Description:
------------
Why it doesn't print anything?
It seems to work where i do a print_r( $obj )
but te access to $obj->Header and so on is impossible.

Thank you

Reproduce code:
---------------
<?php

$xml = <<<XML
<?xml version="1.0"?>
<env:Envelope xmlns:env="http://schemas.xmlsoap.org/soap/envelope/">
<env:Header>
<mm7:TransactionID env:mustUnderstand="1" xmlns:mm7="http://www.3gpp.org/ftp/Specs/archive/23_series/23.140/schema/REL-5-MM7-1-0">how-</mm7:TransactionID></env:Header>
<env:Body>
<mm7:SubmitRsp xmlns:mm7="http://www.3gpp.org/ftp/Specs/archive/23_series/23.140/schema/REL-5-MM7-1-0">
<MM7Version>5.3.0</MM7Version>
<Status>
<StatusCode>2007</StatusCode>
<StatusText>The MM7 request is incorrect</StatusText>
</Status>
<MessageID>101118737629315669</MessageID>
</mm7:SubmitRsp>
</env:Body>
</env:Envelope>
XML;

$obj = simplexml_load_string( $xml );
print_r( $obj->Header->TransactionId );

?>