I am seeing the same, but do not know when it happened. A few days ago (probably soon after being able to run the server) I noticed a stonebreaker flying around the npcroom with his arms spread out, flickering. No idea if it started after attacking him. They are still doing this when I start the npcclient now. I can see one two or three at the same time. They are from the Tribe, different members do this once they start moving. In the console I see only tribemember1 mentioned. After they 'walk' back to the group, they look normal.
It sounds a bit like this
http://www.hydlaa.com/bugtracker/bug.php?op=show&bugid=1687&pos=1I looked at it a bit further: when I target a moving tribemember and ask for it's position with /pos repeatedly, it mostly gives a sensible (moving) position, but sometimes I get something like:
Tribe1Member2's current position is -94010208.00,0.00,59530700.00 angle 302 in sector: NPCroom, region: npcroom
Asking /pos very quickly then crashed the server, but that is another issue
