public Date engineGetCreationDate(String alias) {
      if (!loaded) {
         throw NOT_LOADED;
      }
      if (keyring == null) {
         return null;
      }
      List entries = keyring.get(alias);
      if (entries.size() == 0) {
         return null;
      }
      for (Iterator it = entries.iterator(); it.hasNext(); ) {
         Object o = it.next();
         if (o instanceof PrimitiveEntry) {
            return ((PrimitiveEntry) o).getCreationDate();
         }
      }
      return null;
   }