date in european style

Hello:

I'm using postgresql v7.0.2, from RedHat 7.0 installation. How can I
configure it to use dates in european format? I used to put -o-e in the
execution of postmaster in /etc/rc.d/rc.init/postgresql, but now they
use a different program to start (pg_ctl):

su -l postgres -c "/usr/bin/pg_ctl -D $PGDATA -p /usr/bin/postmaster
start >/dev/null 2>&1" < /dev/null

Thanks in advance

-- 
Salvador Mainé