Hi Tim,
I have condensed Sun's
TableFTFEditDemo into what is possibly the smallest bit of code that I can use to discuss this - it creates a simple table where the third column will only allow integers between 100 and 999 to be entered.
See how you go with this and/or see how you go with Sun's
tutorials on the subject.
If in doubt, you can always come back and ask questions
Regards, Andrew