match with mode does not match

[Mansour <mansour77@yahoo.com>]

I am trying t use mode with programlisting to treat the contents in a 
different way. Here's a piece of my document:

<example>
     <title>webapp/WEB-INF/web.xml</title>
     <programlisting mode="format-xml">
         <xi:include href="files/web.xml" />
    </programlisting>
</example>

Now in my customization layer I have:

    <xsl:template match="programlisting" mode="format-xml" priority="9.0">
        <xsl:apply-templates   mode="format-xml" />
    </xsl:template>

But it's not matching. I changed the value of the priority. I have even 
commetted out the apply-templates element just to see if there will be 
an output. It's not matching at all. What am I doing wrong?