scanning a tree

Hi
I need to run an xsl stylesheet on my xml tree that do the following :

on every node in my xml tree I have a tag named 'modified' that tells me if
the current node has been modified.

I need to hold a flag that will tell me if one of the nodes has been
modified !

this flag will be the first tag in the  result tree:


      <modified> <xsl:copy-of select="$valueofFlag"/> </modified>



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