enter key

            {
                        xtype: 'textfield',
                        fieldLabel:'Password',
                        inputType:'password',
                        listeners:{
                            scope:this,
                            specialkey: function(f,e){
                                if(e.getKey()==e.ENTER){
                                    Ext.Msg.alert('Keys','You pressed the Enter key');
                                }
                            }
                        }

                    }