Yea, probably not as when you sign in, MSN Messenger 7 has to 'open your conversation window' to get you display picture for the toast and so it would cause alot of confusion and wouldn't really work as you wanted.
But I think what he meant was instead of it sending the message when the contact opens a window, it send it when they are 'typing a message'. So when it says at the bottom of the conversation window 'user is typing a message...' it would send it. This I think would be a good idea and plugin.
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