<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">

<head>
<script>
function boom()
{
  var td = document.createElementNS("http://www.w3.org/1999/xhtml", "td");
  td.appendChild(document.createTextNode("b"));
  document.getElementById("tbody").appendChild(td);
}
</script>
</head>

<body>

<table border>
  <tbody id="tbody">
    <tr>
      <td rowspan="0">a</td>
    </tr>
    <tr>
    </tr>
  </tbody>
</table>

<script>
  // Flush layout
  document.body.offsetWidth;

  boom();
</script>

</body>
</html>