I discovered today that if I am standing outside a log cabin (having just exited but not yet walked anywhere), that when another player exits the same log cabin, we both become stuck. I assume it's because we both appear inside each others collision area. I had my friend log out to fix this problem, but you can see how it might be a problem. I don't know if the same thing can happen on the inside of a log cabin, as I did not test this.
A sensible solution to this might be causing one of the players to be shunted. Anyway, I hope this helps.