Intercepted private observer method throws IllegalAccessError if notified within invocation of another business method of the declaring bean

@ApplicationScoped
@SomeInterceptorBinding // -> observer method is intercepted
public class Foo {

    @Inject
    Event<Payload> event;

    private void foo(@Observes Payload payload) {
        // do something
    }

    // foo() notified within invocation of fireEvent()
    public void fireEvent() {
        event.fire(new Payload());
    }
}