All e-mail sent from a yahoo.com server to my domain fails to be correctly received. The difference between yahoo.com and other domains is that they open with HELO rather than EHLO and therefore attempt to send the data in one part rather than in chunks (as I understand it).
Looking at the wikipedia example communication it seems that we are conforming to the protocol our side. When we expect data to arrive with us however the yahoo server fails to reply leading to a timeout.
2010-10-27T09:17:15.52...-,,Local 2010-10-27T09:17:18.11...+,, 2010-10-27T09:17:18.11...*,SMTPSubmit SMTPAcceptAnySender SMTPAcceptAuthoritativeDomainSender AcceptRoutingHeaders,Set Session Permissions 2010-10-27T09:17:18.11...>,"220 remote.ourserver.co.uk Microsoft ESMTP MAIL Service ready at Wed, 27 Oct 2010 10:17:17 +0100", 2010-10-27T09:17:18.13...<,HELO omp1009.mail.ukl.yahoo.com, 2010-10-27T09:17:18.13...>,250 remote.ourserver.co.uk Hello [xxx.xxx.xxx.xxx], 2010-10-27T09:17:18.14...<,MAIL FROM:<email@example.com>, 2010-10-27T09:17:18.14...*,08CD4019188CB09A;2010-10-27T09:17:18.111Z;1,receiving message 2010-10-27T09:17:18.14...>,250 2.1.0 Sender OK, 2010-10-27T09:17:18.16...<,RCPT TO:<firstname.lastname@example.org>, 2010-10-27T09:17:18.16...>,250 2.1.5 Recipient OK, 2010-10-27T09:17:18.17...,<,DATA, 2010-10-27T09:17:18.17...,>,354 Start mail input; end with <CRLF>.<CRLF>, 2010-10-27T09:19:08.19...
I am stumped as to what to try, I attempted to manually telnet and send an e-mail but I get rejected as I don't have a valid server to send from (I get refused as potential junk).
I have access to the logs of the box but not easy access to the config. Any advice would be greatly appreciated.