Mailing list + PGP/GPG support
Solution 1:
Pick whatever MTA and list manager you want. Install procmail, write quick procmail recipe to look for PGP signatures - allow message if the sig is found, deny if not found.
Pick whatever MTA and list manager you want. Install procmail, write quick procmail recipe to look for PGP signatures - allow message if the sig is found, deny if not found.