function hidediv(id) {
   //safe function to hide an element with a specified id
   if (document.getElementById) { // DOM3 = IE5, NS6
      document.getElementById(id).style.display = 'none';
   }
   else {
      if (document.layers) { // Netscape 4
         document.id.display = 'none';
      }
      else { // IE 4
         document.all.id.style.display = 'none';
      }
   }
}

function showdiv(id) {
   //safe function to show an element with a specified id
   if (document.getElementById) { // DOM3 = IE5, NS6
      document.getElementById(id).style.display = 'block';
   }
   else {

     if (document.layers) { // Netscape 4
         document.id.display = 'block';
      }
      else { // IE 4
         document.all.id.style.display = 'block';
      }
   }
}