According to OK! magazine, Heath Ledger is in negotiations to star in a sequal to Brokeback Mountain. The story is about Heath's character Ennis, coming out of the closet and coping with being openly gay in 1963 Wyoming.

Heath's ex-girlfriend and baby mama, Michelle Williams, played his wife in the first movie, which is where they met and she got pregnant fell in love. No word if she's going to be coming back for the sequal, but I doubt it. Jake won't be coming back (obviously), because his character died in the first one. Sorry to spoil it for those who haven't seen it, but it's been a couple years already. You should have.

Source