Country/State Dropdown in CakePHP

How do i deal with dependent combo boxes in the views with the form helper. For example:

Country Select Box (Choosing a country shall filter out the states of the selected country)
States Select Box

This should happen with the help of Javascript / Jquery etc. I came across an example for the same with Cake's core AJAX helper but it would be very nice if someone can help with a Javascript example.

Thanks