Kevin Smith borrows Seth Rogen and a few other actors from the Judd Apatow stable for "Zack and Miri Make a Porno," a blend that makes sense.

Apatow has had the movie career that some of us envisioned for Smith when we first saw "Clerks," the funny, vulgar but secretly sweet indie that made Smith famous.

"The 40-Year-Old Virgin," after all, is "Clerks" on a bigger, more polished scale - the retail serfdom, the regular guys with their foul-mouthed bonhomie, an arrested-development character still immersed in the pop-culture trappings of childhood, and the ultimately sweet message about the search for love. And Apatow's other popular titles would have been right up Smith's alley - a movie about kids buying beer, a movie about losers smoking dope.

Smith, though, hasn't expanded on "Clerks" so much as he has remade it, sticking close to North Jersey, reprising the same characters and sticking with the same actors.

"Zack and Miri," though, feels like a fresh move for the director, who leaves Jersey for snowy Pittsburgh and recruits some new talent that helps give Smith's movie a different rhythm and feel.

Rogen is Zack, a coffee-shop clerk who shares an apartment with Miri (Elizabeth Banks) - a relationship that's platonic in the worst possible way. They have all the downside of cohabitation (they bicker over unpaid bills and dirty clothes and bathroom privileges) and none of the benefits.

When the utility company shuts off the power, Smith's plot commences. Zack and Miri need money, and when they bump into a gay porn star (Justin Long) at a high-school reunion, they hit upon an idea - why not make our own amateur porn movie and sell it?

Smith goes for, and gets, some "Ed Wood" laughs as Zack and Miri assemble a team of amateur actors and filmmakers (some of Smith's Red Bank ensemble turn up).

The focus, though, stays on Zack and Miri, slated to have sex on camera, an emotionally fraught event complicated by their buried feelings.

It's classic Smith: superficially dirty, but with an ultimately PG message about love and meaningful sex. Most of the meaningless sex is off-loaded to the lesser players, who include some actual porn stars (including Traci Lords, who proves once again that merely placing her in a movie isn't as funny as John Waters thinks it is).

Smith remains better at foul-mouthed comedy than emotional sincerity. Rogen is a fresh face for Smith, but he brings his own baggage. There are those who found Rogen to be an unconvincing match in "Knocked Up" for Kathering Heigl, and "Zack and Mia" will not erase lingering doubts about his suitability as a romantic lead.

In fact, the Rogen-Banks main event reminded me of something Rogen's character says in "Virgin" about a live show he witnessed in Tijuana involving a woman and horse.

"We think it's gonna be awesome and it's not as cool as it sounds like it's gonna be.

"It's kinda gross." *

Produced by Scott Mosier, written and directed by Kevin Smith, music by James L. Venable, distributed by Weinstein Co.