First off: Score!
Secondly: I agree with Llyren. They're not replying sounds rather suspicious, you just might be able to help bust on of those "mule" accounts that are so hard for the anti-Gold task-force team to catch.
Lastly: Do you find yourself missing any items? Are you sure you have a secure password, no funky access warning emails, etc? Sometimes, gold farmers will hijack an account and use if for no other reason than a transfer mule: they'll email stuff to it, log in, collect the stuff, delete the email, and transfer it to another mule. No one is the wiser, and it messes with GMs trying to trace transfer trails, because they run into a "legit" player who has no idea what is going on.
That practice is also applied to email accounts, too, for purposes of spamming, fraud, etc, so its nothing new to gaming.
Just curious.