The DNS CGI allows configuring up to two name servers. We should extend this to four or five because over time some people have asked for this. This should be an easy change.
Matthias sent in a patch: https://patchwork.ipfire.org/patch/1602/
Sorry, wrong bug. :-| If no one is against this, I will try and have a look at it.
Well, this is fixed by the new DNS CGI.