Downgrading exim4 from 4.80 to 4.77 fixes this problem. I do not know whether this is due to a bug in gnome-keyring or a bug in exim4. I leave it to the maintainers of those packages to decide and reassign this bug if necessary.
-- Michael Welsh Duggan (m...@md5i.com) -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org