From the web site:

  Tuareg is a Caml mode for GNU Emacs and XEmacs. It handles automatic
  indentation of Objective Caml and Camllight codes. Key parts of the
  code are hilighted using Font-Lock. Support to run an interactive
  Caml toplevel and debbuger is provided.

  This mode attempts to give better results than the one provided in
  the standard distribution OCaml 3.x. Indentation rules are slightly
  different but closer to classical functional languages.

  There is no relation with the Tuareg People, except their reputation
  of great CAMEL riders and breeders.

Documentation is installed into share/doc/tuareg-mode

WWW: http://www-rocq.inria.fr/~acohen/tuareg/