B.t.w., does anybody know of a good (up-to-date) source of information that
lists available IPv6 stack implementations ...
I checked the IPNG working group site
(http://www.ietf.org/html.charters/ipngwg-charter.html), but ...
Following the "Additional IPNGWG Page" link near the top of that page
will lead you toward
http://playground.sun.com/pub/ipng/html/ipng-implementations.html