Comment 18 for bug 640689

I would guess (without reading the code) that it's trying to pass your real name, containing an eszett, to gpg, and this fails. Why are you trying to run it in LANG=C? In general doing anything with non-ascii data in that locale in Python is going to be quite problematic.

You could say perhaps quickly should at least give you a clean error, but that seems like a different bug...