code: private void proxyTo(final SipURI destination, final SipRequest msg) {
          final Connection connection = this.stack.connect(destination.getHost(), destination.getPort());
          final ViaHeader via =
                  ViaHeader.with().host("127.0.0.1").port(5060).transportUDP().branch(ViaHeader.generateBranch()).build();
          msg.addHeaderFirst(via);
          connection.send(msg);
      }
docs: Whenever we proxy a request we must also add a Via-header, which essentially says that the
  request went "via this network address using this protocol". The {@link ViaHeader}s are used
  for responses to find their way back the exact same path as the request took.
  
  @param destination
  @param msg