FOIL implementation with Haskell, Lisp, Erlang, OCAML, others ?

Hello guys, I've the opportunity to write a parallel version of the FOIL algorithm for an ILP system. I've the options to choose whichever functional language I want, what would you guys choose and why ? It's seems that erlang would be a good fit due to it's support for concurrency, Lisp with integration with PVM or MPI would also be a good option I think, but how about the others ?