try this

<td class="bildlink"><a href="http://www.jakobgrannas.com/portfolio/Client%20work/Asian%20dating/homepage%20copy.png"><img src="thumbs/asiandating.jpg" width="70" height="70" alt="" class="thumbsleft"></a></td>

.bildlink a {
border:1px solid #color;
}

.bildlink a:hover {
border:1px solid #hovercolor;
}