Anybody at ATT.net email services?

We're having trouble with ATT delaying our email. They are using a "grey-listing" technique to filter spam. Their mail servers give a "deferred" message and ask you to resend your email two hours later. The mail is allowed through on the retry. This filters out most spam, because most spam engines ignore return codes and will not retry. This is causing problems, because our mail servers are getting all clogged up with email to att.net customers and slowing down. Our difficulty has been in finding someone at AT&T to speak with about this. Can somebody from ATT.net help Netflix? Thanks Vish.