<xs:schema

      targetNamespace="http://madskills.com/public/xml/rss/module/trackback/"
      xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="ping" type="xs:anyURI">
  <xs:annotation>
    <xs:documentation>
      <![CDATA[The trackback:ping is this feed item's TrackBack url.]]>
    </xs:documentation>
  </xs:annotation>
</xs:element>
<xs:element name="about" type="xs:anyURI">
  <xs:annotation>
    <xs:documentation>
      <![CDATA[The trackback:about is the original item that was pinged, letting the original author know that the information was syndicated using a TrackBack.]]>
    </xs:documentation>
  </xs:annotation>
</xs:element>

</xs:schema>