I have a need for a security script that will block multiple attempts by fraudulent credit cards by adding their IP address to a banned list. Should be able to detect based on X number of attempts in Y number of minutes/seconds. We have been getting hammered by one particular hacker who has attempted as many as 2,000 credit card transactions in one day using approximately 50 different IP addresses. We need something bulletproof and quickly. Must be able to co-exist with a shopping cart system.