[libvirt] IPv6 DNS and domain details

Hi all, I notice that the current IPv6 auto address implementation doesn't pass down any DNS details to the guest machine - which means that an 'IPv6 only' guest that works automatically is currently just out of reach. Support for handing out these details depends upon the version of 'radvd' that is installed on the host server. RHEL5's standard version has no support for DNS options. 6.0 has 1.6 installed which can hand out the DNS address, but you need 1.7 before DNS search lists from RFC6106 are supported. The data for these options is available in the network definition and it appears at first glance to be reasonably straightforward to add them. What do you think would be the best way to implement this? Is there a mechanism within libvirt already that checks versions of subsiduary programs and runs slightly different code accordingly? Or are there other plans in the pipeline? Rgs Neil Wilson