diff --git a/includes/common.inc b/includes/common.inc
index 2f5d6b1b2480690fb1624d0113d24933615de17b..e29627bac9f870b17a742443ddea96f695e17c97 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -1110,7 +1110,7 @@ function format_xml_elements($array) {
           $output .= drupal_attributes($value['attributes']);
         }
 
-        if ($value['value'] != '') {
+        if (isset($value['value']) && $value['value'] != '') {
           $output .= '>'. (is_array($value['value']) ? format_xml_elements($value['value']) : check_plain($value['value'])) .'</'. $value['key'] .">\n";
         }
         else {