Mine

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
	"http://www.w3.org/TR/html401/strict.dtd">
<html>
	<head>
		<title>Test</title>
		<meta http-equiv="Content-Type" content="text/html;charset=utf-8">
		<style type="text/css">
		tr {
			background-color: #00FF00;
		}
		.odd {
			background-color: #FF0000;
		}
		</style>
		
		<script type="text/javascript" language="JavaScript">
		var OldColor;
		function ColorRow ( )
		{
			OldColor = this.style.backgroundColor;
			this.style.backgroundColor = "#DD0000";
		}

		function ResetColor ( )
		{
			this.style.backgroundColor = OldColor;
		}

		function load ( )
		{
			var el = document.getElementById ( 't' ).getElementsByTagName ( 'tr' );
			for ( var i = 0; i < el.length; i++ ) {
				if(window.addEventListener) {
					el[i].addEventListener('mouseover', ColorRow, 0 );
					el[i].addEventListener('mouseout', ResetColor, 0 );
				} else {
					el[i].attachEvent('mouseover', ColorRow );
					el[i].attachEvent('mouseout', ResetColor );
				}
			}
		}
		</script>
	</head>

	<body onload="load();">
		<table id="t">
			<tr>
				<th>Name</th>
				<th>Age</th>
				<th>Sex</th>
			</tr>

			<tr class="odd">
				<td>Eric</td>
				<td>12</td>
				<td>Male</td>
			</tr>

			<tr>
				<td>George</td>
				<td>13</td>
				<td>Male</td>
			</tr>

			<tr class="odd">
				<td>Lisa</td>
				<td>11</td>
				<td>Female</td>
			</tr>

			<tr>
				<td>Sarah</td>
				<td>12</td>
				<td>Female</td>
			</tr>

			<tr class="odd">
				<td>Hannah</td>
				<td>13</td>
				<td>Female</td>
			</tr>
		</table>
	</body>
</html>