Voila exactement!
benoit@arthux ~/mail $ locale
LANG=fr_BE@Euro
LC_CTYPE="fr_BE@euro"
LC_NUMERIC="fr_BE@euro"
LC_TIME="fr_BE@euro"
LC_COLLATE="fr_BE@euro"
LC_MONETARY="fr_BE@euro"
LC_MESSAGES="fr_BE@euro"
LC_PAPER="fr_BE@euro"
LC_NAME="fr_BE@euro"
LC_ADDRESS="fr_BE@euro"
LC_TELEPHONE="fr_BE@euro"
LC_MEASUREMENT="fr_BE@euro"
LC_IDENTIFICATION="fr_BE@euro"
LC_ALL=fr_BE@euro