function zebra(){
	var list = document.getElementsByTagName('TABLE');

	for(var i = 0, l = list.length; i < l; i++)
		if(list[i].id.substr(0, 5) == 'zebra'){
			var rows = list[i].getElementsByTagName('TR');
		    if(!rows) return;

			for(var j = 0, k = rows.length; j < k; j++)
				if(j % 2 == 0) rows[j].className += 'grey';
		}
}




add_handler(window, 'load', function(){zebra()});