[Wylug-discuss] Yahoo Mail sending mail incorrectly?

[Martyn Ranyard]

We have several companies with very similar setups, and one of them (possibly
all) has been having problems recieving mail from yahoo (I have implemented a
kludge, but thought I'd mention it so that others can a. be aware, and b.
possibly shed some light on the situation).

The DNS records are as follows for the company's domain :

A www ..... # IP of webserver (also backup mx)
A @ .... # IP of webserver (so http://domain.name works as well as www)
A halifax 213.xxx.xxx.xxx # ADSL IP with final destination mailserver running
MX (PRI 10) halifax.domain.name
MX (PRI 20) mx.bluefedora.co.uk # resolvable to the ip of web/backup mx server

This works really well (when I remember to add the domain names to
relay_domains in postfix on the backup mx server - grin).  Apart from yahoo,
which contacts the primary mail server (halifax), but with a very wierd RCPT
TO: command.  The email address it says it has email for is
user at hosting.bluefedora.co.uk - The only way I can think of it coming up with
this name is by forward and then reverse resolving mx.bluefedora.co.uk.  This
seems a very strange thing to do, but I cannot see any other reason for it.

Am I going mad, or is yahoo's mail system severely broken?

--
Martyn Ranyard
Synergistic Software Co. Ltd.