Bugzilla Bug 175236

In my LINGUAS I have "es" and "es-ES", not "es-AR":
[ebuild   R   ] mail-client/mozilla-thunderbird-2.0.0.0  USE="gnome ipv6 ldap
-bindist -crypt -debug -mozdom -moznopango -replytolist -xinerama -xprint"
LINGUAS="es es_ES -be -bg -ca -cs -da -de -el -en -en_GB -es_AR -eu -fi -fr -ga
-ga_IE -hu -it -ja -lt -mk -nb -nb_NO -nl -pa -pa_IN -pl -pt -pt_BR -pt_PT -ru
-sk -sl -sv -sv_SE -tr -zh -zh_CN -zh_TW" 0 kB 

But it defaults to es-AR language:
LOG: unpack
Selected language packs (first will be default): es-AR es-ES en

WARN: install
Installing includes and idl files...

LOG: install
Selected language packs (first will be default): es-AR es-ES en

LOG: preinst
Removing old installs though some really ugly code.  It potentially
eliminates any problems during the install, however suggestions to
replace this are highly welcome.  Send comments and suggestions to
mozilla@gentoo.org

My emerge --info:
Portage 2.1.2.2 (default-linux/x86/2006.1, gcc-4.1.1, glibc-2.5-r0, 2.6.20-ck1
i686)
=================================================================
System uname: 2.6.20-ck1 i686 Genuine Intel(R) CPU           T2300  @ 1.66GHz
Gentoo Base System release 1.12.9
Timestamp of tree: Thu, 19 Apr 2007 07:20:01 +0000
ccache version 2.4 [enabled]
dev-java/java-config: 1.3.7, 2.0.31-r5
dev-lang/python:     2.4.3-r4
dev-python/pycrypto: 2.0.1-r5
dev-util/ccache:     2.4-r6
sys-apps/sandbox:    1.2.17
sys-devel/autoconf:  2.13, 2.61
sys-devel/automake:  1.4_p6, 1.5, 1.6.3, 1.7.9-r1, 1.8.5-r3, 1.9.6-r2, 1.10
sys-devel/binutils:  2.16.1-r3
sys-devel/gcc-config: 1.3.15-r1
sys-devel/libtool:   1.5.22
virtual/os-headers:  2.6.17-r2
ACCEPT_KEYWORDS="x86"
AUTOCLEAN="yes"
CBUILD="i686-pc-linux-gnu"
CFLAGS="-O2 -pipe -fomit-frame-pointer -march=pentium-m -mfpmath=sse -msse3"
CHOST="i686-pc-linux-gnu"
CONFIG_PROTECT="/etc /usr/kde/3.5/env /usr/kde/3.5/share/config
/usr/kde/3.5/shutdown /usr/share/X11/xkb /usr/share/config"
CONFIG_PROTECT_MASK="/etc/env.d /etc/env.d/java/ /etc/gconf
/etc/java-config/vms/ /etc/revdep-rebuild /etc/splash /etc/terminfo
/etc/texmf/web2c"
CXXFLAGS="-O2 -pipe -fomit-frame-pointer -march=pentium-m -mfpmath=sse -msse3"
DISTDIR="/usr/portage/distfiles"
FEATURES="ccache distlocks fixpackages metadata-transfer parallel-fetch sandbox
sfperms strict"
GENTOO_MIRRORS="http://mirror.ovh.net/gentoo-distfiles/ "
LANG="es_ES.UTF-8"
LC_ALL="es_ES.UTF-8"
LINGUAS="es es_ES en_US"
MAKEOPTS="-j3"
PKGDIR="/usr/portage/packages"
PORTAGE_RSYNC_EXTRA_OPTS="--exclude-from=/etc/portage/rsync_excludes"
PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --compress
--force --whole-file --delete --delete-after --stats --timeout=180
--exclude=/distfiles --exclude=/local --exclude=/packages
--filter=H_**/files/digest-*"
PORTAGE_TMPDIR="/var/tmp"
PORTDIR="/usr/portage"
PORTDIR_OVERLAY="/usr/portage/local/layman/armagetron
/usr/portage/local/layman/sunrise /usr/local/portage"
SYNC="rsync://rsync.europe.gentoo.org/gentoo-portage"
USE="X a52 aac acl acpi aim alsa arts asf audiofile avi bash-completion bcmath
beagle bidi bitmap-fonts bonobo bzip2 bzlib cairo caps cdb cddb cdparanoia cdr
cdrparanoia cli cpdflib cracklib cross crypt css cups curl curlwrappers dbus
divx4linux dri dts dv dvb dvd dvdr dvdread emerald encode escreen esd exif fam
fbcon ffmpeg firefox flac foomaticdb fortran ftp galago gb gcj gd gif gimp
gimpprint glitz glut glx gmp gnome gphoto2 gpm gstreamer gtk gtk2 gtkhtml guile
hal iconv imagemagick imlib ipv6 isdnlog jabber jack java jikes jpeg kde
kdeenablefinal kdehiddenvisibility latex lcms ldap lesstif libg++ libnotify
logrotate mad mbox midi mikmod mime ming mmap mmx mmxext mng modplug mono motif
mp3 mpeg mpi mplayer musepack musicbrainz nas ncurses nethack nls nocd nptl
nptlonly nsplugin ntfs nvidia ogg oggvorbis openal opengl opnegl pam pcmcia
pcre pdf pdflib perl pic png pnp posix ppds pppd python qt qt3 qt4 quicktime
readline real reflection reiserfs rpm rtc ruby scanner sdl seamonkey session
slang slp smp sndfile sockets socks5 speex spell spl sse sse2 sse3 ssl
startup-notification svg syslog tcltk tcpd tetex tga theora threads tiff
timidity tk truetype truetype-fonts trusted type1-fonts unicode usb userlocales
v4l v4l2 vcd videos vim vorbis wifi win32codecs wma wmf wxwindows x86
xcomposite xine xml xorg xpm xv xvid zlib" ALSA_CARDS="ali5451 als4000 atiixp
atiixp-modem bt87x ca0106 cmipci emu10k1 emu10k1x ens1370 ens1371 es1938 es1968
fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx
via82xx-modem ymfpci" ALSA_PCM_PLUGINS="adpcm alaw asym copy dmix dshare dsnoop
empty extplug file hooks iec958 ioplug ladspa lfloat linear meter mulaw multi
null plug rate route share shm softvol" DVB_CARDS="usb-dib0700 bcm3510
dibusb-usb1 dibusb-usb2 nxt2002 nxt200x or51132 or51211 sp8870 sp887x tda1004x
ttpci ttusb-dec usb-a800 usb-bluebird usb-dtt200u usb-umt usb-vp702x usb-vp7045
usb-wt220u" ELIBC="glibc" INPUT_DEVICES="keyboard mouse synaptics"
KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001
mtxorb ncurses text" LINGUAS="es es_ES en_US" USERLAND="GNU"
VIDEO_CARDS="nvidia nv vesa fbdev"
Unset:  CTARGET, EMERGE_DEFAULT_OPTS, INSTALL_MASK, LDFLAGS, PORTAGE_COMPRESS,
PORTAGE_COMPRESS_FLAGS


Reproducible: Always

Should be fixed now.

Thanks for reporting.