code: @Override
  	public void onError(Context context, String errorId) {
  		if(logger != null) {
  			logger.error("GCM registration failed with error: " + errorId);
  		}
  		
  		if(notificationCallback != null) {
  			notificationCallback.onError(context, errorId);
  		}
  		else {
  			logWarn("No notificationCallback found in GCM receiver.  Initialization may have failed.");
  		}			
  	}
docs: /* (non-Javadoc)
  @see com.socialize.notifications.C2DMReceiverHandler#onError(android.content.Context, java.lang.String)