sipProviderImpl.sipListener = null;
sipProviderImpl.removeListeningPoints();
	public void deleteSipProvider(SipProvider sipProvider)		throws ObjectInUseException {		if (sipProvider == null)			throw new NullPointerException("null provider arg");		SipProviderImpl sipProviderImpl = (SipProviderImpl) sipProvider;		if (sipProviderImpl.listeningPoint.messageProcessor.inUse()) {			throw new ObjectInUseException("Provider in use");		}		sipProviderImpl.sipListener = null;		//Bug reported by Rafael Barriuso		sipProviderImpl.stop();		sipProviders.remove(sipProvider);		if (sipProviders.isEmpty()) {			this.stopStack();		}	}