[Exim] defer senders segfaults

The new defer acl modifier doesn't like senders. Following in the
rcpt-acl causes Exim 4.11 to segfault.

defer senders = foo@???

(senders = : too and senders = some_kind_of_a_lookup as well)

Exim 4.11.

--
Kirill Miazine, Stud.Jur.                          mailto:sig@krot.org
Faculty of Law, University of Oslo                 http://km.krot.org/