Hello,
For some reason I will have my keywords added to the raw files.
The only free program I found to be able to do that is the ExifTool.
To simplify the adding the keywords I wrote a simple GUI as a frontend to the ExifTool.
The program is written I java, it´s simple and unpolished but it helps me adding keywords to my raw files.
I have tested it on Windows 7 and Debian 6.0 but only with jpg and Canons raw files CR2.
Feel free to test the program but don't forget to back up your images!
/Leif
Some screen shots.