[Haskell-cafe] upgrading Text.Printf

Hi, I am using Text.Printf (package base, ghc-6.6.1) and am missing %X formatting. Checking out the darcs repo of the base package I see that it has already been added there. Is there any way to upgrade to the latest version while keeping ghc-6.6.1? I keep hearing Bulat saying that this is not possible, but I wanted to check anyway. Is there, perhaps, a separate package that contains (a newer version of) Text.Printf? Cheers Ben