Searching and accents

I can hardly imagine that nobody ever ran into the same problem, but I can’t find a thread about it, so here we go.

When I use names or words with accents in a post (such as Dumézil, Dernìère Volonté, Nōvy Svět, etc.), posts with these words will not be given if someone searches for “dumezil”, “derniere” or “novy svet”. Is there a way to overcome that, a plugin perhaps (that works with 2.3.1)? I haven’t found one, but I hope there is one, or another sollution.