Check with your card processor. You can't help but break one or more rules unless you do so, as there are so many.
PCI compliance is a "big deal" at the moment, and getting your software approved could be difficult (if possible at all). It may be that your processor has a solution on the shelf that may help you.
Disclaimer: I don't know much about the front-end part of credit-card processing, but I do work work for a very large processor of credit card transactions.
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