datestyle in postgresql.conf, version 7.4

I want to have the date in french format for my postgres 7.4 database.
reading the documentation, three ways to get it.
1. set datestyle to 'postgres,european'; for each session, it works OK
2. old style export
PGDATESTYLE='Postgres,European';/usr/local/pgsql/bin/pg_ctl -D
/home/local/BasePostgres/ -l logfile -o -i start it works OK
3. datestyle="Postgres, European" in the postgresql.conf file, but
unfortunately it does nor work

what's wrong?

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Jean-Max Reymond email: jmreymond(at)free(dot)fr tel: 33 (0)6 16 94 25 11
http://jmreymond.free.fr/Etna2002