only in patch2:
unchanged:
--- modules/user.page_title.inc
+++ modules/user.page_title.inc
@@ -11,11 +11,12 @@
  * Implementation of hook_page_title_alter().
  */
 function user_page_title_alter(&$title) {
-  // If we're looking at either a user profile page or a users blog page, get the user title
-  if ($user = menu_get_object('user')) {
-    if (variable_get('page_title_user_showfield', 0) && ($user_title = page_title_load_title(arg(1), 'user'))) {
-      $title = $user_title;
-    }
+  // If we're looking at either a user profile page or a users blog page,
+  // get the user title.
+  if ( ($user = menu_get_object('user')) &&
+       variable_get('page_title_user_showfield', 0) &&
+       ($user_title = page_title_load_title($user->uid, 'user')) ) {
+    $title = $user_title;
   }
 }