[Toni Wilen]

It is not implemented:

int uae_slirp_redir(int is_udp, int host_port, struct in_addr guest_addr,
		    int guest_port)
{
#ifdef WITH_QEMU_SLIRP
	if (impl == QEMU_IMPLEMENTATION) {
		UAE_LOG_STUB("");
		return 0;
	}
#endif
#ifdef WITH_BUILTIN_SLIRP
	if (impl == BUILTIN_IMPLEMENTATION) {
		return slirp_redir(is_udp, host_port, guest_addr, guest_port);
	}
#endif
	return 0;
}