var popup_window = null;
function popup(p, w, h, a)
{
	if (popup_window != null && !popup_window.closed)
	{
		popup_window.close();
	}
	popup_window = window.open(a + "popup.php?t=" + p, "popup", "width=" + w + ",height=" + h +  ",scrollbars=no,resizable=no,toolbar=no,directories=no,location=no,menubar=no,status=no,left=0,top=0");
	popup_window.focus();
	return false;
}