I've exactly the same problem with my compaq armada E500 laptop
. I do have a fan /proc/fan entry, but I don't now if I should do something with that...
I've found something which could be useful. Linuxted, plz try it out as I'm at my work and can't test it right now. On this
page there is a package called acpi_event_scripts-08192003.tar.gz. Just install it with the provided readme and let us know if it works or not.