$(function ()
  {
      $('input[name="service_change"]').click(function () {
          // Get selected type
          var checked_val = $('input[name="service_change"]:radio:checked').val();
          var full_classes = ['activity', 'subject', 'source_lang', 
                              'target_lang', 'payment_type', 'organisation',
                              'current_address', 'juridic_address',
                              'desired_date', 'delivery_method'];
          switch (checked_val)
          {
          case "S":
              for (var i = 0, j = full_classes.length; i < j; i++)
                  $("div." + full_classes[i]).hide();
              $('input[name="form_type"]').val('simple');
              break;
          case "F":
              for (var i = 0, j = full_classes.length; i < j; i++)
                  $("div." + full_classes[i]).show();
              $('input[name="form_type"]').val('full');
              break;
          }
      });
      var form_type = $('input[name="form_type"]').val();
      switch (form_type)
      {
      case "simple":
          $('#service_change_simple').attr('checked', 'checked');
          break;
      case "full":
          $('#service_change_full').attr('checked', 'checked');
          break;
      }
      $('input[name="service_change"]:checked').click();
  });