* jjmenu library file has to be modified in order to handle some error cases.
* see line 87 in jjemenu.js. Following code was added:

/* jjmenu doesn't provide ability to add callback function
in case of error. So the error handling has to be included in
the library itself */
if(data.show_error == true){
    alert("The show doesn't exist anymore!");
    window.location.reload();
}else if(data.playlist_error == true){
    alert("The playlist doesn't exist anymore!");
    window.location.reload();
}