[Mailman-Users] IP blacklisted by at&t

[Jason Fayre]

Hi,
This may not be strictly on-topic for this list, but I'm getting 
extremely frustrated and am  hoping someone can give me some ideas.
We moved our mailman server to a VPS with a new IP address.  After the 
move, our IP has been blacklisted by AT&T.  We had some DNS trouble 
initially, and this may be why.
I've submitted the form that at&t tells you to in order to get your IP 
removed from the blacklist.  I then get a response back saying that the 
IP is not blacklisted.  However, I've got recent bounce messages saying 
we are.  If I try and telnet to at&t's mail servers from the mailman 
server, I get rejected because of a blacklisted Ip.  The IP they are 
saying is blacklisted is the same one I submitted on there web form.
Does anyone have any strategies in dealing with at&t?  I would love... 
god forbid... to actually talk to someone in their postmaster team about 
this.
We host around 200 mailing lists for the National Federation of the 
Blind.  Some of the lists are fairly high traffic.  We are not sending 
out spam.
Any help or suggestions would be apreciated.