function updateShipping(){
  if ( document.checkout.same_shipping.checked == false )  {
    document.checkout.x_ship_to_first_name.disabled = false;
    document.checkout.x_ship_to_last_name.disabled = false;
    document.checkout.x_ship_to_company.disabled = false;
    document.checkout.x_ship_to_address.disabled = false;
    document.checkout.x_ship_to_city.disabled = false;
    document.checkout.x_ship_to_state.disabled = false;
    document.checkout.x_ship_to_zip.disabled = false;
    document.checkout.x_ship_to_country.disabled = false;
  } 
  else {
    document.checkout.x_ship_to_first_name.disabled = true;
    document.checkout.x_ship_to_last_name.disabled = true;
    document.checkout.x_ship_to_company.disabled = true;
    document.checkout.x_ship_to_address.disabled = true;
    document.checkout.x_ship_to_city.disabled = true;
    document.checkout.x_ship_to_state.disabled = true;
    document.checkout.x_ship_to_zip.disabled = true;
    document.checkout.x_ship_to_country.disabled = true;
  }
}