Issue with Country and States fields

Hello
We are dealing with an issue related to Country and State (Regions) field.

Here is our question.

When a user registers on our site, he has to fill the Country (Mandatory) and the State (also mandatory) fields.

The problem is that after selecting the Country, the States field is not directly updated to show the States options for this country.

This does not allow registration to go on because as i mentioned before The State field is Mandatory.

I do attach a screenshot, so that you can understand our issue better.


NOTE:
On profile edit... when you change country, you have to save first so that the states of this country appear.

Please Advise...

Thank you.