function manage_popup(id,lang,w,h){
  var left = Math.abs((w - screen.width) / 2);
  var top = Math.abs((h - screen.height) / 2);

  window.open("popup.php?id="+id+"&lang="+lang,"popup","width="+w+",height="+h+",left="+left+",top="+top);			
}