Ewan McGregor: Stocking cap or hairstyle?

Ewan McGregor's hair sticks out at unusual angles during a press appearance at the 2009 Sundance Film Festival for the film Thank You Philip Morris. The date was January 19, 2009. It's wintertime in Utah, so the question is: Is that a very expensive and stylish movie-star haircut, or did he just pull off a stocking cap?