mac-to-pc chats

[Kevin Justie]

On an all-Mac, iChat-using network, I've now added a PC with Pidgin.  Chatting between Mac and PC works perfectly -- as long as the PC initiates the chat.  If I try to initiate the chat from a Mac -- meaning the PC does not already have a chat conversation window open for the Mac -- the chat sent by the Mac never appears on the PC and on the Mac I get "The instant messaging connection failed."  Yet I can immediately chat from PC to Mac, and that works, and then I can chat back from Mac to PC.

Something I've missed in setup or configuration that's preventing initial  chats from showing up on the PC?

Thanks!

Kevin