Android : Roboguice is not injecting dependencies

I'm using Roboguice to inject my dependencies but it's not workink. I have a class that extends RoboActivity and my attribute still null.

public class SplashActivity extends RoboActivity {

    @Inject
    private PropertyReader propertyReader;

    @Inject
    Vibrator v1;

}

Should i do some aditional config?

Thank in advance.