Comment 17 for bug 852485

By the way, by google'ing a bit, I found something which seems to be a bit similar to my problem at least: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=633851

Also there was an article mentioning that "all your gconf schemas have been unregistered for some reason" and suggesting this:

cd /usr/share/gconf/schemas/
sudo /usr/sbin/gconf-schemas --register *.schemas

However this was a quite old post so I doubt it's my case (and btw, it hasn't worked anyway ...)