Extjs - Additional values to a Ext.Msg.Show (cheating scope)

   // following example comes from a drag drop implementation in a grid, which
   // requires a YES/NO answer on a messagebox, but we would like to add some
   // extra's as a parameter to the function where we test the answer
 
 
   /*--------------------------------------------------------------------------
     * Drag and Drop event Handlers
     *-------------------------------------------------------------------------*/
 
    ProcessDropping : function (ddSource, data, obj) {
 
        Ext.Msg.show({
            title     : zap.getLang('plan', 'delete_event','Ereignis zufügen?'),
            msg       : zap.getLang('plan', 'q_delete_event','Soll dieses Ereignis zugefügt werden?'),
            buttons   : Ext.Msg.YESNO,
            config    : {
            	obj    : obj,
            	myname : 'nobody'
            },
            fn        : this.ProcessDroppingContinue,
            icon      : Ext.MessageBox.QUESTION
        });
    },
 
    ProcessDroppingContinue : function (btn, text, opt ) {
        var obj = opt.config.obj;      // = obj from the parameters of the other routine
        var cowboy = opt.config.myname // = nobody
 
        if (btn === 'yes' ) {
            // do something very nice here
        }
    }