My application works fine with ExtJS 4.1.3. With 4.2.0 and 4.2.1 I have a message : " TypeError: App is not a constructor http://localhost/extjs/ext-all-debug.js Line 7787 " This is an error [Stopper sur une erreur]

In fact my code is broken at line 7787 inside ext-all-debug.js : Ext.app.Application.instance = new App();

With ExtJS 4.1.3 an application is generated like this (line 6926):
Ext.onReady(function() {
new Ext.app.Application(config);
});
and it works fine.

I start my application from Application.js :

Ext.Loader.setConfig({enabled:true});

Ext.application({
name: '
Motile',
appFolder: '
app',
autoCreateViewport:
true,

requires: [
'Motile.view.Viewport',
'Motile.view.NavigationView'
,'Motile.view.ResourcesTemplatesView'

],


controllers: [
'ProjectTree',
'ProjectsCatalog',
'FrontController',
'TemplatesTree',
'StaffGrid',
'EqpTreeGrid',
'ResourcesGroups',
'AbilitiesGridController',
'ResourceAbilitiesGridController',
'ItemsGridController'
]

,models: [
'AbilitiesModel'
,'EqpModel'
,'ItemsModel'
,'ProjectModel'
,'ProjectsCatalog'
,'ResourceAbilitiesModel'
,'ResourcesGroupsModel'
,'StaffModel'
,'TemplatesModel'
]

,stores: [
'AbilitiesStore'
,'EqpStore'
,'ItemsStore'
,'ProjectStore'
,'ProjectsCatalog'
,'ResourceAbilitiesStore'
,'ResourcesGroupsStore'
,'StaffStore'
,'TemplatesStore'
]
});