diff --git a/console.php b/console.php
index c331cf0..76a6a92 100644
--- a/console.php
+++ b/console.php
@@ -805,7 +805,7 @@ class console
     foreach ($historyArr as $line)
     {
       @list ($time, $command) = @explode (" ", $line, 2);
-      if ($time === null || $command === null)
+      if ($time === null || $command === null || ! ctype_digit ($time))
         continue;
       $this->history[$time] = $command;
     }