Problem with accentuated characters

Hello,
I’ve installed WordPress and I think it’s a really cool blogging system, but I have a problem with the French accentuated characters.
Apparently, WordPress doesn’t convert them to HTML (à for à, for example). They still look fine on the weblog, but cause problems with the RSS files. They stop before the first accentuated character, saying an incorrect character has been found.
I didn’t find anything about this in the forums, but maybe someone could help me with that…
Thanks.
Brice.