Description:
------------
simplexml_load_string not producing the expected results


Reproduce code:
---------------
  $xml = <<<XML
<?xml version="1.0" encoding="utf-8"?>
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <soapenv:Body>
        <ns1:createBanResponse soapenv:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" xmlns:ns1="http://ws.interfaces.sessions.APILink.amdocs">
            <createBanReturn href="#id0" />
        </ns1:createBanResponse>
        <multiRef id="id0" soapenc:root="0" soapenv:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" xsi:type="ns2:OutCreateBanInfo" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:ns2="http://io.datainfo.APILink.amdocs">
            <ban xsi:type="xsd:int">688666259</ban>
        </multiRef>
    </soapenv:Body>
</soapenv:Envelope>
XML;
    $root = simplexml_load_string($xml);
    var_dump($root); //EMPTY

$result = $root->xpath("ban");//EMPTY

print_r($result);//EMPTY

Expected result:
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I expected some data from the xml. For example xpath should return 
688666259.  I use simplexml_load_string many time and never have 
problems. I never used it with an xml with so many attributes.

Actual result:
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Array ( ) object(SimpleXMLElement)#1 (0) { }