xslt chuck question

Hi all

I'm getting the following error as I'm trying to create a chunking 
customization layer:

<<runtime error: file 
/net/pyxis/oxygen/oxygen-6.2/frameworks/docbook/xsl/html/chunk-code.xsl 
line 512 element choose
unregistered variable rootid
xmlXPathCompiledEval: evaluation failed>>

Here's the associated code

   <xsl:if test="$collect.xref.targets != 'only'">
        <xsl:apply-templates select="key('id',$rootid)"
                     mode="process.root"/>
        <xsl:if test="$tex.math.in.alt != ''">
          <xsl:apply-templates select="key('id',$rootid)"
                       mode="collect.tex.math"/>
        </xsl:if>
        <xsl:if test="$generate.manifest != 0">
          <xsl:call-template name="generate.manifest">
            <xsl:with-param name="node" select="key('id',$rootid)"/>
          </xsl:call-template>
        </xsl:if> (this is line 512)
          </xsl:if>

Here's my customization layer code:

<?xml version='1.0'?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
version="1.0">
<!-- <xsl:import 
href="file:/net/pyxis/oxygen/current/frameworks/docbook/xsl/html/chunk.xsl"/> 
-->
<!-- <xsl:import href="file:xsl/pxdoc-customization-layer-common.xsl"/> 
--> 

  <xsl:param name="chunk.first.sections" select="'1'"/>
  <xsl:param name="chunk.section.depth" select="'3'"/>
  <xsl:param name="use.id.as.filename" select="'1'"/>
  <xsl:param name="root.filename" select="'pxdoc'"/>
  <xsl:param name="html.stylesheet" select="'css/common.css'"/>
  <xsl:param name="chapter.autolabel" select="'0'"/>
  <xsl:param name="suppress.navigation" select="1"/>
  <xsl:param name="generate.legalnotice.link" select="1"/>

</xsl:stylesheet>

And lastly, here's the code from the "mychunk.xsl" file

<xsl:import 
href="/nhome/karib/work/doc/html/xsl/pxdoc-customization-layer-html.xsl"/>
<xsl:import href="chunk-common.xsl"/>
<xsl:include href="manifest.xsl"/>
<xsl:include href="chunk-code.xsl"/>

Any clue as to what the error is that I'm getting?

thanks!


-- 
Kari Bourgeois
Technical Writer
Pyxis Technology
512-637-0519