function openWindow(nome_pagina,winName,width,height)
   {
   x = (800 - width)/2;
   y = (600 - height)/2;
   if (screen)
      {
      y = (screen.height - height)/2;
      x = (screen.width - width)/2;
      }
   window.open(nome_pagina,winName,'width='+width+',height='+height+',screenX='+x+',screenY='+y+',top='+y+',left='+x);
   }
   
   function MM_openBrWindow(theURL,winName,features) { //v2.0
     window.open(theURL,winName,features);
   
}