--- override_node_options.module	2009-04-11 17:57:08.000000000 +0600
+++ override_node_options.module	2009-09-23 17:18:48.000000000 +0600
@@ -254,7 +254,7 @@ function _override_node_options_apply_ke
               }
 
         // Node creation date override
-        if ($node->date !== $node->override_authored_on || !empty($node->override_authored_on)) {
+        if (($node->date !== $node->override_authored_on || !empty($node->override_authored_on)) && isset($node->override_authored_on)) {
          $node->date = $node->override_authored_on;
          $node->created = !empty($node->override_authored_on) ? strtotime($node->override_authored_on) : time();
         }