Description:
------------
I'm trying to store an SplQueue object in the session, on page reload the SplQueue object is still there, but it has no data. This happens on Windows XP (Apache 2.0.58), but also on Fedora 8 (apache 2.2), and a Debian build running apache 2.2.

Reproduce code:
---------------
<?php
	$q = new SplQueue();
	$q->enqueue('something');
	$q->enqueue('over there');
	session_start();
	$_SESSION['q'] = $q;
?>
on the second page
<?php
	session_start();
	$q = $_SESSION['q'];
	print '<pre>';
	print_r($q);

Expected result:
----------------
SplQueue Object
(
    [flags:SplDoublyLinkedList:private] => 4
    [dllist:SplDoublyLinkedList:private] => Array
        (
            [0] => something
            [1] => over there
        )

)


Actual result:
--------------
SplQueue Object
(
    [flags:SplDoublyLinkedList:private] => 4
    [dllist:SplDoublyLinkedList:private] => Array
        (
        )

)