Quote Originally Posted by ap View Post
If you application extends some Ext panel and it has internally configured options (defaults) which does not require the 'new' call to pass any config options, you will still have to pass on a blank config object. Because the Ext.Compat intercepts the constructors before you component is called.

PHP Code:
someCustomCmp = new MyApp.MyPanel( {} );  //pass a blank obj, even if your custom obj contains all the required values to call it's parent component. 
Actually the compat layer should handle the case where the config is null, that's just an oversight. Thanks for pointing it out.