function setCookie(name, value, expiration)
{
   var exp_str = '';
   if (expiration)
   {
      var exp_date = new Date();
      exp_date.setDate(exp_date.getDate() + expiration);
      exp_str = ';expires=' + exp_date.toGMTString();
   }
   document.cookie = name+ '=' + escape(value) + exp_str;
}

function getCookie(name)
{
   if (document.cookie.length > 0)
   {
      var start = document.cookie.indexOf(name + '=');
      if (start >= 0)
      { 
         start += name.length + 1; 
         var end = document.cookie.indexOf(';', start);
         if (end == -1)
         {
            end = document.cookie.length;
         }
         return unescape(document.cookie.substring(start, end));
      } 
   }

   return '';
}

function deleteCookie(name)
{
   setCookie(name, '', -1);
}