In season two, we learn that Phoebe ( Lisa Kudrow
) married her friend Duncan ( Steve Zahn), a gay Canadian ice dancer who needed a green card. He then seeks her out to get a divorce -- and informs her that he's actually straight and was just in denial about it.
Green-card marriages are so easy and worry-free that you don't even have to tell your friends about them.
-- Rick Porter, Zap2it