In Ext 4.0.0 you could do the following:

Code:
Ext.define('MyModel', {
    extend: 'Ext.data.Model',
    fields: [{
        name: 'id', type: 'integer',
        name: 'name', type: 'string'
    }]
});
var store = new Ext.data.Store({
    model: 'MyModel',
    filters: null
});
In 4.0.1, Ext.data.AbstractStore.decodeFilters() bombs out with "config is null". One has to set 'filters' to undefined to make it work again. This is a regression and change in behaviour that breaks our code. Please fix it.

This may also apply to other config properties, although I haven't checked that yet.

Thanks a lot in advance.