How to make an XMLDocument as a parameter in a XSLT transformation ?

I'm trying to make an XML available as a parameter in a XSLT
transformation (use case like mixing up business data to be transformed
to a HTML GUI with say language dependent text data for labels' texts
or something).

I'm quite new to the Mozilla API for XML but I know a thing or two
about MSMXL where i used this approach that has often prooved simple
and useful.

Is this possible some way (a way in which i should be able to code the
xsl only once for BOTH, msxml and Mozilla)? Or are there other
approaches allowing similar usage?

code would look something like:

--js-------
var httprequest = new XMLHttpRequest();
httprequest.open("GET", "data2.xml", this.async);
httprequest.send(null);
var dom2 = httprequest.responseXML;

var xsltproc = new XSLTProcessor()
xsltproc.clearParameters();
xsltproc.setParameter(null, "dom2", xml2);

var dom = this.xsltproc.transformToDocument(xml.dom);
var serializer = new XMLSerializer();

--xsl-------
<xsl:stylesheet version="1.1"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:param name="domext"/>

 <xsl:template match="/*">
  <ul>
   <xsl:apply-templates />
  </ul>
 </xsl:template>

 <xsl:template match="container">
  <li><xsl:value-of select="$domext//text[@id=current()/@id]"/></li>
 </xsl:template>

 <xsl:template match="composite">
  <ul>
   <xsl:apply-templates />
  </ul>
 </xsl:template>

</xsl:stylesheet>

--xml-------
<?xml version="1.0" ?>
<labels>
	<text id="c0">text c0</text>
	<text id="c1">text c1</text>
	<text id="c2">text c2</text>
	<text id="c3">text c3</text>
</labels>

Thanks in advance for any help!