function setMenuHeight()
        {
         var sNewHeight = document.getElementById("contenutoprincipale").offsetHeight;

         if (sNewHeight <= 535){

          document.getElementById("menu").style.height= "533px";
          document.getElementById("corpo").style.height= "527px";
         }
         else{

          document.getElementById("menu").style.height= eval(sNewHeight - 2)+"px";
         }
        }
  function centra(){         
    var margintop = Math.round((document.documentElement.clientHeight - 585)/2);
    document.getElementById("main").style.paddingTop = margintop+"px";
}