Asked my domain/name server provider about IPv6 support on Thursday. Got an answer today, consisting of a single link to their knowledge base article about php.ini. Get your act together, switchplus!
It seems more like the helpdesk person assigned to my case has no idea about what name servers or DNS are. Got a second knowledge base link now, about how I can set-up AAAA records. I have had those set-up since day 1, it's the name servers that give an error on ip6.nl/#!licit.li ...