> What Saxon 6.5.3 produces:
>
>   <?xml version="1.0" encoding="utf-8"?>
>   <emit:stylesheet xmlns:emit="http://www.w3.org/1999/XSL/Transform"
>                    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
>                    version="1.0">
>      <emit:output method="xml" indent="yes"/>
>      <emit:template match="/">
>         <foo/>
>      </emit:template>
>   </emit:stylesheet>

If you take this and put it in a document you will see that it is a valid
XSLT document.
The important thing is not the prefix but the namespace the prefix is mapped
to.
Note that Xalan 2.5.1 gives you the same result.

If you like to get the output with xsl as prefix then write your stylesheet
using a different prefix, xslt for instance, and use xsl for the output:

<xslt:stylesheet version="1.0"
xmlns:xslt="http://www.w3.org/1999/XSL/Transform" xmlns:xsl="map_to_xsl">
  <xslt:output method="xml" indent="yes"/>
  <xslt:namespace-alias stylesheet-prefix="xsl" result-prefix="xslt"/>
  <xslt:template match="/">
    <xsl:stylesheet version="1.0">
      <xsl:output method="xml" indent="yes"/>
      <xsl:template match="/">
        <foo/>
      </xsl:template>
    </xsl:stylesheet>
  </xslt:template>
</xslt:stylesheet>

Best Regards,
George
-------------------------------------------------------
George Cristian Bina mailto:george@xxxxxxxxxxxxx
<oXygen/> XML Editor and XSLT Editor/Debugger
www.---.com/