Actually, now that I think about it, td:hover isn't supported in some browsers. However, what will work with any browser is onmouseover and onmouseoff.
ex:
HTML Code:
<style>
td.navon {
background-color: #999999;
cursor: hand}
td.navoff {
background-color: #FFFFFF}
</style>
<table>
<tr>
<td class="navoff" onmouseover="className='navon'" onmouseoff="className='navoff'">
td 1
</td>
</tr>
<tr>
<td class="navoff" onmouseover="className='navon'" onmouseoff="className='navoff'">
td 2
</td>
</tr>
</table>
http://codingforums.com/showthread.php?t=1041