MAGENTO Force customer to fulfill the address form again

I created a new attribute to the address form and it is working fine, my problem is with older customers. How can I make force them to have to edit their address?

WHen they go to the checkout page, they choose th开发者_如何学Goe old address without knowing about the new attribute, and it is really important for us that they fill it properly

Well,

What I did to accomplish this was editing the billing.phtml directly under mage/sales/checkout/ and add some code to directly check if the new attribute exists for the address

using complete sql like:

SELECT * FROM customer_address_entity_varchar WHERE attribute_id = my_new_attribute_id AND entity_id = my_address_id

thanks,
Jonathan