diff --git a/database/updates.inc b/database/updates.inc
index 5cb099bf9b26548e2074754609d97f3a0e2836cc..04bd928b712d15487fb4e59c35a907fea3f5c5e1 100644
--- a/database/updates.inc
+++ b/database/updates.inc
@@ -1335,7 +1335,7 @@ function system_update_164() {
 }
 
 function system_update_165() {
-  $cron_last = max(variable_get('drupal_cron_last'), variable_get('ping_cron_last'));
+  $cron_last = max(variable_get('drupal_cron_last', 0), variable_get('ping_cron_last', 0));
   variable_set('cron_last', $cron_last);
   variable_del('drupal_cron_last');
   variable_del('ping_cron_last');