Robert Andersson

Minecreaft Launcher 1.3.6 bootstrap 5 still has the problem "protocol family unavailable"
(Game version 1.7.2)

OK, I yield.
I have no problem to understand what the server says.

But in my heart I still think "[/2001:0:0:0:0:0:0:6:52085]" and "2001::6:25565" are two really strange syntax(es)

and that http://tools.ietf.org/html/rfc4291#section-2.2 has no notion of "port"

WORKAROUND: It's the launcher that creates the problem !!
Use MagicLauncher_1.0.0 or the old Minecraft.exe launcher (unknown
version, but downloaded the first quarter of year 2012)

After launching 1.5 or 1.5.1 there is no problems entering IPv6 addresses
of any form (including [2001::6]:25565 ) and connecting to the server

BTW: I'm running windows 7 - 32bit

Today I installed the latest version of Java, and a new installation of Minecraft on two computers on
different networks.
The client PC could do "telnet 2001:6b0:1d:13::1:a834 25565" so I know the server answers on that address
(Client PC is 2001:6b0:1d:16::82a , a different subnet)

BUT in the game I still get "java.net.SocketException: Protocol family unavailable" when I
type 2001:6b0:1d:13::1:a834 in [Direct Connect]

There might have been another message flashing by, just before the java... error-message
(I caught "Connecting to server" by using PrintScreen, but there might have been more ?!?)

I have the same problem! I'm using MineCraft 1.5 "Direct Connect" and type "::1" (or 2001::6 or [2001::6] or [::1] )
Then I get java.net.SocketException: Protocol family unavailable

I do not have IPv6 connectivity to the internet, I'm only running it locally on my LAN...