[Haskell-cafe] Constraing satisfaction

Hi. I have a set of problems in the field of constaint satisfaction and I'm looking for a tool for this. In simplest form, these task are like Sudoku puzzle solver, school schedule creator, etc. Prolog language comes to mind at first. But if to choose Haskell? Can be these tasks defined in Haskell with the same elegance as in Prolog, or I'll need some additional framework or library?