Customizing book/bookinfo/pubdate

Hello all,

I'm trying to insert the date of processing into the pubdate tag, but it 
doesn't work as it should:

1. In /book/bookinfo/ I have the pubdate tag. 

2. In my Makefile I have this:

xsltproc --stringparam processingDate "$(shell date '+%Y/%m')" \

The param is correctly passed into my stylesheet.

3. The template which is to insert the date, looks like this:
   <xsl:template match="pubdate">
      <xsl:with-param name="date" select="$processingDate"/>
      <xsl:message>Match! pubdate</xsl:message>
      <xsl:value-of select="$date"/>
   </xsl:template>

But it doesn't hit. However, if I put the pubdate in any other arbitrary 
element, such as a sect1, the template matches. I have the same problem 
with /book/bookinfo/title

I guess this is caused by I don't grasp XSL correctly: A docbook template hits 
pubdate, and then the node(pubdate) is not any longer available in the 
document.

How do I do this customization correctly? Is there some pattern for overriding 
templates/modifying documents?


Cheers,

			Frans