Presence Error

What could cause the presence error that is shown in the attached file? These were taken from a message audit log today. We are running OpenFire 3.6.2. These same messages are repeated, i.e. it appears to be in a loop. It not obvous from the messages who the user is.
PresenceError.txt (1536 Bytes)

This was apparently caused by the Exodus 0.9.1 client that of few our our uers were trying. Disconnecting those clients cleared the problem.