OpenWRT: accepting Router Adverts from the ISP in White Russian?

As we are getting closer to the World IPv6 Day, I thought that I'd see if I can upgrade my WRT54GL's OpenWRT (White Russian) installation to accept Router Adverts from the ISP to acquire an IPv6 address (rather than via a 4-to-6 tunnel broker, which seems to be the most documented case), and to propagate its IPv6 address space to my local network via my WRT45GL's radvd. Unfortunately, most of the instructions out there concern newer OpenWRT releases to which I cannot upgrade to because their software base takes up significantly more space than White Russian does. Still, I figure that someone in the community must have already succeeded at configuring their WRT54GL for this and might be able to help. Anyone? :)