Ext Base to speed up development?

Hello guys,

i tried to use ext-base to speed up development, but got the following error:

Titanium.include('libraries/extjs/adapter/ext/ext-base.js');
 
Error:
[6,0] file:///android_asset/Resources/.../ext/ext-base.js
Message:
Too deep recursion while parsing

Perhaps you know the recursive object notation from ExtJS this is very effective for writing large and complex interfaces.

Example:

var mainWindow = Titanium.UI.createTabGroup({
    tabs : [
        {  
            xtype : 'tab',
            icon:'KS_nav_ui.png',
            title:'Contacts',
            window:{  
                xtype : 'panel',
                title:'Tab 1',
                backgroundColor:'#fff'
            })
        },
        {  
            xtype : 'tab',
            icon:'KS_nav_views.png',
            title:'Contacts',
            window:{  
                xtype : 'panel',
                title:'Tab 2',
                backgroundColor:'#fff'
            }
        }
    ]
});
mainWindow.open();

Thanks for any hint.

Best regards Kay