Index: node_widget.form.inc
===================================================================
--- node_widget.form.inc	(revision 35947)
+++ node_widget.form.inc	(working copy)
@@ -157,10 +157,12 @@
  */
 function node_widget_get_fields(&$form) {
   $fields = array();
-  foreach (content_fields() as $field_name => $field) {
-    if ($form['type']['#value'] == $field['type_name'] && $field['type'] == 'nodereference' && $field['widget']['type'] == 'node_widget_node_form') {
-      $fields[$field_name] = $field;
+  if (isset($form['type'])) {
+    foreach (content_fields() as $field_name => $field) {
+      if ($form['type']['#value'] == $field['type_name'] && $field['type'] == 'nodereference' && $field['widget']['type'] == 'node_widget_node_form') {
+        $fields[$field_name] = $field;
+      }
     }
   }
   return $fields;
-}
\ No newline at end of file
+}