No mail sent

Hi all

New problem.

I installed postfix server on my centreon.

The follwing command : 

[centreon-engine@supervision2 ~]$ echo "Test" | mail -s "Test" louarn@mydomain works

bur I don’t receive any mails from centreon with /usr/bin/mail/

I don’t see any mail sent in /var/log/centegine.log.

Any idea ?

thanks