i think it has been blacklisted... i've had some spamming problems in the past which people misusing the server....
its not just newsletters coming back but also automated messages from the forums to members
The original message was received at Tue, 6 Feb 2007 01:36:00 GMT
from archiseek@localhost
----- The following addresses had transient non-fatal errors -----
john@xxxxxxx.ie
----- Transcript of session follows -----
john@xxxxxxx.ie... Deferred: Connection refused by av.blacknight.ie.
Warning: message still undelivered after 4 hours
Will keep trying until message is 5 days old