''The Simpsons'' are a cash cow

With fame comes diversification: Bart Simpson, riding a wave of celebrity in Fox’s The Simpsons, not only has a featured role in a big lawsuit (courtesy of Tracey Ullman), but he’s about to star in his first feature film. According to series creator Matt Groening, plans are afoot to bring Bart and family to the silver screen. ”We’ve talked about it,” he says. ”I’m sure it will happen (but) there’s no story yet. We plan so much story into one half hour that it’s hard to figure out how to take advantage of the (movie) medium.”

If a film is made, former Foxmate Ullman will undoubtedly be seeking a share of the profits. The actress, whose variety show spawned the animated series, claims Fox has deprived her of a promised 5 to 10 percent of Simpsons marketing receipts. (”I breast-fed those little bastards!” she joked on last year’s Emmy awards telecast.) If Ullman wins, her cup should runneth over: Fox reportedly earned over $50 million from Simpsons merchandise in 1990.