caspert_ghost: do you mean that the language changes based on the forum user is in? I don't know a MOD that does that, but I do have a forum myself with different language forums within it... just basically named them French and Spanish and that is basically what people talk there. Seems to be working like that. With subforums, you could just add subforums for certain languages under a certain forum. For example:
Subforums: Chinese, Finnish, French, German, Italian, Japanese, Portuguese, Spanish
The forum itself would be in English of course, unless you install a MOD that sniffs the language of the browser user is using... there is also a MOD that adds a dropdown box where you can choose the language to use as a guest. Can't remember the names of the MODs, sorry.