Handling Credit Card processing- need solution

Hello SAP Gurus'

I need a solution in accepting credit card for payment against an invoice. My client here in the US has a CCC headquatered in Europe. They tell my client to input the credit card number and expiration date in the text field under customer open items and input request in assingment field. They in turn somehow process the credit card number and associate the payment with the invoice. They haven't provided a test of this yet. I don't believe it can happen. At any rate, I am NOT a proponent of having customer credit card info on the text field.

I understand there is a solution is changing the payment method to prompt the transaction thereby processing the credit card someone against the open receivable or balance on account. I am not sure how that part works.

Can anyone help me with the solution?

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