The actress - who turned 41 October 28 - has no intention of reprising her role as prostitute Vivian Ward in a follow-up to the hugely popular film, because she thinks she is too old.

Asked whether she would ever consider reuniting with former co-star Richard Gere for a sequel, Julia replied: "I don't think so! No one wants to see an old hooker, do they?"

Julia celebrated her birthday early on Monday night in San Francisco restaurant Jardiniere, accompanied by husband Danny Moder and celebrity pals including Tom Hanks and Rita Wilson, Bruce Willis, Sean Penn, Robin Wright Penn, Billy Crystal and Jack Nicholson.

Diners inside the exclusive eaterie reported the star-studded table sang 'Happy Birthday' to Julia and to Rita, who turned 52 on October 26.

Julia - who paid tribute to late actor Paul Newman with a reading at The World Of Nick Adams event earlier that evening - also explained the odd patch of pink hair she was sporting.

She said: "Well, my daughter Hazel said, 'Mommy, I wish you had pink hair', and I said, 'Well, I don't know if all of it would look nice', so I just did a little patch!"

Julia and Danny have three-year-old twins Hazel and Phinneaus and a 16-month-old son Henry together.