Bug#308323: exim4-daemon-heavy: sometimes splits mail between alternative MXs for no good reason

[Steinar H. Gunderson]

Package: exim4-daemon-heavy
Version: 4.34-6
Severity: normal

We're currently running Exim on a quite bandwidth-constrained links, and
the following has become a problem lately, especially with aliases etc.
in the loop:

Sometimes, when an alias expands to multiple addresses that point to the
same domain (which has multiple MX records), Exim chooses to deliver
to half of the recipients via one MX and the other half to the other MX.
Thus, the message is sent out twice on the link, instead of simply
adding more RCPT records to the already existing connection. This
appears quite random to me; what should happen is that Exim decides MX
for a domain only once during delivery of a given message, instead of
forking into two processes delivering the same message.

-- System Information:
Debian Release: 3.1
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: i386 (i686)
Kernel: Linux 2.6.11.8
Locale: LANG=en_DK.UTF-8, LC_CTYPE=en_DK.UTF-8 (charmap=UTF-8)