Home Linux box can't send to AOL this week

[Rich Braun]

Have any of you gotten this, as a result of an apparent policy change
at AOL in the past few days?  I have a Linux email server running
sendmail 8.12.9, connected to Comcast aka ATT-BI aka MediaOne, formerly
Continental Cable:

<<< 550-The IP address you are using to connect to AOL is either open to
<<< 550-the free relaying of e-mail, is serving as an open proxy, or is a
<<< 550-dynamic (residential) IP address.  AOL cannot accept further e-mail
<<< 550-transactions from your server until either your server is closed to
<<< 550-free relaying/proxy, or your ISP removes your IP address from their
<<< 550-list of dynamic IP addresses.  For additional information,
<<< 550-please visit http://postmaster.info.aol.com.
<<< 550 Goodbye

I am apparently now classified as a "dynamic (residential) IP".  This
message comes back whenever I try to email any of my friends @aol.  What
should I do about this?  I don't even know the names of the relay servers
at Comcast and I doubt they're configured correctly.  But I figure some
of y'all must have run into this, or are about to.

-rich