примерно так ...
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
<style type="text/css">
td{
height: 20px; width: 150px; border: solid #000000 1px
}
</style>
</head>
<body>
<table id="tb">
<tr>
<td><div><span></span></div></td>
<td><div><span></span></div></td>
<td><div><span></span></div></td>
<td><div><span></span></div></td>
</tr>
<tr>
<td><div><span></span></div></td>
<td><div><span></span></div></td>
<td><div><span></span></div></td>
<td><div><span></span></div></td>
</tr>
</table>
<script language="JavaScript" type="text/javascript">
var tb = document.getElementById("tb");
tb.onclick = function (a) {
if (!a) a = window.event;
a = a.target || a.srcElement;
if (a.tagName == "TD") a.getElementsByTagName('span')[0].innerHTML = "\u0412\u0441\u044f\u043a\u0438\u0435 \u0440\u0430\u0437\u043d\u044b\u0435 \u0441\u043b\u043e\u0432\u0430";
};
</script>
</body>
</html>