I've just made a change to MediaWiki so that it respects XFF headers for AOL
proxies. The change is live on Wikimedia right now. The logs seem to
indicate that AOL is not giving us XFF headers consistently, but hopefully
that's a problem we can sort out with them over the next few days.
I'd appreciate some reports from AOL users as to whether this is working.
http://meta.wikimedia.org/wiki/XFF_project
-- Tim Starling