Do you have a SMP machine with SMP enabled in your OS? The unpredictable behavior of your freezes makes me think, that it could be related to multi-threading. OTOH arithmetic tests or such don't utilize threads and no events are being generated.
I am running a Cray X1 ( I wish ). I am on a redhat box on a bog standard single Athlon XP1700. I am stumped.
Harry
