Add mydestination to prevent hostname == domain situations

data/conf/postfix/main.cf

@@ -90,3 +90,4 @@ virtual_uid_maps = static:5000
 smtpd_milters = inet:rmilter:9900
 non_smtpd_milters = inet:rmilter:9900
 milter_mail_macros = i {mail_addr} {client_addr} {client_name} {auth_authen}
+mydestination = localhost.localdomain, localhost