Googling around using the rebuildd keyword to find if people were talking about it, I found that patch from Ubuntu.

This patch is used to ship rebuildd Debian package in Ubuntu.

Wahou. First surprise! So, Ubuntu is fixing bugs and not telling me. I though that people saying "Ubuntu does not contribute back to Debian!" were exaggerating. Seems I was wrong.

Nevermind: I take the patch. I read the patch. I apply the pat… oh wait: the fix is wrong.

lol.