Comment 9 for bug 1022593

workaround about post #3 above:

initial /etc/environment was:
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games"

adding a second line :
 LC_ALL="fr_FR.utf8"

solve this post #3 problem , but not the main issue : "apply to whole system" endless looping into the language gui.