DNS Resolver and ns in dmz

[pontus]

The DNS Resolver (unbound) fails to resolve domains who's NS is located on DMZ.
I've tried different configurations for Network Interfaces, Outgoing Network Interfaces and Enable Forwarding Mode to no avail.

The DNS-forwarder handles this without problems.

NAT-reflection is enabled for the 1:1 mapping of the ip used by the NS in the dmz, and one can query the NS directly from LAN.

What am I missing?