There is a rematch clause for Haye, but Haye has better fish to fry and it does not look a good sell. The better match is Valuev v a Klit, and Haye v a Klit around the same time, and if both Klits don't win the winners could unify.
I don't really think he wants to fight any of the three no matter what is quoted coming out of his camp.
While I think Haye didn't deserve the decision against Valuev last go, I think he would be much more confident this time, and it would be a better fight.