Calling .net CLR methods from Saxon

saxon_xslt_dotnet.xslt

<xsl:transform version="2.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:saxon="http://saxon.sf.net/">
  <xsl:output method="text"/>
  <xsl:template match="/">
    <xsl:text>asdf</xsl:text>
    <out xmlns:env="clitype:System.Environment" xmlns:os="clitype:System.OperatingSystem">
      <xsl:value-of select="env:Version()"/>
    </out>
    <xsl:text>asdf</xsl:text>
  </xsl:template>
</xsl:transform>