[Lilux-help] Debian testing & keyboard layout

Hi, I only just installed Debian testing (sarge) on a nice quick PC. This PC features the usual swiss french keyboard. Now, I've told the system via kbdconfig to configure this keyboard as what it is, i.e. swiss french, same for X11 (pc105 fr_CH). So the keymap got changed, I do have a swiss french layout - but for some reason, the Umlauts and accents don't work (keys between normal letters and enter). I've tried reconfiguring the locales, didn't help. I'll bet it's something very very stupid I'm overlooking... Does anyone have an idea what to look for to solve this problem? Greets & thanks, Eric