function getCookie(name)
{
    var dc = document.cookie;
    var prefix = name + "=";
    var begin = dc.indexOf("; " + prefix);
    if (begin == -1)
    {
        begin = dc.indexOf(prefix);
        if (begin != 0) return null;
    }
    else
    {
        begin += 2;
    }
    var end = document.cookie.indexOf(";", begin);
    if (end == -1)
    {
        end = dc.length;
    }
    return unescape(dc.substring(begin + prefix.length, end));
}

function setCookie (name, value) {
 var argv = setCookie.arguments;
 var argc = setCookie.arguments.length;

 var expires = (argc > 2) ? argv[2] : null;
 var path = (argc > 3) ? argv[3] : '/';
 var domain = (argc > 4) ? argv[4] : null;
 var secure = (argc > 5) ? argv[5] : false;
 document.cookie = name + "=" + escape (value) +
   ((expires == null) ? "" : ("; expires=" + expires.toGMTString())) +
   ((path == null) ? "" : ("; path=" + path)) +
   ((domain == null) ? "" : ("; domain=" + domain)) +
   ((secure == true) ? "; secure" : "");
}

function deleteCookie (name) {
 var exp = new Date();
 exp.setTime (exp.getTime() - 720000);
 var cval = getCookie (name);
 document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();
}