Database wont start anyway

["Fourat Zouari" <fourat(at)gmail(dot)com>]

Hello all,
My database wont start, here's the log :

tux2:~# /etc/init.d/postgresql-8.1 start
Starting PostgreSQL 8.1 database server: main* perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
        LANGUAGE = "fr_TN:fr_FR:fr:en_GB:en",
        LC_ALL = (unset),
        LANG = "fr_FR(at)euro"
    are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
Error: The server must be started under the locale fr_FR(at)euro which does not exist any more.
 failed!

what's the problem ?