function reColorTables(contentId) {

var content = document.getElementById(contentId);

var tables = content.getElementsByTagName("table");
	for ( var k = 0; k < tables.length; k++ ) {
			var rows = tables[k].getElementsByTagName("tr");
			for ( var i = 0; i < rows.length; i += 2 )
			rows[i].className += " darktr"
			for ( var i = 1; i < rows.length; i += 2 )
			rows[i].className += " lighttr"
	}			
}