Adding style to sortable column

Adding style to sortable column

I have this code:
<table id="table">
<thead>
<tr>
<th>Column 1</th>
<th>Column 2</th>
</tr>
</thead>
<tbody>
<tr>
<td>...</td>
<td>...</td>
</tr>
...
</tbody>
</table>
<script type="text/javascript">
$("#table").tablesorter();
</script>
How can I add special selector to sortable column's tag?