Are you sure it is running cool? If you're on Windows, try a program like
SpeedFan to check the temperature of any sensors your computer may have. You may be able to up the fan speeds as well, depending on compatibility with your hardware.
If your laptop remains cool, it's odd that you say the RAM is getting hot. If the RAM is in a totally different area than other areas of the computer with a fan, there probably isn't too much you can do. But considering this is probably a new issue to an old computer, I'm guessing something changed.
At this point, it's probably not a bad idea to open the covers and clean out any gunk you can. There may be obstructions in the fan that are causing poor airflow, or a general buildup of dust. Considering the laptop came out in 2003, you could have up to 6 years of buildup inside of the case. I'd really consider cleaning it, even if you weren't having problems.
If cleaning doesn't fix the problem, and the fan is still working, you may want buy a laptop stand, and/or make sure you are using it on a flat surface that provides good airflow. I know how the older Dell laptops vent all of the air either out the bottom, or in through the bottom. Horrible, if you're using it on a couch or something else that doesn't provide good airflow.