$ eix --installed mysql
[i] dev-db/mysql++
     Available versions:  
    (0)    2.2.2-r1 2.3.2
    (3)    (~)3.0.5 (~)3.0.9
     Installed versions:  3.0.9(3)(20:47:31 05.02.2012)
     Homepage:            http://tangentsoft.net/mysql++/
     Description:         C++ API interface to the MySQL database

[i] dev-db/mysql
     Available versions:  4.0.27-r1 4.1.22-r1 5.0.91 (~)5.0.92 5.1.51 (~)5.1.52 (~)5.1.52-r1 (~)5.1.53 5.1.56 (~)5.1.56-r1 (~)5.1.57 (~)5.1.58-r1 (~)5.1.59 5.1.61 (~)5.5.19 (~)5.5.20 {berkdb big-tables cluster +community debug embedded extraengine latin1 max-idx-128 minimal pbxt (+)perl profiling raid selinux ssl static systemtap test xtradb}
     Installed versions:  5.5.20(20:47:01 05.02.2012)(berkdb community perl ssl -cluster -debug -embedded -extraengine -latin1 -max-idx-128 -minimal -profiling -selinux -static -systemtap -test)
     Homepage:            http://www.mysql.com/
     Description:         A fast, multi-threaded, multi-user SQL database server.

[i] dev-db/mysql-init-scripts
     Available versions:  1.2 2.0_pre1-r2
     Installed versions:  2.0_pre1-r2(16:48:30 05.02.2012)
     Homepage:            http://www.gentoo.org/
     Description:         Gentoo MySQL init scripts.

[i] dev-db/mysql-workbench
     Available versions:  (~)5.2.34 5.2.35 (~)5.2.36 (~)5.2.37 {debug doc nls readline static-libs}
     Installed versions:  5.2.37(21:01:36 05.02.2012)(nls -debug -doc -static-libs)
     Homepage:            http://dev.mysql.com/workbench/
     Description:         MySQL Workbench

[i] dev-db/mysqltuner
     Available versions:  1.1.1 1.2.0
     Installed versions:  1.2.0(20:47:41 05.02.2012)
     Homepage:            http://www.mysqltuner.com
     Description:         MySQLTuner is a high-performance MySQL tuning script

[i] dev-perl/DBD-mysql
     Available versions:  4.01.7 (~)4.20.0 {embedded}
     Installed versions:  4.20.0(16:52:47 05.02.2012)(-embedded)
     Homepage:            http://search.cpan.org/dist/DBD-mysql/
     Description:         The Perl DBD:mysql Module

[i] dev-ruby/mysql2
     Available versions:  
    (0.2)    (~)0.2.7 (~)0.2.13 (~)0.2.17 (~)0.2.18
    (0.3)    (~)0.3.2 (~)0.3.6 (~)0.3.7 (~)0.3.11
    {elibc_FreeBSD ruby_targets_ree18 ruby_targets_ruby18 ruby_targets_ruby19 test}
     Installed versions:  0.3.11(0.3)(21:01:51 05.02.2012)(ruby_targets_ruby18 -elibc_FreeBSD -ruby_targets_ree18 -ruby_targets_ruby19 -test)
     Homepage:            https://github.com/brianmario/mysql2
     Description:         A modern, simple and very fast Mysql library for Ruby - binding to libmysql.

[i] dev-tcltk/mysqltcl
     Available versions:  *2.40 (~)2.50 3.05
     Installed versions:  3.05(20:47:38 05.02.2012)
     Homepage:            http://www.xdobry.de/mysqltcl/
     Description:         TCL MySQL Interface

[i] virtual/mysql
     Available versions:  4.0 4.1 5.0 5.1 (~)5.2 (~)5.3 (~)5.5 {embedded minimal static}
     Installed versions:  5.5(20:47:08 05.02.2012)(-embedded -minimal -static)
     Description:         Virtual for MySQL client or database

Found 9 matches.

$ cat /etc/make.conf
ACCEPT_KEYWORDS="~amd64"
CHOST="x86_64-pc-linux-gnu"
CFLAGS="-march=amdfam10 -O2 -pipe"
CXXFLAGS="${CFLAGS}"
MAKEOPTS="-j5"
CC=gcc
CXX=g++
AUTOCLEAN="yes"
PORTAGE_ELOG_CLASSES="warn error log qa"
PORTAGE_ELOG_SYSTEM="save"
FEATURES="parallel-fetch userfetch buildsyspkg candy metadata-transfer sandbox"
LINGUAS="ru en"
VIDEO_CARDS="nvidia" #nv vdpau  # vesa nouveau fbdev v4l
INPUT_DEVICES="evdev keyboard mouse"
ACCEPT_LICENSE="*"

EMERGE_DEFAULT_OPTS="--verbose --keep-going --jobs=1 --backtrack=30 --with-bdeps=y"

MMEDIA="alsa audio v4l v4l1 v4l2 v4l3 mpg123 vdpau mac mad vidix flac faac mp3 m3u mp4 xvid x264 aac dvd win32codecs gstreamer ffmpeg ogg vorbis matroska xvfb wav sip nv nvidia xv xvid real"

USE="unicode utf8 ${MMEDIA} \
     xinerama aware pear bash-completion zsh-completion -gdbm \
     opengl udev dbus locale jpeg jpeg2k gif tiff png svg python \
     zsh man-db real minizip hardened cleartype type1 nano  sqlite \
     ntfs fat ext4 e2fsprogs btrfs-progs reiserfsprogs reiser4progs ntfsprogs dosfstools \
     3dnowext 3dnow bash-completion xtables-addons iptables l7-protocols -bluetooth \
     -dirac -hal -ipv6 -httpd-php -phpmyadmin -apache2 -semantic-desktop -networkmanager \
     jfsutils app-misc/mc X acpi alsa -introspection"

XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip  \
                fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac \
               delude chaos account checksum dnetmap echo gradm"

NGINX_MODULES_HTTP="access auth_basic autoindex browser charset empty_gif fastcgi geo \
                    gzip limit_req limit_zone map memcached proxy referer rewrite scgi \
                    split_clients ssi upstream_ip_hash userid uwsgi addition cache_purge \
                    dav degradation flv geoip gzip_static headers_more image_filter \
                    perl push random_index realip secure_link slowfs_cache \
                    stub_status sub upload upload_progress xslt mp4"
NGINX_MODULES_MAIL="imap pop3 smtp"

PATCH_OVERLAY=/etc/portage/autopatch
GENTOO_MIRRORS="http://mirror2.corbina.ru/gentoo-distfiles/
                http://mirror.yandex.ru/gentoo-distfiles/
                http://gentoo.bloodhost.ru/"

# source /var/lib/layman/make.conf

QEMU_SOFTMMU_TARGETS="x86_64 arm i386"
QEMU_USER_TARGETS="arm i386 x86_64"

gentoo-laptop ~lupo # uname -a                                                                                        [gentoo-laptop][12:01]
Linux gentoo-laptop 3.2.2-funtoo-r0a #1 Thu Feb 2 21:40:28 FET 2012 i686 Genuine Intel(R) CPU T1350 @ 1.86GHz GenuineIntel GNU/Linux
gentoo-laptop ~lupo # eix -e mysql                                                                                    [gentoo-laptop][12:24]
[i] dev-db/mysql
     Available versions:  [M]4.0.27-r1 [M]4.1.22-r1 [M]5.0.91 [M](~)5.0.92 [M]5.1.51 [M](~)5.1.52 [M](~)5.1.52-r1 [M](~)5.1.53 5.1.56 (~)5.1.56-r1 (~)5.1.57 (~)5.1.58-r1 (~)5.1.59 (~)5.1.61 [M](~)5.5.19 [M](~)5.5.20 {berkdb big-tables cluster +community debug embedded extraengine latin1 max-idx-128 minimal pbxt (+)perl profiling raid selinux ssl static systemtap test xtradb}
     Installed versions:  5.1.61(23:57:51 31.01.2012)(berkdb community perl ssl -big-tables -cluster -debug -embedded -extraengine -latin1 -max-idx-128 -minimal -pbxt -profiling -selinux -static -test -xtradb)
     Homepage:            http://www.mysql.com/
     Description:         A fast, multi-threaded, multi-user SQL database server.

[i] virtual/mysql
     Available versions:  [M]4.0 [M]4.1 [M]5.0 5.1 [M](~)5.2 [M](~)5.3 [M](~)5.5 {embedded minimal static}
     Installed versions:  5.1(14:06:04 08.08.2011)(-embedded -minimal -static)
     Description:         Virtual for MySQL client or database

Found 2 matches.

gentoo-home lupo # uname -a                                                                                             [gentoo-home][12:26]
Linux gentoo-home 3.2.2-gentoo-r0a #1 SMP PREEMPT Mon Feb 6 06:49:30 FET 2012 x86_64 Pentium(R) Dual-Core CPU E6500 @ 2.93GHz GenuineIntel GNU/Linux
gentoo-home lupo # eix -e mysql                                                                                         [gentoo-home][12:26]
[u] dev-db/mysql
     Available versions:  [M]*3.23.58-r1[2] [M]4.0.27-r1 [M]4.0.27-r1[2] [M]4.1.22-r1 [M]4.1.22-r1[2] [M]5.0.54[2] [M]5.0.70-r1[2] [M](~)5.0.72[2] [M](~)5.0.72-r1[2] [M](~)5.0.76[2] [M](~)5.0.76-r1[2] [M](~)5.0.83[2] [M](~)5.0.84[2] [M]5.0.84-r1[2] [M](~)5.0.87[2] [M](~)5.0.88[2] [M](~)5.0.90[2] [M](~)5.0.90-r1[2] [M]5.0.90-r2[2] [M]5.0.91 [M]5.0.91[2] [M](~)5.0.91[3] [M](~)5.0.92 [M](~)5.1.39-r1[2] [M](~)5.1.44[2] [M](~)5.1.44-r1[2] [M](~)5.1.44-r2[2] [M](~)5.1.44-r3[2] [M](~)5.1.45[2] [M](~)5.1.45-r1[2] [M](~)5.1.46[2] [M](~)5.1.49[2] [M](~)5.1.49-r1[2] [M]5.1.50[2] [M]5.1.50-r1[2] [M](~)5.1.50-r2[3] [M](~)5.1.50-r3[3] [M]5.1.51 [M]5.1.51[2] [M](~)5.1.51[3] [M](~)5.1.51-r1[3] [M](~)5.1.52 [M](~)5.1.52[2] [M](~)5.1.52-r1 [M](~)5.1.52-r1[2] [M](~)5.1.52-r2[3] [M](~)5.1.53 [M](~)5.1.53[2] [M](~)5.1.53-r1[3] 5.1.56 (~)5.1.56-r1 (~)5.1.57 (~)5.1.58-r1 (~)5.1.59 5.1.61 (~)5.4.3_beta[1] (~)5.4.3_beta[2] [M](~)5.5.1_alpha_pre2[2] [M](~)5.5.1[1] [M](~)5.5.4_alpha_pre3[3] [M](~)5.5.19 [M](~)5.5.20 {berkdb big-tables cluster +community debug embedded extraengine innodb latin1 lib32 max-idx-128 minimal pbxt (+)perl profiling raid readline selinux ssl static systemtap tcpd test xtradb}
     Installed versions:  5.1.61(10:50:56 06.02.2012)(berkdb community perl ssl -big-tables -cluster -debug -embedded -extraengine -latin1 -max-idx-128 -minimal -pbxt -profiling -selinux -static -test -xtradb)
     Homepage:            http://www.mysql.com/
     Description:         A fast, multi-threaded, multi-user SQL database server.

[u] virtual/mysql
     Available versions:  [M]4.0 [M]4.0[2] [M]4.1 [M]4.1[2] [M]5.0 [M]5.0[2] [M](~)5.0[3] 5.1 5.1[2] (~)5.1[3] [M](~)5.2 [M](~)5.2[3] [M](~)5.3 (~)5.4[2] (~)5.4[3] [M](~)5.5 [M](~)5.5[2] [M](~)5.5[3] {embedded lib32 minimal static}
     Installed versions:  5.1(20:59:04 25.06.2011)(-embedded -minimal -static)
     Description:         Virtual for MySQL client or database

Found 2 matches.