diff --git a/js/misc/_vertical-tabs.js b/js/misc/_vertical-tabs.js
index 69d188f..f234d4b 100644
--- a/js/misc/_vertical-tabs.js
+++ b/js/misc/_vertical-tabs.js
@@ -118,7 +118,7 @@ Drupal.verticalTab.prototype = {
           tab.item.removeClass('selected');
         })
         .end()
-        .addClass('fade in')
+        .addClass('fade in active')
         .siblings(':hidden.vertical-tabs-active-tab')
         .val(this.fieldset.attr('id'));
     this.fieldset.data('verticalTab').item.find('a').tab('show');