var _source;
            var _popup;
            function showConfirm(source) {
                     this._source = source;
                    this._popup = $find('popup');
                    //  show the popup
                    this._popup.show();
            }
            function okClick() {
                if(this._popup) {
                    this._popup.hide();
                }
               location = "logoff.aspx";   
            }
            function cancelClick() {
                if(this._popup) {
                    this._popup.hide();
                }
                this._source = null;
                this._popup = null;}