Roll forward over the last revision's backout.
This reinstates exim-4.21, but with PORTREVISION bumped so that folks
unlucky enough to get the bum version can easily upgrade.
Include a patch to fix the reported IPv6 bug.
Revert previous delta, which updated to exim-4.21.
The update causes segfaults during remote delivery for at least one
IPv6 user, and I don't have an IPv6 testbed to work with yet.
Requested by: Suresh Ramasubramanian <email@example.com>
Update to exim-4.21:
* This is a mostly maintenance release, although some new features have
been added (including Sieve support).
The non-ACL exiscan patch is no longer supported. The exiscan-acl patch
is now used by default, unless WITHOUT_EXISCAN is given.
This means that existing installations that rely on non-ACL exiscan
CAN NOT be upgraded without changes to the configure file.