I have setup: ìReject if name does not match addressî to check additional relay-based check on incoming mail connections.

Unfortunately, the DNS name of the connecting mail host and its IP addressí reverse-DNS entry is not the same for the major telephone based email supplier in Vienna, Austria. All mail from the host “aon.at” is rejected. This is a bit of a pain. The Telecom company won’t change. How can I set up my mail server to accept mail from this host and only this host?

Thanks….. 😕