Actually it's not scheduled.
But CentOS already supports it and even shorewall does.
I'd start with something like this:
- install NethServer 7 (is coming, just hold on few hours)
- configure IPv6 by hand ( http://www.cyberciti.biz/faq/rhel-redhat-fedora-centos-ipv6-network-configuration/ )
- install shorewall6:
yum install shorewall6
- try to make it work