function oddevenrows() {
	var tr = document.getElementsByTagName('tr');
	var len = tr.length;
	count = 0;
	for (var i=0;i<len;i++) {
		if (tr[i].parentNode.className == 'contenttable' || tr[i].parentNode.parentNode.className == 'contenttable') {
		tr[i].className = (count%2) ? 'even' : 'odd';
		count++;
		}
	}
}

window.onload = oddevenrows;