Postfix-to-mailman.py bug

The instructions for master.cf are incorrect. They claim

 argv=/var/lib/mailman/bin/postfix-to-mailman.py ${nexthop} ${user}

but it should be

 argv=/var/lib/mailman/bin/postfix-to-mailman.py ${nexthop} ${mailbox}

This is probably because postfix is configured out of the box to use '+' as the extension address separator and so treats addresses like 'list-join@domain' to be for a user called 'list-join'. Since I use '-' as the separator, postfix is reporting the user as only 'list'. Using ${mailbox} will preserve the extension and mail will be delivered correctly.

It's not clear this change will in anyway break functionality when postfix is configured with '+' as the separator. The only time the results would be different is if mail is going to something like 'list-join+ext@domain' and it's not clear why (how??) this would be the case.

Note: A list of macros you can pass into the argument can be found in postfix pipe manpage.