The producers of the hit series "Seinfeld" are developing a spinoff sitcom that would star Phil Morris, reprising his role as that show's slick attorney Jackie Chiles.

Morris surprised reporters at the television press tour today when he mentioned the new project in passing during a question-and-answer session for the BET cable network, where he will appear in an upcoming made-for-TV movie. He also surprised executives at NBC, where "Seinfeld" aired. This morning a spokeswoman said the network had no knowledge of the spinoff; by the afternoon, she said there had been informal conversations about the project, but no "formal meetings."

Morris's timing was unfortunate: BET Chairman Robert Johnson had just finished chastising the broadcast networks for failing to cast minority actors in lead roles on their prime-time shows--an issue that has been in the news since the NAACP announced earlier this week it is exploring litigation against the big four networks and boycotts of their sponsors. In his remarks, Johnson singled out "Seinfeld"--a show set in New York City but with an all-white regular cast--to illustrate how the broadcasters have ignored their "public interest obligation."

Morris, who is African American, then piped up with news of his program. The fact that the only "Seinfeld" spinoff in the works would showcase the sitcom's only black character shows that "if you're funny and good . . . you cannot be denied," he said.

Though Morris later told reporters that the project would be pitched to NBC next week or the following and that "Seinfeld" creators Jerry Seinfeld and Larry David were on board as executive producers, Castle Rock Television, which produced the hit sitcom, told a slightly different story.

According to Castle Rock President Glenn Padnick, Seinfeld and David have given their blessing to the spinoff, but have not agreed to be actively involved. The show does not yet have a writer, Padnick said, though he said that Andy Robin and Greg Karet, writing partners who worked on "Seinfeld" and who have a deal with Castle Rock, may take on the project. It will not be pitched to NBC in the next couple of weeks, but it definitely will be pitched to that network first, Padnick said.

If NBC doesn't pick it up, it will be pitched to other networks. But NBC would be nuts not to act. "Seinfeld" was for four years the most watched program on American television, and by its final season, 1997-98, it averaged 37.2 million viewers a week--numbers the network hasn't seen since.

It had been widely rumored that Castle Rock would try to develop a spinoff series to showcase Seinfeld's wacky next-door neighbor, Kramer (Michael Richards). Not so, Padnick said.

Regular characters Kramer, Elaine and George Costanza are too close to the original series to succeed as a spinoff. Also, the actors who played those parts all "have a great desire to separate themselves from those roles," Padnick said.

The Creative Artists Agency, which represents Seinfeld, did not return a call for comment.

The Chiles character, who appeared in only seven episodes of the series in its run from 1990 to 1998, is "not so much a part of the warp and woof of the original show," Padnick explained. The new comedy would have Chiles, who is said to be loosely based on Johnnie Cochran, working for an all-white law firm.

Though Chiles appeared in few episodes, they were all memorable. He was usually representing Kramer, in lawsuits brought against the tobacco companies, a coffee bar and Elaine's friend Sue Ellen Mishke, who distracted Kramer so much by wearing only a bra that he caused a car accident. Morris's character also appeared in the well-watched season finale, defending the entire cast, who were sent to jail.

But it was Honda that pushed the Chiles project forward. The car manufacturer bought the right to use the shifty attorney in a series of minivan ads. "People love them," Padnick said of the commercials. "They made us feel better . . . that the character could be the center of another show."

And though it was only the second day of the summer press tour, there was already a winner for this year's Foot-in-Mouth Award: diva Cher. Appearing via satellite for HBO to promote an upcoming concert for the cable TV network, she was asked if she had tried to prevent ABC from airing last year's Sonny and Cher film. Cher dismissed the project, saying, "TV is not exactly a place where you do films," which had the packed ballroom of reporters howling. "What's so funny?" she asked.

At the end of her Q&A, HBO honcho Chris Albrecht made light of Cher's gaffe, reminding viewers of the cable network's ad campaign, "It's not TV, it's HBO." Cher chimed in, "HBO's not television."

"Cher: Live in Concert at the MGM Grand in Las Vegas" will premiere on HBO on Aug. 29.

CAPTION: Phil Morris, left, as attorney Jackie Chiles in the "Seinfeld" series finale. He says a spinoff is in the works.