function openPage(x,y,s) {

var ileft, itop;

 ileft = screen.width/2 - x/2;
 itop = screen.height/2 - y/2;

         window.open(s, 'Message', 'fullscreen=no,toolbar=no,location=no,scrollbars=no,resizable=no,menubar=no,width=' + x + ',height=' + y + ',top='+itop+',left='+ileft)
         }