I notice 8.2 gave File Transfer fixes & 8.3 gave File Transfer Improvements, but 8.4 didn't mention anything about AIM file transfers..
I'm using 8.4 now and I can't send or recieve a single file on AIM.. File transfers work fine on the MSN protocol... [And also in Live Messenger, Google Talk (apps, not protocols)] ...so I don't think its any kind of firewall / router issue..
but I prefer Aim, since it supports resuming... but it doesn't work for me ! :(
PS: Plug-ins installed: CListModern, History++, TabSRMM