You have an extra TD in each of your rows below your rowspans. You want the HTML to look like this: 
<table border=1>
<tr>
  <td rowspan=2>foo1</td>
  <td>bar1</td>
</tr>
<tr>
  <td>bar2</td>
</tr>
<tr>
  <td rowspan=2>foo2</td>
  <td>bar3</td>
</tr>
<tr>
  <td>bar4</td>
</tr>
</table>

[download]
Notice how bar2 and bar4 have only one TD in the row.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to Re: Using rowspan with CGI.pm by merlyn
in thread Using rowspan with CGI.pm by loris

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