// set cookie optional expire
  function setCookie(name, value, expire, path) {
    document.cookie = name + "=" + escape(value)
    + ((expire == null) ? "" : ("; expires=" + expire.toGMTString()))
    + (path ? ("; path=" + path) : "" );
  }

  // get cookie value
  function getCookie(Name) {
    var search = Name + "="
    if (document.cookie.length > 0) { // if there are any cookies
      offset = document.cookie.indexOf(search)
      if (offset != -1) { // if cookie exists
      offset += search.length
      end = document.cookie.indexOf(";", offset)
        if (end == -1)
         end = document.cookie.length
        return unescape(document.cookie.substring(offset, end))
      }
    } else {
      return false;
    }
  }

  function SetReferrerCookie() {
    var expires = new Date();
    if (expires.getFullYear) {
       var year = expires.getFullYear();
       expires.setFullYear(year + 1);
    } else {
      var year = expires.getYear(); 
      expires.setYear(year+1);
    }  
    //referrer must be set and different from local host
    if ( document.referrer && ( (document.referrer.indexOf(window.location.host) == -1) || (document.referrer.indexOf(window.location.host) > 15)) 
         &&  (getCookie('tid') == false) ) setCookie('tid', document.referrer, expires, '/');     
  }
  if (navigator && navigator.cookieEnabled) SetReferrerCookie();