JTable jquery, Close Child button

Question

I am using Jtable (Jquery based). I have some trouble with the child table. In the child table I added a new button in the toolbar. With this new button in the toolbar, che close icon disappear, how can I fix it? (if I remove the toolbar element the X of close button is correctly displayed).

            $('#ListHeader').jtable({
                    title: 'ExpensesAccounts' ,
                    actions: {
                        listAction: function (postData, jtParams) {
                            return getListDataHeader();
                        }
                    },
                    fields: {
                        ID:{
                            key: true,
                            list:false
                        },
                        Details: {
                            title: '',
                            width: '5%',
                            sorting: false,
                            edit: false,
                            saveUserPreferences: false,
                            create: false,
                            display: function (headerData) {
                                //Create an image that will be used to open child table
                                var $img = $('<img src="../Images/viewDetails.png" width="20p" height="20p" title="View Details" />');
                                //Open child table when user clicks the image
                                $img.click(function () {
                                    $('#ListHeader').jtable('openChildTable',
                                            $img.closest('tr'),
                                            {
                                                title: headerData.record.Title + ' - Row' ,
                                                saveUserPreferences: false,
                                                paging: true,
                                                pageSize: 3,
                                                showCloseButton:true,
                                                toolbar: {
                                                    items: [{
                                                        icon: '../scripts/jtable/themes/metro/add.png',
                                                        text: 'Add New Row',
                                                        click: function (headerID) {
                                                            window.location = "InsertRow.aspx";
                                                        }
                                                    }]
                                                },
                                                actions: {
                                                    listAction: function (postData, jtParams) {
                                                        return getListDataRow(headerData.record.ID, jtParams.jtStartIndex, jtParams.jtPageSize);
                                                        //return { "Result": "OK", "Records": [] };
                                                    },
                                                    deleteAction: function (postData) {
                                                        return deleteItem(postData, 'Expense Account Rows');
                                                    }
                                                },
                                                fields: {
                                                    HeaderID: {
                                                        type: 'hidden',
                                                        defaultValue: headerData.record.ID
                                                    },
                                                    ID: {
                                                        key: true,
                                                        create: false,
                                                        edit: false,
                                                        list: false
                                                    },
                                                    Title: {
                                                        title: 'Title',
                                                        width: '20%'
                                                    }
                                                }
                                            }, function (data) { //opened handler
                                                data.childTable.jtable('load');
                                            });
                                });
                                //Return image to show on the person row
                                return $img;
                            }
                        },
                        Title: {
                            title: 'Title'
                        },
                        Status: {
                            title: 'Status',
                            width: '8%'
                        }
                    }
                });
                $('#ListHeader').jtable('load');

Thanks, Nk