Occasionally empathy will send messages I've typed to one contact to a different contact entirely. The conversation will continue in the window of the person I meant to type to, but I'll actually be talking to a different contact entirely. This has only happened to me with msn contacts (using telepathy-butterfly), and I have no reliable way of reproducing this bug. I originally reported this at the Gnome bugzilla, but it was determined it is most likely a telepathy-butterfly bug - see http://bugzilla.gnome.org/show_bug.cgi?id=568640 .
It would be good if you could use get master version of butterfly: git clone git://git.collabora.co.uk/git/telepathy-butterfly.git and then always run it from a console: BUTTERFLY_PERSIST=1 ./telepathy-butterfly so next time you'll observe the bug, you'll have log in the console.
You could even use the newly supported BUTTERFLY_LOGFILE environment variable to catch the logs in a file instead.
This bug hasn't reoccured at all when using the git master version - can probably assume this bug no longer occurs.
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