Comment 21 for bug 308181

There are lots of issues related to caching and DNS, but I don't think that
necessarily should be a bottleneck to adding this support.

What you probably need to do is look at implementing this with a pref, and then
checking it in as off by default. You should also carefully research any
dependent changes to existing code, because you have to sell this to the module
owners.

After some bake time to make sure the existence of the feature is not causing
regressions, you can have individual users turn it on and see how it works.

Don't worry about caching now, it seems like the problems described w/ the
network load distributors would be issues for normal DNS as well.