I'm also affected; a Thinkpad R61i model 7650-range, preinstalled Ubuntu 8.04, currently running kernel 2.6.24-23, as had boot issues with -24.
(probably got the most recent ACPI patches for Hardy)
Fan running slowly - was cooking my laptop more.
I have had to buy a laptop cooler so I can safely use it.
PLEASE fix it for us on Hardy as well!