tofu: Missing entry in the bindings table for new key

[Luis Ressel]

Hello,

I created a new key today. When I tried to verify a signature made by
this key, I got the error message

gpg: Signature made Sat Jan 21 01:07:59 2017 CET
gpg:                using RSA key DEADBEEF
gpg: Good signature from "foo <foo at example.org>" [ultimate]
gpg: aka "foo <foo at example.com>" [ultimate]
gpg: error updating TOFU database: NOT NULL constraint failed: signatures.binding
gpg: TOFU: error registering signature: General error

Apparently no entry for my key/userid had been recorded in the bindings
table. I was of course able to fix this by calling
"gpg --tofu-policy good DEADBEEF", but it still looks like a bug to me.
Any ideas how this could happen?

Potentially relevant facts:
* The new key's userid collides with that of my old key.
* I'm using the setting "tofu-default-policy unknown".

Regards,
Luis Ressel