Description:
------------
SimpleXML objects can be saved into a session file, but, they are not being extracted.


Reproduce code:
---------------
<?php	session_start();	// TEST1.PHP
$xml_string = <<< EOT
<GenQuoteDetails>
 <BaseFareAmt>26400</BaseFareAmt>
<TaxDataAry><TaxData><Country>US</Country><Amt>00019.80</Amt></TaxData></TaxDataAry>
</GenQuoteDetails>
EOT;
$xml_tree = simplexml_load_string( $xml_string );
$_SESSION['tree']	= $xml_tree;
echo"<pre>";print_r($xml_tree);echo"</pre>";
?>

<?php	session_start();	// TEST2.PHP
$xml_tree = $_SESSION['tree'];
echo"<pre>";print_r($xml_tree);echo"</pre>";
?>

Expected result:
----------------
SimpleXMLElement Object
(
    [BaseFareAmt] => 26400
    [TaxDataAry] => SimpleXMLElement Object
        (
            [TaxData] => SimpleXMLElement Object
                (
                    [Country] => US
                    [Amt] => 00019.80
                )

        )

)



Actual result:
--------------
SimpleXMLElement Object
(
)