Further to on-list discussions another sysadmin friend of mine suggested
that the fact that the A record for my MX doesn't match the PTR record
might be an issue but I feel it is a red herring.
I'm pretty sure multiple PTR records is not allowed (or at least
discouraged) anyway, which means I would need to start using the real
name of my machine for the MX record instead of the one I am using.
This isn't that much of a problem really, just means I don't have a nice
'mail.*' MX entry.
Thoughts?
n