further to pgo's comment - this markup works for me:
Code:
<table style="width: 400px;">
<thead>
<tr> <th> head </th> </tr>
</thead>
<tbody style="height: 100px; overflow: auto;">
<tr> <th> .. </th> </tr>
<tr> <th> .. </th> </tr>
<tr> <th> .. </th> </tr>
<tr> <th> .. </th> </tr>
<tr> <th> .. </th> </tr>
<tr> <th> .. </th> </tr>
<tr> <th> .. </th> </tr>
<tr> <th> .. </th> </tr>
<tr> <th> .. </th> </tr>
<tr> <th> .. </th> </tr>
<tr> <th> .. </th> </tr>
</tbody>
</table>