(OT, slightly) dealing with AOL spam reports?

[Mike Jackson]

A couple days ago, I set up AOL's "feedback loop" (though the loop part is a 
misnomer, since you can't actually respond to the messages) so I could 
monitor complaints against my employer's servers. Looking through the 
messages AOL says their members reported as spam, I noticed that none of 
them actually originated on my servers; they were all messages that were 
sent to addresses at the servers, then forwarded to AOL accounts, and since 
AOL records the IPs of all servers the message touched, I'm tainted by them.

So, how do you deal with this? My setup on the servers is like this:
* Sendmail
* Using Spamhaus SBL/XBL to deny listed servers at MTA level
* Most of the AOL forwarding is done via Sendmail's virtusertable
* Mail passed to SA via procmail on a per-user basis (not site-wide, yet, 
but that's in the plans)

The solutions I've already thought of and rejected:
* Invoking SA via milter and denying spam at the MTA level, but few 
customers would want spam denied outright (heck, I know I wouldn't). Of all 
these possible solutions, though, it's the only one that wouldn't leave my 
server's mark on the message.

* Setting up user accounts for the users with AOL forwards, filtering the 
mail through SA, then delivering it only if SA didn't mark it as spam, but 
that's a lot of users to set up.

* Doing the preceding with a single user account and redirecting the mail to 
the right addresses via procmail and/or formail, but that wouldn't scale 
well and would wind up being a mess.

* Invoking a policy of not forwarding to AOL accounts, but we're a web 
design/hosting firm with about 200 domains, and a handful of customers have 
AOL addresses, and that sort of policy wouldn't stand.

Any other workable suggestions? (And please, no suggestions that involve 
changing MTAs. It's not going to happen.)