<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                xmlns:msxsl="urn:schemas-microsoft-com:xslt"
                xmlns:js="urn:js"
                version="1.0">
  <xsl:template match="/">
    <xsl:element name="xsl:stylesheet">
      <xsl:attribute name="version">1.0</xsl:attribute>
           ...Тут много всякого...
      </xsl:element>
    </xsl:template>
</xsl:stylesheet>

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet 
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:xsla="http://www.w3.org/1999/XSL/Transform/alternate"
  version="1.0"
  xmlns:msxsl="urn:schemas-microsoft-com:xslt"
  xmlns:php="http://php.net/xsl"
  xmlns:func="http://exslt.org/functions"
  xmlns:common="http://exslt.org/common"
  xmlns:custom="http://custom"
  >
  
  <xsl:namespace-alias stylesheet-prefix="xsla" result-prefix="xsl"/>
  
  <xsl:template match="/">
    <xsla:stylesheet xmlns:msxsl="urn:schemas-microsoft-com:xslt" version="1.0">
      <xsla:apply-template select="msxsl:node-set(.)"/>
    </xsla:stylesheet>
  </xsl:template>

</xsl:stylesheet>