Index: includes/form.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/form.inc,v
retrieving revision 1.7
diff -u -r1.7 form.inc
--- includes/form.inc	26 Oct 2005 01:25:01 -0000	1.7
+++ includes/form.inc	29 Oct 2005 01:00:32 -0000
@@ -257,11 +257,18 @@
     $form[$key]['#tree'] = (isset($form[$key]['#tree'])) ? $form[$key]['#tree'] : $form['#tree'];
 
     if ($form[$key]['#tree']) {
-      //continue tree
-      $parents = (array) $form['#parents'];
-      array_push($parents, $key);
+      if (!$form['#tree']) {
+        // begin tree
+        $parents = array($key);
+      }
+      else {
+        //continue tree
+        $parents = (array) $form['#parents'];
+        array_push($parents, $key);
+      }
     }
     else {
+      // no tree
       $parents = array($key);
     }