Beta 3 Crash with machdep.hlt_logical_cpus

I am running on a Dual 1.8 Ghz Xeon box and I have hyperthreading turned
on in the BIOS such that it appears that I have 4 processors.  I am not
physically at the machine right now but wanted to report a problem I had
today.  I changed machdep.hlt_logical_cpus from 0 to 1 while running and
the system completely froze up.  I don't know what error occurred as I
wasn't at the machine and have rebooted since then.  I do know that using
5.2 I was able to do this and the sytstem would move all the processes to
the correct CPU's.  Not sure if anyone else has seen this.

Rusty Nejdl