diff --git a/includes/common.inc b/includes/common.inc
index ccadaee..0215b7c 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -224,7 +224,7 @@ function panelizer_add_revision_info_form_submit(&$form, &$form_state) {
   $entity = &$form_state['entity'];
   if (!empty($form_state['use revisions'])) {
     $entity->revision = $form_state['values']['revision'];
-    $entity->log = $form_state['values']['log'];
+    $entity->log = isset($form_state['values']['log']) ? $form_state['values']['log'] : "";
   }
 }