Name requirements

[NathanLedet]

I'm wondering if there's a mod that could be made or is already made that requires 2 fields to make a user name.

I'm working on a forum right now and the owner insists on users registering with their first AND last name. What i'm thinking is when someone registers, instead of "username", they see "First Name" and then there is an additional box below it that says "Last Name"

So, when they register, they fill out "John" in the first box, "Doe" in the second box, and their username ends up being "John Doe"