(digitalspy.co.uk) - Comedian Joan Rivers has described Angelina Jolie as a "stupid actress".The American comic, who is currently performing A Work In Progress By A Life In Progress onstage in London, said it was a pleasant surprise to work with intelligent co-stars.She told GMTV: "I'm finding actresses are smarter than I thought. "Well I've worked with stupid actresses. I've worked with Angelina Jolie - she saw a sign that said 'Wet Floor' one time, and she did! "I mean she's attractive, but not a bright girl. Stunningly beautiful but stupid. She would have asked Stevie Wonder, 'What's your favourite colour?'"