--- taxonomy.orig.inc	2008-03-29 03:05:44.000000000 +0100
+++ taxonomy.inc	2008-06-20 10:38:17.296875000 +0200
@@ -174,10 +174,9 @@
       '#default_value' => variable_get("hierarchical_select_dropbox_limit_{$vid}", 0),
     );
 
-    $form['#submit']['taxonomy_form_vocabulary_submit'] = array(); // Make sure the original submit handler is still called.
     $form['#validate']['hierarchical_select_taxonomy_form_vocabulary_validate'] = array();
     $form['#submit']['hierarchical_select_taxonomy_form_vocabulary_submit'] = array();
-    $form += $third_part;
+    $form = array_merge_recursive($form, $third_part);
   }
 
   // Change the exposed filters of Views. Only affects hierarchical vocabulary