mozilla freezes FC2 machine(?)

[Anne & Lynn Wheeler]

for the past 3-4 weeks or so ... i've gotten very sporadic
machine freezes (nothing is running and have to power
cycle) when mozilla is loading some website. 

Happens with mozilla 1.7 thru 1.8a thru current nightly 
builds. happens whether new website is being loaded into 
visable tab or background tab. mozilla's is running with 
java, javascript, popups, etc all disabled.

happens up thru smp kernel 2.6.6-1.435.2.3

machine is new dell 8100 with threading enabled and a 
SMP kernel. 

did not happen with earlier fc2 (smp) kernels prior to 4
weeks or so ago. doesn't seem to be mozilla since was using 
some of the same mozillas prior to the freezing appearing.
by the time I noticed it happening, I had deleted earlier
kernels where the freezes weren't happening.

the mozilla web page load issue is the only situation
that i've observed it happening.