Who's name DOES show up when you do a reverse?
The address that's returned is: dsl027-160-095.atl1.dsl.speakeasy.net. In an experiment, I set the MX for imrics.net to point to it (after setting sendmail to accept mail for it), so that's what's in the MX record right now. Once upon a time, though, I used to point it at imrics.net. I left the dsl027* address in place because it seemed more logical to me. Either way seemed to be effective.
And - thanks if you can give me any insight (or help in connecting to warhead) - as you know, I don't claim any big expertise in this stuff... All I have is my own experience to go by - and I don't do this stuff professionally.