Zone not mandatory in Guest checkout

[gswan]

Current AbanteCart version: 1.3.3
I've noticed that when a Guest checks out that the zone is not being checked to ensure it is there.
As a result the correct tax code is not applied and the order is wrong.
A test with other mandatory fields (country, postcode) throw the correct error message on the form.

We have 1 country, 7 states/zones.
Create order. Guest checkout. Fill in address and leave State/Zone empty.
It proceeds to the shipping/payment pages. Expected to throw an error for missing zone.

The localization messages for zone errors are all set (default).

Any clues would be helpful.
-Geoff

[Basara]

Hello.
Please update to the latest AbanteCart version