When using Adium, sometimes someone will initiate a conversation with me, and while I can see the stuff they write to me, they don't see my responses.
Closing the conversation window and starting a new conversation solves the problem.
I think, but am not sure, that this happens only when the other side is using Windows Messenger. (In other words, I don't think I ever see it for Yahoo! or AIM chats.)
Anybody else seeing this? Any advice for fixing it?