Rosie O'Donnell's mouth might have helped land her in court, but once she got there, it was her stomach that caused the real trouble. Moments before the Oct. 30 start of her trial over the demise of Rosie magazine, "I threw up," says O'Donnell. "I used to do that as a kid before a big test."

Indeed, this court battle is shaping up to be O'Donnell's biggest test yet. After she left the publication in September 2002 during a power struggle with publisher Gruner + Jahr USA, the company sued O'Donnell for $100 million, claiming that she walked away without legal justification. O'Donnell, 41, responded with a $125 million counterclaim, contending that G + J usurped her editorial control and inflated sales figures to keep her from terminating the venture earlier. In the trial's first three days, G + J witnesses painted her as a prickly boss who demanded her own way and sometimes cursed out employees who disagreed with her. Even so, says O'Donnell, "I am confident that when the facts come out, the judge will find in my favor." (Both sides waived the right to a jury.)

Even before presenting her side, however, O'Donnell—clad each day in brightly colored outfits and accompanied by her partner, Kelli Carpenter, 36—began striking back in daily postcourt press conferences. Responding to a G + J claim that she had tried to adopt an edgier persona after Boy George told her she was "too suburban" to bring his musical Taboo to Broadway, O'Donnell quipped, "Do you really think I'm going to change my whole life because of a comment Boy George made? It's something I said on Leno! As comedy!"

The testimony of several former Rosie staffers wasn't so funny. Susan Ungaro, a consultant who helped launch the magazine in April 2001, said that O'Donnell—who was Rosie's editorial director—was a strong editor but "can be very difficult to get along with." And Cathy Cavender, Rosie's initial editor-in-chief, said that while she often enjoyed working for O'Donnell, she was afraid to disagree with her too much, lest she be fired. "Rosie was pretty sensitive," said Cavender, "and some discussions I thought were in the normal give-and-take of business seemed to rankle her." Even O'Donnell's lead attorney, Lorna Schofield, conceded that her client can be demanding. "She is not Mother Teresa," said Schofield in her opening statement. "She's loud. She has a temper. And when she's provoked, she yells and curses."

However, it was Susan Toepfer, who was hired to replace Cavender in June 2002 (and is a former PEOPLE editor), who painted the darkest picture of O'Donnell. During her testimony Nov. 3, Toepfer said that just two days into her job, after selecting a Rosie cover photo featuring O'Donnell and Sopranos stars Lorraine Bracco and Edie Falco, she received a blistering phone call from the comic. "You are about to hear a Rosie you've never heard before, an angry Rosie," Toepfer said O'Donnell told her. "You're trying to destroy me! I don't want my fat f—-ing body on the cover." (The cover ultimately ran without O'Donnell.)

Later, said Toepfer, O'Donnell threatened, "If I am not the boss of this magazine, I will bring it down," and voiced reservations about appearing on future covers with female celebrities: "As a lesbian, I am not comfortable being on a magazine cover holding another woman." O'Donnell denies the claim: "I have never in my life said, 'As a lesbian,'" she says. "'As a lesbian, pass the salt. As a lesbian, blah blah blah.'" O'Donnell's case, Schofield says, will show that G + J purposely inflated sales figures—keeping losses just below $4.2 million in its first year—to prevent triggering a clause that would have allowed O'Donnell to walk out on the contract earlier.

Even if the trial does not end on Nov. 12, as most predict, it will not push back the Nov. 13 Broadway opening of Taboo, the musical based on the life of Boy George, who costars and wrote the music and lyrics (O'Donnell is bank-rolling the entire $10 million production). "It's a hard thing to do both," said O'Donnell, who nonetheless is looking forward to finally taking the stand herself. "I will tell the truth and let the judge decide," says O'Donnell, who says she will give any trial winnings to charity. "The trial is not over yet. We'll see who's standing at the end."

JASON LYNCH
Mark Dagostino in New York City