[exim] heimdal_gssapi authenticator

Does anyone out there use the above? Build with it?

My initial attempts to build (having not found an obvious
fedora library package for heimdall, yet) are tripping over
a possibly incompatible /usr/include/krb5.h

There's also no testsuite coverage.

Finding out if there are actually any users would be
interesting. Perhaps it is moribund and should be withdrawn.
--
Cheers,
Jeremy