I sent you this via e-mail, but I figured I'd update the thread so others would know:
Somehow you had an invalid/incompete (but disabled) config for RFC 2136 Dynamic DNS updates. The upgrade code for that was apparently very broken, and it caused the config upgrade to bomb/fail.
I fixed the upgrade code and on a test VM your config upgrades properly now.
Wait for the next snapshot or two and then give it another try.