--- nodehierarchy.module.orig	2014-04-21 11:25:00.835323323 -0500
+++ nodehierarchy.module	2014-09-03 13:49:53.094270571 -0500
@@ -1572,10 +1572,13 @@
  * Validate the parent node selector to make sure the parent is legal.
  */
 function nodehierarchy_parent_selector_validate($element, &$form_state) {
+ 
   $selection = @$element['#items'][$element['#value']];
-  if (is_array($selection) && !empty($selection['disabled'])) {
-    form_error($element, t('You have selected a parent node which cannot be a parent of this node type.'));
-
+  if (is_array($selection)) {
+    if (!empty($selection['disabled'])) {
+      form_error($element, t('You have selected a parent node which cannot be a parent of this node type.'));
+    }
+  
     if (!empty($selection['nid']) && !empty($form_state['values']['nid']) && in_array($form_state['values']['nid'], nodehierarchy_get_node_ancestor_nids($selection['nid']))) {
       form_error($element, t('The parent of this node can not be itself or any if its decendants.'));
     }