Bug#697612: exim4-daemon-light: "MAIN_LOCAL_DOMAINS=@:localhost" seems not to respect "@"

[Osamu Aoki]

Package: exim4-daemon-light
Version: 4.80-7
Severity: normal

loacl mails to root at localhost and osamu at localhost are delivered to local
without problem but local mails to root at goofy.localdomain and
osamu at goofy.localdomain are sent to smart host which is not what I expected
from the smarthost setting with debconf dialog:
 │ Please enter a semicolon-separated list of recipient domains for which    │  
 │ this machine should consider itself the final destination. These domains  │  
 │ are commonly called 'local domains'. The local hostname                   │  
 │ (goofy.localdomain) and 'localhost' are always added to the list given    │  
 │ here.

I naturally entered nothing there:
  dc_other_hostnames=''.                         (original)
in update-exim4.conf.conf via debconf.

I can work around this problem explicitly listing
  dc_other_hostnames='goofy.localdomain'         (workaround)
in update-exim4.conf.conf via debconf.  

But the above dialog and behavior does not make sense.

I checked /var/lib/exim4/config.autogenerated and saw 
MAIN_LOCAL_DOMAINS=@:localhost                    (original)
MAIN_LOCAL_DOMAINS=@:localhost:goofy.localdomain  (workaround)
which is correct result.  So "@" is not respected and I think there is
some bug around inside exim4 itself. 

(Does this comes from my stupidity of host configuration?)
Here is my host situation:
$ uname -n
goofy
$ hostname
goofy
$ hostname -f
goofy.localdomain
$ grep -v ^# /etc/hosts
127.0.0.1       localhost
127.0.1.1       goofy.localdomain       goofy

::1     localhost ip6-localhost ip6-loopback goofy.localdomain  goofy
fe00::0 ip6-localnet 
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

My router and ISP can handle IPv4/IPv6 as I understand.

-- Package-specific info:
Exim version 4.80 #3 built 02-Jan-2013 18:59:25
Copyright (c) University of Cambridge, 1995 - 2012
(c) The Exim Maintainers and contributors in ACKNOWLEDGMENTS file, 2007 - 2012
Berkeley DB: Berkeley DB 5.1.29: (October 25, 2011)
Support for: crypteq iconv() IPv6 GnuTLS move_frozen_messages DKIM
Lookups (built-in): lsearch wildlsearch nwildlsearch iplsearch cdb dbm dbmjz dbmnz dnsdb dsearch nis nis0 passwd
Authenticators: cram_md5 plaintext
Routers: accept dnslookup ipliteral manualroute queryprogram redirect
Transports: appendfile/maildir/mailstore autoreply lmtp pipe smtp
Fixed never_users: 0
Size of off_t: 8
Configuration file is /var/lib/exim4/config.autogenerated
# /etc/exim4/update-exim4.conf.conf
#
# Edit this file and /etc/mailname by hand and execute update-exim4.conf
# yourself or use 'dpkg-reconfigure exim4-config'
#
# Please note that this is _not_ a dpkg-conffile and that automatic changes
# to this file might happen. The code handling this will honor your local
# changes, so this is usually fine, but will break local schemes that mess
# around with multiple versions of the file.
#
# update-exim4.conf uses this file to determine variable values to generate
# exim configuration macros for the configuration file.
#
# Most settings found in here do have corresponding questions in the
# Debconf configuration, but not all of them.
#
# This is a Debian specific file

dc_eximconfig_configtype='smarthost'
dc_other_hostnames=''
dc_local_interfaces='127.0.0.1 ; ::1'
dc_readhost='debian.org'
dc_relay_domains=''
dc_minimaldns='false'
dc_relay_nets=''
dc_smarthost='smtp.nifty.com::587'
CFILEMODE='644'
dc_use_split_config='true'
dc_hide_mailname='false'
dc_mailname_in_oh='true'
dc_localdelivery='mail_spool'
mailname:goofy.localdomain

-- System Information:
Debian Release: 7.0
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (10, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.7-trunk-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_US.utf8, LC_CTYPE=en_US.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages exim4-daemon-light depends on:
ii  debconf [debconf-2.0]  1.5.49
ii  exim4-base             4.80-7
ii  libc6                  2.13-38
ii  libdb5.1               5.1.29-5
ii  libgnutls26            2.12.20-3
ii  libpcre3               1:8.31-2

exim4-daemon-light recommends no packages.

exim4-daemon-light suggests no packages.

-- debconf information:
  exim4-daemon-light/drec: