<!DOCTYPE informaltable PUBLIC "-//OASIS//DTD DocBook V3.1//EN">
<!-- entrytbl not supported, fake it in descrip.1 -->
<informaltable frame=all>
<tgroup cols=3>
<tbody>
<row>
  <entry>a1</entry>
  <entry>b1</entry>
  <entry>c1</entry>
</row>
<row>
  <entry>a2</entry>
  <entrytbl cols=3>
    <tbody>
      <row>
        <entry>b2a1</entry>
        <entry>b2b1</entry>
        <entry>b2c1</entry>
      </row>
      <row>
        <entry>b2a2</entry>
        <entry>b2b2</entry>
        <entry>b2c2</entry>
      </row>
      <row>
        <entry>b2a3</entry>
        <entry>b2b3</entry>
        <entry>b2c3</entry>
      </row>
    </tbody>
  </entrytbl>
  <entry>c2</entry>
</row>
<row>
  <entry>a3</entry>
  <entry>b3</entry>
  <entry>c3</entry>
</row>
</tbody>
</tgroup>
</informaltable>