Dear Zen-Cart Experts... I need some help of doing this modification on my shipping modules:

While the customers want to checkout: they have to choose that they are an "international costumer" or "domestic customer"

It looks like this site: Toko Serambi

Shipping based for international customers: country.
Shipping based for domestic customers: cities. (I mean: provinces>cities) The city list will be shown while they choose their province.

Thanks for the advice...