The reviews of Mel Brooks's new Broadway musical "The Producers," based on his outrageous 1968 movie comedy, are in, and they are all raves --- not just from the professional critics, but from the all-star crowd that attended Thursday's splashy opening night, reports PEOPLE. "Do I think Mel Brooks is funny?" Alec Baldwin bellowed when asked by PEOPLE. "You mean, that offensive, vulgar, disgusting, nasty, tasteless Mel Brooks? Yeah, I think he's incredibly funny! That Mel Brooks is funny!" Similar sentiments were echoed by other first-nighters, including Kathie Lee Gifford, Glenn Close, Joan Allen, Larry King, Harry Connick, Jr., Eric McCormack, Demi Moore, Mary Tyler Moore, Michael J. Fox, Lauren Hutton and Sarah Jessica Parker, whose husband Matthew Broderick costars in the show with Nathan Lane. Asked what makes Brooks so funny (he co-wrote the show's book and, by himself, the entire score), "Monty Python" vet Eric Idle told PEOPLE, "He's hysterical because he had an unhappy childhood, like everybody else."