vQmod throws the following error when parsing an XML file:
Warning: strpos(): Empty needle in /home/public_html/vqmod/vqmod.php on line 455
Here's the XML itself:
<operation>
<search position="before">
<?php echo $footer; ?>
</search>
<add><![CDATA[
<?php phpinfo(); ?>
]]></add>
</operation>
XML file looks ok, all paths are correct.
Didn't find anything relevant on the internet so posting my solution here (see below).