Kevin Smith gets raunchier with his new film, `Zack and Miri Make a Porno'

Director Kevin Smith treated his fans to some adults-only material at the Comic-Con comic book convention on Saturday.

The writer-director _ a cult favorite _ showed footage from his new film, "Zack and Miri Make a Porno."

He said the comedy starring Seth Rogen, Elizabeth Banks, Justin Long and Traci Lords has been rated NC-17 by the Motion Picture Association of America. Smith called that rating, which prohibits children under 17 from seeing the film, "disappointing." He said he hopes to have it revised to an R rating, which allows children under the age of 17 to see a movie with a parent or guardian.

"I didn't feel it …