dovecot - Nov 2010 - dovecot transport with postfix and recipient restrictions.

I'm using dovecot deliver with my postfix smtp.
In postfix configuration I have:


smtpd_recipient_restrictions check_recipient_access
hash:/etc/postfix/maps/recipient_checks

and in recipient_checks I have:

mail at example.com REJECT.
It doesn't work.
Perhaps the recipient restriction has to be put in dovecot side?
How can I do this.