serverSync: serverTime Function return value from server but I have checked both server and client time both are same.When i called server to sync with server it will not display countdown. help me ?

    $(function() {
        var shortly = new Date();
        var newTime = new Date('April 9, 2010 20:38:10');
        //for loop divid
        /// 
        $('#defaultCountdown').countdown({
            until: shortly, onExpiry: liftOff, onTick: watchCountdown, serverSync: serverTime
        });
        $('#div1').countdown({ until: newTime });
    });
    function serverTime() {
        var time = null;
        $.ajax({
            type: "POST",
            //Page Name (in which the method should be called) and method name
            url: "Default.aspx/GetTime",
            // If you want to pass parameter or data to server side function you can try line
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            data: "{}",
            async: false,
            //else If you don't want to pass any value to server side function leave the data to blank line below
            //data: "{}",  
            success: function(msg) {
                //Got the response from server and render to the client

                time = new Date(msg.d);
                alert(time);
            },
            error: function(msg) {
                time = new Date(); 
                alert('1');
            }
        });
        shortly = time;
        return time;

    }