Merging two source trees, identifying them by a matching @name

This was working well in xalan, albeit slow:

main stylesheet:
<xsl:variable name="doc" select="document('HostAdminFormDefinitions.xml')"/>

imported stylesheet:
<xsl:template match="my:form[@name=$doc//form/@name]">
	.. merge doms..
</xsl:template>


Switching over to Saxon gives the error:
"The match pattern in xsl:template may not contain references to variables"

Is there another way?


 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list