Function Key Problem



I'm running Mac OS 10.1 on an iBook G3, and I've been using it for about 2-3 years now without any problems or quirks whatsoever.

About 3 days ago, however, I found that my brightness, volume, num. lock, and eject keys refused to work unless the "FN" (function) key was pressed down as well. Also, if I pressed the any of the above mentioned keys without pressing the "FN" key, they acted as function keys (F1, F2, F3, etc) normally would.

In other words, if I wanted to eject a CD, I would normally just press the "eject" key without pressing anything else. Now, however, I have to press "fn"+"eject". If I don't press "fn" with it, it ends up acting like the "F12" key.

How can I fix this problem?

Thanks for your time.