The well known Unix Client/Server Program Interface (UCSPI) from Dan Bernstein (UCSPI-TCP) and it's TLS encrypted 'brother' UCSPI-SSL is now completely IPv6 enforced. Though most of the development has been contributed by Felix von Leitner (fefe), now an integrated IPv4/IPv6 version does exist: * http://www.fehcom.de/ipnet/ucspi-tcp6.html * http://www.fehcom.de/ipnet/ucspi-ssl.html Both versions support Linux, *BSD, and MacOS X out of-the-box, however follow DJB slashpacket conventions and require compiling (gcc or clang) before use (usually just: package/install). I would be interested to get some reports regarding the IPv6 enhancements. Pls. send those to: feh@fehcom.de best regards. --eh.