More AOL spam reporting woes

My DH-hosted site ( routinely sends out registration confirmations, as well as phpBB-related notices (PM notices, watched threads etc).

As is seemingly a common problem, one of our members on AOL has reported such a mail as spam, and consquently AOL has blocked the mailserver, meaning that no AOL-based users are receiving alerts. The message on the bounced mails reads like:

host[] said: 421-:

The AOL postmaster site there suggests that the only way to get of the blocked list is for the ISP to clear it with AOL.

So what does DH do in these cases? Is there anything more I can do to get back in AOL’s good books?