fix manually modified serialized string

fix.php

<?php
$initialData = file_get_contents("./old.ser");
$data = preg_replace('!s:(\d+):"(.*?)";!e', "'s:'.strlen('$2').':\"$2\";'", $initialData);
$fp = fopen ("./new.ser", "w");
fwrite($fp, $data);
fclose($fp);