I'm using fragment activity on one project, but it seems v4 support FragmentActivity doesn't has getSupportActionBar() method, and I need to use the support one in order to use android.support.v7.app.ActionBar
The ActionBarActivity does support the method you require, and is a subclass of FragmentActivity. See: http://developer.android.com/reference/android/support/v7/app/ActionBarActivity.html