var ven;

function popup(url, title){ 
 if (ven!=null){ven.close();ven=null;}
 ven = window.open(url,title,"scrollbars=1, channelmode=0, resizable=0, fullscreen=0, location=0, directories=0, menubar=0, toolbar=0, statusbar=0, width=610, left=200, top=200, height=500, dependent=1");
 ven.focus();
}