function getCookie(name)
{ var pos
  var token = name + "=";
  var tnlen = token.length;
  var cklen = document.cookie.length;
  var i = 0;
  var j;
  while (i < cklen)
  { j = i + tnlen;
    if (document.cookie.substring(i, j) == token)
    { pos = document.cookie.indexOf (";", j);
      if (pos == -1)
        pos = document.cookie.length;
      return unescape(document.cookie.substring(j, pos));
    }
    i = document.cookie.indexOf(" ", i) + 1;
    if (i == 0) break;
  } //End While
  return null;
}
function setCookie(name, value)
{ document.cookie = name + "=" + escape(value)
}
function deleteCookie(name)
{ var exp = new Date();
  exp.setTime (exp.getTime() - 1);
  var cval = getCookie (name);
  document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();

}