1341 smp (and all other recent smp) freezeup @ login prompt

[Jonathan Deitch]

On a FC4T3 system, with latest yum updates ...

Dual xeon system running on an Intel server motherboard, getting a 
freeze after the boot process completes ... login appears, cursor 
blinks, but keyboard/mouse are unresponsive, as well as network (system 
appears hung) - can only reset to fix.

Booting the UP kernel system works flawlessly ...

Checking in logs, there's *no* logging at all for the smp boot - it's as 
if it never happened.

any ideas?  I'm flat-out stumped ...

- Jonathan