Bug#409902: exim4: bad queue+retry handling on 4xx(greylisting)

[Simon Walter]

Package: exim4
Version: 4.63-10
Severity: normal

There is an interesting patch in the current exim-upstream version (4.64)
which fixes delay-problems if a mailserver returned a 4xx for a mailbox.
For a complet description of the problem, see below.

In my situation this causes sometimes huge delays for a single mailbox which
is quite annoying. I wonder if it's possible to backport this to debians exim version.

>From the exim ChangeLog:
Exim version 4.64
-----------------

PH/36 After a 4xx response to a RCPT error, that address was delayed (in queue
      runs only) independently of the message's sender address. This meant
      that, if the 4xx error was in fact related to the sender, a different
      message to the same recipient with a different sender could confuse
      things. In particualar, this can happen when sending to a greylisting
      server, but other circumstances could also provoke similar problems.
      I have changed the default so that the retry time for these errors is
      now
      based a combination of the sender and recipient addresses. This change
      can be overridden by setting address_retry_include_sender=false in the
      smtp transport.

Related discussion:
http://www.gossamer-threads.com/lists/exim/users/65173

-- Package-specific info:
Exim version 4.63 #1 built 05-Nov-2006 10:41:09
Copyright (c) University of Cambridge 2006
Berkeley DB: Sleepycat Software: Berkeley DB 4.3.29: (September  6, 2005)
Support for: crypteq iconv() IPv6 PAM Perl GnuTLS move_frozen_messages Content_Scanning Old_Demime
Lookups: lsearch wildlsearch nwildlsearch iplsearch cdb dbm dbmnz dnsdb dsearch ldap ldapdn ldapm mysql nis nis0 passwd pgsql
Authenticators: cram_md5 cyrus_sasl plaintext spa
Routers: accept dnslookup ipliteral iplookup manualroute queryprogram redirect
Transports: appendfile/maildir/mailstore/mbx autoreply lmtp pipe smtp
Fixed never_users: 0
Size of off_t: 8
Configuration file is /var/lib/exim4/config.autogenerated

-- System Information:
Debian Release: 4.0
  APT prefers testing
  APT policy: (500, 'testing'), (200, 'unstable')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.18.1
Locale: LANG=en_US, LC_CTYPE=en_US (charmap=ISO-8859-1)

Versions of packages exim4 depends on:
ii  debconf [debconf-2.0]         1.5.8      Debian configuration management sy
ii  exim4-base                    4.63-10    support files for all exim MTA (v4
ii  exim4-daemon-heavy            4.63-10    exim MTA (v4) daemon with extended

exim4 recommends no packages.

-- debconf information:
  exim4/drec: