On 11/01/12 14:57, Reindl Harald wrote: > problem of the OP solved > that he can no longer act as MX properly is another story
...and the fact that openssh s_client gets around that block makes your answer completely useless, even though it may be "technically correct". The correct answer is that you cannot block telnet access to port 25 without also blocking incoming emails from other MTAs, and so you should not try. Peter