nginx proxy fails using v6 hosts?

[Sven 'Darkman' Michels]

Hi,

me again, sorry.

I tried to use a internal v6 "only" host as proxy target, but i got this:
30279#0: *68 six.internal.tld could not be resolved (3: Host not found), client:
::ffff:x.x.x.x, server: dualstack.external.tld, request: "GET / HTTP/1.1", host:
"six.internal.dualstack.external.tld"

nginx was accessed via. v4 on the dual stack box. The resolver is specified in
the location, works for v4, on the box i can also resolve the v6, but nginx
cannot or at least the proxy module?

Regards,
Sven