Martin this is Great! I never thought it can be done this short way. I was
doing a 3 level deep <choose> but still not working. There was only one
complain from the compiler that cn is declared as string:
> 
>   <xsl:template
match="node()">
>     <xsl:param name="cn"/>
>     <xsl:if
test="descendant-or-self::node() intersect $cn">

So i changed it to
<xsl:param name="cn" select="/.."/>
and now it is working as a charm.
I am
really thankful to get an answer this quickly.
Cheers, Lajos