commitfest app returning error 500

I just edited user 'alvarofherrera' in commitfest.pg.org to remove the
'active' flag, because that's some ancient test community account of
mine that somebody seems to have activated in commitfest.  However,
after doing that, the 'edit' interface of the patches that involve that
user now returns error 500:

https://commitfest.postgresql.org/29/2690/edit/
https://commitfest.postgresql.org/29/2673/edit/

I'm not familiar enough with Django to fix this ...

Of course, a workaround is to mark the user active, but since the
patches are both committed I don't think it's necessary.

-- 
Álvaro Herrera