function xdrJsonp(url, a, b){
        var options, fn;
        if (typeof a === 'function') {
            fn = a; options = {};
        } else if (typeof a === 'object' && a.constructor.toString().slice(9, 17) === "Object()") {
            options = a;
            if (typeof b !== 'function') {
                throw Error("xdrJsonp: jsonp callback expected!!!");
            }
            fn = b;
        } else {
            throw Error("xdrJsonp: illegal arguments!!!");
        }

        var proxy = options.proxy || xdrJsonp.PROXY;
        var format = options.format || "json";

        var call = "call_"+ (new Date).getTime().toString().slice(0,-3)+Math.random().toString().replace(/\./g,"");
        var headID = document.getElementsByTagName("head")[0];
        var script = document.createElement('script');

        script.id = call;
        script.type = 'text/javascript';

        xdrJsonp.callbacks[script.id] = fn;

        var query = {
           "url": url, "format":format, "callback":"xdrJsonp.invokeById('"+script.id+"')"
        };

        var temp = [];
        for (var i in query) temp.push(i + '=' + encodeURIComponent(query[i]));

        script.src = proxy + '?' + temp.join('&');
        headID.appendChild(script);
}
xdrJsonp.PROXY = "http://127.0.0.1:8898/";
xdrJsonp.callbacks = {};
xdrJsonp.invokeById = function(id){
        var e = document.getElementById(id);
        var t = xdrJsonp.callbacks[id];
        e.parentNode.removeChild(e);
        delete xdrJsonp.callbacks[id];
        return t;
};