Allow registration hooks be required?

[Smokey-Rev]

For example, I have a hook installed on my forum that makes it so the user can enter their birthdate at registration, however as of right now there is no way to make that a required field at registration and they can just simply leave it blank if they wish to do so. Can a hook placement be put in so that the birthdate can be set to a required field so the new registratant must fill it out and it cannot be left blank?

Does this make sense? I'm not sure how I'd word it to make it more clear. :D Sorry....as you can tell I'm not a IPB modder. :P