The element's value isn't HTML (or XHTML).

<?xml version="1.0"?>
<root>
<element>
&lt;p&gt;Rock &amp;amp; Roll&lt;/p&gt;
</element>
</root>
[download]

Rather, the element has XHTML children.

<?xml version="1.0"?>
<root xmlns:html="http://www.w3.org/1999/xhtml">
<element>
<html:p>Rock &amp; Roll</html:p>
</element>
</root>
[download]

Faced with the latter, you'd normally just ask for the XML of the node (->toString() or some such). However, that won't work with XML::Simple because its parser is too lossy to handle typical XHTML.