Membership Provider How do I implement my CreateUser method and use it with CreateUser control

I am creating a Membership Provider for my web page and have a few questions. I have implemented most of the methods but have come across a problem. The method CreateUser takes various parameters but I want to create my own CreateUser method that takes more information like the users first and last name and other personal info. I could just create my own method but doesn't the asp.net CreateUser control call these override methods? How can I get the CreateUser controls to call my method and not the override methods? Or should I be doing this a different way? Thanks!
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