Update to version 9.10.3-P4 of the Bind DNS server. This package was build on a Slackware 13.x system, but appears to work equally well on Slackware 14.x x64. You will also need the idnkit package (was needed to build the Bind package anyway).
For Slackware 13.x and 14.x x64:
Enjoy 🙂