Description:
------------
See the attached test script.

If you use 
$file->a[0] = &$log; 
instead of 
$file->a[0] = $log;
everything works fine and you can unserialize the string. But the serialization with the lowercase "r" throws an error when during unserialization.

Reproduce code:
---------------
--TEST--
Bug # (Wrong serialization of objects with recursive references)
--FILE--
<?php

$rep = new stdClass;
$file = new stdClass;
$log = new stdClass;

$file->rep = &$rep;
$log->file = &$file;
$file->a[0] = $log;

echo serialize($file);

?>
--EXPECT--
O:8:"stdClass":2:{s:3:"rep";O:8:"stdClass":0:{}s:1:"a";a:1:{i:0;O:8:"stdClass":1:{s:4:"file";O:8:"stdClass":2:{s:3:"rep";R:2;s:1:"a";a:1:{i:0;R:4;}}}}}