PowerDNS declared the Authoritative Server 3.x used by SoluteDNS End of Life back in December 2017. Since we integrated support for the 4.x branch we left the 3.x support Authoritative Server support in place. Per January 1st 2019 we will stop supporting the 3.x Authoritative Server in our solutions.
Up to January 1st 2019 we may no longer take into account the 3.x Authoritative Server branch for bug fixes, enhancements and new features. After January 1st 2019 we will gradually start removing support. If you are still using the 3.x branch please follow these instructions to upgrade to version 4.1 of the PowerNDS Authoritative Server.