function extrawindow(Url, width, height, top, left, buttons ) {
   style = "";
   if( width > 0 && height > 0)
     style = style + "height=" + height + ",width=" + width + ", ";
  
   style = style + "top=" + top + ", left=" + left + ",status=no,menubar=" + buttons + ",toolbar="+ buttons + ",location=no,scrollbars=yes,resizable=yes";
   var popup = window.open( Url,"", style );
   popup.focus();
}