function updateSelector( classID, destinationID ){
	
	var o = $('#'+destinationID);
	var label = o.prev();
	$(' <span class="wait">Please, wait...</span>').appendTo(label);
	
	$.getJSON("do.action.php?module=class&action=get&cid="+parseInt(classID),
		function(data){
			$('#'+destinationID+" option:not([@value=''])").remove();
			for(var i in data.items)
				$("<option>").html(data.items[i]).attr("value", i).appendTo("#"+destinationID);
			$('.wait', label).remove();
		});
}