FXSL library

dear All,

I am trying to get the FXSL library library to work but I get an error in
strSplit-to-Words.xsl: 

Error in XPATH expression, function not in namespace

<xsl:variable name="vArg1" select="vendor:nodeset($arg1)"/>

does anyone recognise this error?

this is the style sheet declaration:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"  
xmlns:msxsl="urn:schemas-microsoft-com:xslt"
xmlns:vendor="http://xml.apache.org/xalan"  >

thanks

kent gibson