XML feed - preprocessing - how to?

Hi,

using MashZone I'm pinging status of various components that return status in XML format. I was hoping to resolve a problem when component is down and no XML is returned with PREPROCESSING field  (XML data feed). Using XSLT I wanted to generate XML with status that says component is down but so far no luck. 

Outside of MashZone I can generate such a XML using this XSLT.

Can somebody help me out and give some example on this preprocessing feature?

Here is my example:

(xml)

<status>alive<status>

(xslt)

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

<xsl:output method="xml" indent="yes"/>

<xsl:template match="/">

<status>

  <xsl:if test="status">1</xsl:if>

  <xsl:if test="not(status)">0</xsl:if>

</status>

</xsl:template>

</xsl:stylesheet>