<schema
    xmlns='http://www.w3.org/2001/XMLSchema'
    targetNamespace='http://www.w3.org/namespace/'
    xmlns:t='http://www.w3.org/namespace/'>

  <element name='ex1'>
    <complexType>
      <sequence>
        <element ref='t:x'/>
      </sequence>
    </complexType>
  </element>

  <element name='x'>
    <complexType mixed='true'>
    </complexType>
  </element>
</schema>
