I have recently set up IPv6 prefix delegation on Comcast using Debian 7.4, and it works perfectly with the ISC DHCPv6 client, radvd and netfilter/ip6tables. The only problem is that I have multiple internal subnets on my firewall, and because the ISC DHCPv6 client only requests a single /64 prefix from the CMTS DHCPv6 server, I can only provision that prefix to one of my subnets using radvd.

I've done a lot of research online and can't find any definitive source indicating whether or not the ISC will add short prefix request support to their DHCPv6 client. Some of the other clients like Dibbler and WIDE do support it but I don't want to install another client and use that just for prefix delegation, especially since it will require me to make more mods to my network scripts.

Does anyone know if the ISC DHCPv6 client will ever add short prefix request support? Are there patches I can apply to the source to add this support?