Unbound ipset support

Unbound got IPSet support in the latest version.
I modified the make file and it compiled fine.
Modified my unbound.conf according to the unbound docs.
The log shows that the IPSet module got loaded.
It also shows some IPset function calls going on but no IPs get added into the IPSets.
Did someone else already tried this out and had a similar problem?
Also, it seems like there is only support for one IPSet? (1 for IPv4 and 1 for IPv6)