Please use PGP auth if could, though we describe header based auth here. Also please set up MTA properly e.g. to disable smtp interfaces as could as possible. It is a problem that PGP auth requires user's skill at some level. In the case of header based auth, you can create a mail magazine by using the asymmetirc member list. Consider asymmetric case of member list (list of persons who can post) and recipient list below. Firstly, remove $primary_member_map from $member_maps. Instead, define $ml_home_dir/members-mailmag who can post to $member_maps. member_maps = $ml_home_dir/members-mailmag The use of "subscribe" command is same as default one since "subscribe" command changes $primary_member_map not $member_maps. It is a little tricky but crafty use of $primary_XXX_map and $XX_maps enhances &fml8; configuration. In this case, when a new user is subscribed, the user address is added to both $ml_home_dir/members ($primary_member_map) and $ml_home_dir/recipinets ($primary_recipient_map). But $member_maps is defined as $ml_home_dir/members-mailmag. $ml_home_dir/members is not used. Hence, only the list of recipients is updated but the list of posters is NOT changed. Strictly speaking, this configuration is not enough safe. If somebody fakes From: address, he/she can post since fml checks only From: address. So, pgp auth is recommended. Another solution. primary_member_map = $tmp_dir/members-dummy and use $member_maps (member_maps = $ml_home_dir/members) for normal use. It has only poster's addresses. After 2004/06, &fml8; supports the queuing system. So the outgoing mail fails once, after the confirmation of content, you flush again to deliver if the content is ok. The queuing system support enables "queue once, dequeue after content confirmation". It avoids delivery of wrong content. The configuration is as follows. Specify irrelevant port at config.cf. smtp_servers = IRRELEVANT_PORT [Example] smtp_servers = 127.0.0.1:2025 This makes the delivery fail. The message is queued. Check the content. If the content is correct and delivery is ready, runs the following command by specifying the correct transport. % fml -o smtp_servers=TRANSPORT ML_NAME flushq [Example] % fml -o smtp_servers=127.0.0.1:25 ML_NAME flushq "flush" and "flushq" command are same.