for example, a zip code field only contains digits and up to 5 digits
I hope that's not a compulsory field - don't forget about those of us outside the USA who have different systems for our zip codes, for example in the UK a valid post code is 1* or 2 letters, followed by 1 or two digits, a space, a digit and 2 more letters. If I were trying to register for your site and you made me enter a zip code your way, I'd just have to make something up ;)

* Normally 2 letters, but London just had to be different

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My cow-orkers were talking in punctuation the other day. What disturbed me most was that I understood it.

In reply to Re: Form Checking and Tainting by Nevtlathiel
in thread Form Checking and Tainting by Anonymous Monk

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