estriction&gt;
  &lt;/xs:simpleType&gt;

  &lt;!-- version can contain one or more of alphanumeric characters and symbols '_' '-' '.' 
       Allows specifing a version range: minVersion : maxVersion
  --&gt;
  &lt;xs:simpleType name="VersionRangeType"&gt;
    &lt;xs:restriction base="xs:string"&gt;
      &lt;xs:pattern value="[0-9]+.[0-9]+((.[0-9]+)|())((\-[0-9A-Za-z_\-\.]+)|([_A-Za-z][0-9A-Za-z_\-\.]*)|())((\+[\-\._A-Za-z0-9]+)|())((:[0-9]+.[0-9]+((.[0-9]+)|()))|())((\-[0-9A-Za-z_\-\.]+)|([_A-Za-z][0-9A-Z