnapped his son. And he's directed his first movie, a modern-day western, ``Everything That Rises,'' which will debut on TNT in July.

Internetzzo

Self-proclaimed comedy goddess Judy Tenuta may have a slim figure, but she has an oversize mouth. Tenuta has a new talk show debuting today on the Internet. She claims, ``I couldn't be a talk-show host on television because I didn't make the weight limit.'' The caustic comic goes on, ``Oprah went under the weight limit and her popularity went down. ... Roseanne? She'll have no problem. She's out grazing right now, that cow.'' With sentiments like those, we can guess who'll be avoiding Tenuta's comedy/chat skein, which may be found at aentv.com. She taped all the shows ``in a wild blitzkrieg'' week at an L.A. comedy club - with ``pop icon'' guests including Gary Owens (``Laugh-In'') and Monty Hall (``Let's Make a Deal''), plus spoon players and other assorted novelty acts.

There (whoosh) goes the bride

The wedding of ``Beverly Hills, 90210's'' Hilary Swank and ``ER's'' Chad Lowe sounds like something out of a script. The actress relates that she and Chad had spent the better part of a year planning their Sept. 28 nuptials. Then, three weeks before the wedding, she was hired for ``90210'' - and the show went right into its notorious ``double-ups'' shooting schedule, in which two shows are shot simultaneously, with work days that can stretch beyond 16 hours. On top of it, construction on Hilary and Chad's home had not been completed as planned, and was still going on as relatives began arriving ``from all over the Midwest - Nebraska, Iowa, Ohio - for the wedding.''

Hilary, who plays single mom Carly on the Fox series, brought a few of her kinfolk onto the set to entertain them, then forged ahead with her work. Amazingly, the wedding came off as scheduled and was, she says ``The best day of my life.'' The ``90210'' production team even worked her schedule around to give her two days off. Says Hilary, ``People say to me, `Aw, it's too bad you didn't get to have a more of a honeymoon.' And I say, `It's OK! I'm working!' ''

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3 Photos

Photo: (1) Mel Gibson

Kicking back

(2) Dennis Quaid

No complaints

(3) Judy Tenuta

Can't weight to be caustic