try.js

gistfile1.txt

$(document).ready(function(){



  $('select[name="country"]').change(changeProvince());
  

  var changeProvince = function(){
    var country = this.value;
    console.log(country);
    $('select[name="province"] option').hide();
    $('select[name="province"] option[value^=' + country + ']').show(); 
    //refresh select options
    try{
    MSDropDown.init();
    }catch(e){
      //forget
    }
  };
  
  
});