JQuery dialog is not displayed with ajax in the IE

$('#package').sSelect().change(function(){


                $.ajax({
                    url: 'scripts/change_script.php',
                    type: 'POST',
                    dataType: 'json',
                    data:{account_id:2},
                    beforeSend: function() {
                        $( "#wait_dialog" ).dialog( "open" );
                    },
                    success: function(data) {
                        if(data.success)
                        {
                            location.reload();
                        }
                        else
                        {

                        }
                    }
                });

                return false;
            });

this code work with Firefox, chrome but dialog is not display开发者_如何学运维ed for IE. can anybody help me?

hi if you are using jquery 1.4.2 this SO question jQuery ajaxSetup beforeSend not executing in IE8 might be of interest to you.