It took me some time, but now I have it up and running. My home network runs IPv6 and my server can be reached on an IPv6 address.
Unfortunately I don’t have a native IPv6 address and my provider (UPC/Chello) will not supply one. So I had to use a tunnel broker. After experimenting a bit I got stuck on the Tunnel Broker of Hurricane Electric.
My m0n0wall firewall supports the Tunnelbroker IPv6/IPv4 tunnels and after configuring some firewall rules everything is up and running.
Have to grab some screenshots and after that I’ll post how I did it.