Duokan, no french hyphenation

Hi

I have problems using Duokan (with french books, haven't tried with english ones...).
I have justification enabled, and while it seems to do what it can to properly justify text, it doesn't really work, as it never splits words.

I guess I miss an hyphenation dictionary or something (just enabling this option, but its maybe not translated...), any help welcome.

Btw im using latest Duokan version (2014/01/03).

Thanks