public static SipResponse createResponse(SipRequest request,String localTag,int code) throws PayloadException {
  return createResponse(request,localTag,code,null);
}

public static SipResponse createResponse ( SipRequest request , String localTag , int code ) throws PayloadException { return createResponse ( request , localTag , code , null ) ; }
works just like sipresponse createresponse ( siprequest request , string localtag , int code , string warning ) except the warning is always null
