code: public void onTimerEvent(TimerEvent event, ActivityContextInterface aci) {
  		// detaching so the null AC is claimed after the event handling
  		aci.detach(sbbContext.getSbbLocalObject());
  		try {
  			DataSourceChildSbbLocalInterface child = (DataSourceChildSbbLocalInterface) getLocationChildRelation().create();
  			child.getBindings(getSender().getURI().toString());
  		} catch (Exception e) {
  			tracer.severe("failed to create sip registrar child sbb, to lookup the sender's contacts",e);
  			return;
  		}
  	}
docs: Event handler from the timer event, which signals that a message must be
  sent back to the UA
  
  @param event
  @param aci