A Thinkpad or an Airline?

[EastCoastCoder]

I have a ThinkPad R52, works great, except:

The fan always goes on, even for no apparent reason, and sounds like an airplain taking off!

Okay, that's a bit of an exaggeration, but, even when the CPU usage is low, for some reason, the fan often goes on, and stays on. It seems to be a bug, because when I "reset" it - by taking out the power cord, and switching it to battery - the fan goes off after 30 seconds. (And, vice versa - to "reset" it when it is on battery, I need to plug it in). I found this really annoying! Can anyone help me?

(And yes, I just upgraded to the latest Embedded Controller & Thermal Software, from IBM...)[/b]