link-local/Bonjour XMPP can't be contacted on Windows
With Gajim 0.16.1 on Windows 7, link-local/Bonjour XMPP can't be contacted. It seems to listen on [::]:5298 IPv6-only, but registers via Bonjour for IPv4 only. Connecting to the IP address and port via telnet locally does not work for IPv4, but works for IPv6. But the other host will try IPv4 only, so can't contact the Windows machine.
It seems there would be a flag missing when creating/binding the socket so that it will receive IPv4 connections, too. Otherwise, two sockets would need to be used, one for IPv6 only and one for IPv4 only.
(Besides, it would be nice if Gajim could register with Bonjour for IPv6, too, but this might be a problem on Apple's side.)
Steps to reproduce
Install Gajim on Windows 7 with Apple Bonjour printing services installed, start up and try to chat to the Windows machine from another machine on the network. It will try to connect via IPv4 and eventually time out. When chatting from the Windows machine to the other machine, the message is received and one can send answers to the Windows machine that will be received, too. But when trying initial contact anew from the other machine to the Windows machine, it will time out again.
OS version: Windows 7
GTK version: 2.24.10
PyGTK version: 2.24.0