Android : Registering gcmregistrar.getregistrationid returns empty ID

Hello Android developers.

I have 2 Android applications with 2 different packages. I want to register both of my applications to Google. I have registered my apps using the same method. And both of my applications have GCMActivity ( All of you already know the code, I used the same code as all of you ).

But i am stuck in a condition where one of my applications can't get regId.

final String regId = GCMRegistrar.getRegistrationId(this);

I tried to debug my apps, and what I got is this : Application A gets the regId, but Application B only has "" value.

I don't understand what the problem is. Both of them have similar code, similar way to register to Google. Only different packages, SENDER_ID, GCMBroadcastReceiver, and Android key.

Is there a way my apps can get regId. It has been like a week, I tried to register it using different Google accounts and different PC's. But same result. I really need help.

Thank you.