Datepicker animation problem - jquery-1.5.1

Datepicker animation problem - jquery-1.5.1

Hi,

I hope I have posted in the right area, not sure if datepicker is part of jquery or a plugin...

The problem I have is as soon as I add an animation to datepicker it stops working. You cannot open the datepicker anymore.

The code I have is very simple:

$(function()
    {
        /* Add menu bar at bottom of the picker */
        $( "#datepicker" ).datepicker({
            showButtonPanel: true,
            showOn: "button",
            buttonImage: "img/calendar.gif",
            buttonImageOnly: true
        });
       
        /* Change date output format */
        $.datepicker.setDefaults({
        dateFormat: 'dd-mm-yy',
        showAnim: 'fold'
        });

    }); 


Any ideas would be greatly appreciated  :)