Description:
------------
Base path cannot be changed by setting the parameter xslt_base_dir in the xslt processor. This bug was also reported here : http://bugs.php.net/bug.php?id=43454&edit=3

Reproduce code:
---------------
<?php
// First, load a XSL stylesheet
$xslDom = DomDocument::loadXML('<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"><xsl:include href="foo"/></xsl:stylesheet>');

// Then initialize the XSLTProcessor
$xsltProcessor = new xsltprocessor();

// Set the xslt_base_dir
$xsltProcessor->setParameter('','xslt_base_dir','base');


// Import the stylesheet in the processor
$xsltProcessor->importStylesheet($xslDom);
?>

Expected result:
----------------
This program should raise the following warning : Failed to load external entity ".../base/foo"

Actual result:
--------------
The program raises the warning : Failed to load external entity ".../foo"