Danielle Staub is being sued for $5 million by ex-husband Kevin Maher, who says her allegations of rape and other insults against him are defaming.

But Staub has now taken legal action in return, making the same case THG makes any time Larry Birkhead sends us a letter complaining that we're harming his reputation via a few negative articles: you do that all on your own, pal!

In documents obtained by TMZ, Staub says Maher has "no evidence" that Danielle said anything especially bad about him. Moreover, even if something did slip out of her mentally unbalanced mouth... so what? Maher has already stuck a foot deeply into his own.

In "Cop Without a Badge," the book that exposed Staub's drug-dealing past, Maher admits to the following:

* He used cocaine.
* He has "overactive sexual proclivities."
* He once shoved a gun into the genitals of a man he thought was banging Danielle.

For once, therefore, Staub might actually have a point: how can anything she says defame the reputation of a man that has already owned up to these actions?

Kelly Brook got a nice fright during the production of the horror film "Piranha 3D," but it had to do with the fuzz, not fanged fish. Brook tells us that during a break in filming, she and co-star Jessica Szohr decided to drive from the film's set in Lake Havasu, Ariz., to Las Vegas for a little R&R, but ended up lost late at night at the Hoover Dam.

"The next thing I know, there are three police cars following us," says the British Brook. "In England, the natural reaction is to get out of the car and ask for directions, which is what I did," she explains. Unfortunately, she says, this prompted the cops to jump out of their squad cars with weapons drawn.

Brook, who bares all in the film, which opens Friday, and on the pages of this month's Playboy, says: "Next thing you know, we have got our hands on the bonnet [hood] of the car and we're trying to assure [the police] we're just actresses on our way to Vegas.

"To have a gun pulled on you and then be asked for your autograph in the space of a minute is just a bizarre turn of events." Yes, but we bet those cops went home happy.

While Robin Thicke's lovely wife, Paula Patton, was filming her guest role on "Law & Order: Special Victims Unit" at the Empire Hotel on Monday, the singer had domestic chores to do. A source tells us Thicke was in the upper West Side hotel's Lobby Bar, interviewing nannies for the couple's 4-month old son, Julian Fuego. Don't put those résumés away just yet, ladies and gentle-mannies: There's no word if any of the "handful" of aspiring caregivers won over the "Sex Therapy" crooner.

Johnny Weir can take a few insults, but don't upset his mom. The Olympic skater tells us he wasn't thrilled with how New York magazine portrayed him in its current issue, but what really cheeses him off is that his mother "was offended" by the feature.

"She said it seemed I wasn't serious and I was just another New York-area person just going to parties," Weir says, before explaining: "Yes, I was getting ready for red-carpet events, but I was going to them to work and network." Weir also grouses that the feature "attacked my people. ... I can be told to be subjected to a gender test, I can have my clothes attacked, but when you attack my people, my army, that's when I get pissed off!"

A spokeswoman for New York magazine responds: "We love Johnny Weir - as Amy [Larocca] writes in the piece, he's ‘talented and clever and beautiful,' and we think that comes through in the profile and photos."