acpi - too hot, make world dies with various signals

Hello

I attempted to do make buildworld on my N610c laptop but it kept dying
with various signals
*** Signal 4
*** Signal 11

The fan does go off and on in response to high CPU activity but I am
guessing not enough and not soon enough.  I rebooted with acpi disabled
so that fan runs continuously (when there is AC power).  Buildworld is now
almost complete.

It would be nice if acpiconf had option to switch cooling on (permanently)
and off (well until acpi decided it was too hot).
(Hmm maybe if I had of used 'acpiconf -d' I wouldn't have had to reboot and
I could just disable thermal portion of acpi at boot. Wil that leave fan on
when no ac power??? hmm.)

Even better if acpi switched cooling on sooner.  I'll try to look at it myself
but that wont be till next weekend. But if anyone has patches or wants me
to get debug info I'd be happy to try.

thanks
--
tonym