Index: moodle/lib/weblib.php
--- moodle/lib/weblib.php Base (1.970.2.148)
+++ moodle/lib/weblib.php Locally Modified (Based On 1.970.2.148)
@@ -1007,8 +1007,7 @@
     }
     if (!empty($options)) {
         foreach ($options as $section => $values) {
-
-            $output .= '   <optgroup label="'. s(format_string($section)) .'">'."\n";
+            $output .= '   <optgroup label="'. format_string($section) .'">'."\n";
             foreach ($values as $value => $label) {
                 $output .= '   <option value="'. format_string($value) .'"';
                 if ((string)$value == (string)$selected) {