Tuesday March 14, 2005 12:00 AM ET

When friends of Ashton Kutcher gathered recently for a night out at the new Hollywood hot spot he owns, the Geisha restaurant, they were astounded when the 27-year-old star dropped a bombshell: Demi Moore, 42, his beautiful girlfriend of almost two years, is pregnant! "Halfway through the meal, he told us there was a baby on the way," says a stunned source. In fact, Star has learned that Demi is eight-weeks pregnant, with a due date some time in October.

Demi received the happy news March 4, at an appointment at the Beverly Hills clinic, Woman's Care. She sat there "completely stunned," according to a friend. "She broke into this huge grin and you could tell she was absolutely thrilled." At first, she was afraid to tell anyone - even Ashton! But after calming down, "she absolutely couldn't wait," the friend says. "And when she got him on the phone, she blurted, 'Honey, I'm pregnant!'" Demi, says the friend, said the baby is exactly what she and Ashton had wanted. And there are already tell-tale signs that Demi is expecting. At the premiere for Ashton's new movie 'Guess Who,' the heavy-smoking actress didn't even take a puff, and sipped water instead of her usual caffeinated energy drink, Red Bull.

Even though the news is traveling fast in their social circle, Demi's keeping mum - at least in public - about being a mom again. That's not so surprising, as she suffered a painful miscarriage in 1997 in the final days of her marriage to Bruce Willis. And even Ashton, when asked publicly about his impending fatherhood at the Hollywood premiere of 'Guess Who,' denied the pregnancy. Was this at Demi's request? "Demi won't officially announce it until the third month of her pregnancy," says a source. "She's superstitious because she lost a baby before."

For more details on Ashton & Demi, check out Star, on newsstands beginning this Thursday.