I have had problems with all versions of 3.1 with the follow me feature shutting down a hunt group. ie. if user is in a hunt group and they turn on their follow me feature, it disables the entire hunt group.
Avaya is not saying anything about this problem but I have seen it on everyone that I have upgraded, when I go back to 3.059 it fixes the problem (not that it doesn't cause additional ones, but pick your poison).