You can do this in either a validation script or a formatting script, but to know exactly which you need to use depends on more than just changing the user input. Can you tell us a bit more about what exactly it is you want to do? Are you trying to do anything else with that modified number? Will it be used in a calculation? The more information you can give us, the easier it will be to help you.
And, please stop posting in all caps. It's rude and much harder to read than when you use proper capitalization.
Karl Heinz Kremer
PDF Acrobatics Without a Net
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