ClientEvent onEdit arguments all undefined (mode, dataItem, etc)

Hi,

     I tried to intercept "Edit" ClientEvent and argument properties are all undefined.  

 Here is the function and alerts are displayed, so I know the event is called.  What did I miss?

Thank you

        function onEdit(e)
        {
            alert(e.dataItem);
            alert(e.mode);
            alert(e.form);
            alert(e.isNew);
            if (e.mode == "edit" && (typeof e.dataItem != 'undefined') && (e.dataItem != null)) {
                alert('a');
                $(e.form).find('#Description').hide();
            }

        }