Harddrive running too hot?

Hi,

I replaced the stock 20GB harddrive in my Thinkpad R40 with a 60GB
Fujitsu MHT2060AT.

I am running this configuration for over a year. Now I installed a
SMART tool (HDD health) which says that the temperature reading from
the drives sensor is 50 deg. celsius. This stays pretty much constant,
between 49 and 54 while idling.

Is this a sign that
1. the harddrive has (mechanical) problems, or
2. the Thinkpad isn't designed for a harddrive with higher dissipation,
or
3. is it normal for these drives to run so hot?

Is this too hot? And what can I do to cool it down (except for working
in the fridge)?

thanks,
-Robbe.

.