Oopps.. No there seems to be another issue with mailman..
I have subscribed some test mail accounts on my test-mailing list - 2 of the mail accounts are external (gmail and yahoo), and one is from my domain (user@mydomain.net).
I can send to the test-mailing list with no problems from the
user@mydomain.net account, and the gmail and yahoo accounts receive the message, but when I try to send a message from any external account like gmail or yahoo the message is never to be delivered.
Still looking in the logs - nothing. Started tcpdump on both interfaces - on the gateway and webserver just to see if there is something blocked - nothing..
I'm lost.. Any advice?