My underlying expectation here is that the admin should get email when
there is a bug in Roundup or the instance code, but not simply for
attempts to access the instance by a client on a bad connection, or by a
misbehaving client.  (There are lots of robots and other clients out
there doing things that a proper browser implementation of HTTP, on a
good connection, following valid links and making valid form submissions
only, would never do, and so there can be unhelpfully many such emails
when a robot does the same problematic thing on many pages.  I have a
few other Roundup backtraces to investigate that may also relate to
clients doing dubious things.)

I do happen to have an unsubmitted local patch to increase the default
timeout from a hardcoded 60 seconds to a hardcoded 300 seconds
(essentially an attempt to reduce the frequency of the errors in the
present issue from before I wrote the patch attached to this issue, I
think).