How do I setup Shipping Zones (not per country)

Sorry if I have missed something, its been a long day...

I am confused by shipping Zones. In Admin I create Countries AND Zones, and the zones are parts of a country. Then I go to Shipping -> Zone Rates, but it seems Zone in this context is referring to Country. It asks to enter Country codes, not Zone codes. So am I right in saying this is not actually a Zone shipping module, but a Country shipping module?

If I enter my Zone codes in here it doesn't work, checkout says there are no shipping rates for my country.

So where can I setup the different Zone Rates (areas within my country)?

Thanks

I found this add on
http://www.zen-cart.com/index.php?main_page=product_contrib_info&cPath=40_51&products_id=697

It seems this does the trick. I had to setup the Zone Definitions first, assign the Zones to the Zone Definitions. Then in this module I can choose a flat rate to assign for each Zone Definition.