@yoarts : Yes, I have the last version of WordPress installed. And the problem was present on the 1.5.1 version of the theme.
I updated to the 1.5.4 when it came out, but major problem : the menus no longers worked when the screen size was small enough to collapse the menus. So I reversed back to 1.5.2 (the last one on which menus were working).
I’ll try updating to the latest version.
