>         you get the expected types in the answer, but each of them is
> prefixed by an underscore:

[English]
Have a look at the Caml FAQ:

http://pauillac.inria.fr/caml/FAQ/FAQ_EXPERT-eng.html#variables_de_types_faibles

[Franc,ais]
Regardez la Foire aux Questions du langage:

http://pauillac.inria.fr/caml/FAQ/FAQ_EXPERT-fra.html#variables_de_types_faibles

This must help a lot.

Pierre Weis

INRIA, Projet Cristal, Pierre.Weis@inria.fr, http://pauillac.inria.fr/~weis