Anyone else get this nasty bug with a recent build of 2.5 and Ubuntu x64?

I’m using Ubuntu 9.04 x64 and a recent build of 2.5 for linux x64. I think I found a bug when trying to modify baked particles my system completely freezes. Not just blender, the whole system. The only way for me to recover is to reboot. Does this happen to anyone else? Just save any work before trying to reproduce the bug.