function zebraTable(t) {
	var i, odd = true;
	for (i=0; i<t.rows.length; i++) {
		if(t.rows[i].className!="nozebra") {
            t.rows[i].className += odd ? ' odd' : ' even';
            odd = !odd;
        }
	}
}
function zebra(id) {
	var t = document.getElementById(id);
	if (t) zebraTable(t);
}