local-unbound in a jail

Afternoon all,

I suspect that I know the answer to this question, however... I have 
tried to run local-unbound in a jail (as I intend to run rspamd in said 
jail) but it seems like it doesn't play nicely because there's no 
loopback address *inside* the jail which is the only interface this 
service is designed to work with.

Trying to keep things minimal but I think I should be installing unbound 
or named from ports if I want a caching DNS server inside a jail, rather 
than abusing local-unbound?

Cheers,
Steve