RE: problem using dyn:evaluate with MSXML

Hello,

I use Jeni Tennison's code given in a thread to implement an evaluate()
fonction :

<xsl:stylesheet version="1.0"
                xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                xmlns:dyn="http://exslt.org/dynamic"
                xmlns:msxsl="urn:schemas-microsoft-com:xslt"
                extension-element-prefixes="dyn msxsl">

<msxsl:script implements-prefix="dyn" language="jscript">
   function evaluate(context, expression)
      {
         return context.nextNode().selectNodes(expression);
      }
</msxsl:script>

...

</xsl:stylesheet>

I define a variable $y containing an Xpath expression laike this :

	<xsl:variable name="y" select"'@my_attribute'">

Calling
	 <xsl:value-of select="dyn:evaluate(., $y)"/>
works fine and give me the attribute value.

The problem I have is that when I define $y like this :

	<xsl:variable name="y">@num</xsl:variable>

(Which is to me exactly the same definition as before)
then I get a error !
The HTML page cannot be loaded. The message error is in French :

"Type d'erreur :
msxml3.dll (0x80020009)
Erreur d'exicution Microsoft JScript Type incompatible ligne = 4, col = 10
(la ligne est dicalie ` partir du dibut du bloc de script).
Erreur renvoyie par l'appel de mithode ou de propriiti."

My XML parser is MSXML3
XML/XSL to HTML transform is performed with asp vb script using DOM

$y is calculated so I cannot write it directly within the "select". It can
be any Xpath (not only attribute name, so I can't use local-name()=$y)

As somebody Ideas about this ?

Matthieu.