title: Android duplicate registration id for different devices
body: <p>I am seeing this issue on my push notifications server - different Android devices (identified by their IMEI) receive the SAME registration id from Google's GCM service.
  Isn't the registration id supposed to be unique? at east for the same application or GCM API Key?</p>
  
  <p>I saw this thread but there doesn't seem to be an answer there:
  <a href="https://stackoverflow.com/questions/18685755/can-two-different-devices-have-same-gcm-registration-id">Can two different devices have same GCM Registration ID?</a></p>
  
  <p>Any help would be much appreciated</p>
  
  <p><strong>EDIT</strong>
  here is the relevant code for registration:</p>
  
  <pre><code> Intent intent = new Intent(
                                     "com.google.android.c2dm.intent.REGISTER");
                     intent.setPackage("com.google.android.gsf");
                     intent.putExtra("app",
                                     PendingIntent.getBroadcast(context, 0, new Intent(), 0));
  
                     intent.putExtra("sender", flatSenderIds);
                     context.startService(intent);
  </code></pre>