In order to keep time properly, /etc/localtime must point to the correct time zone data file. Look around in /usr/share/zoneinfo/ and pick your timezone or a near-by big city.

# ln -sf /usr/share/zoneinfo/Europe/Berlin /etc/localtime
# date
Sun Feb 16 08:26:44 CET 2003

In most Gentoo Linux installations, your system clock is set to UTC (or GMT, Greenwhich Mean Time) and then your timezone is taken into account to determine the actual, local time. If, for some reason, you need your system clock not to be in UTC, you will need to edit /etc/rc.conf and change the value of CLOCK.

 recommended:
 CLOCK="UTC"
 or:
 CLOCK="local"

The next step is to set the LANG shell variable, which is used by your shell and window manager (and some other applications). Valid values can be found in /usr/share/locale and generally take the form ab_CD, where ab is your two letter language code and CD is your two letter country code. the _CD is left off if your language is only (or primarily) spoken in one country. LANG can be set in /etc/profile if you want it to take effect system-wide, or in ~/.bashrc as a user-specific setting.

 export LANG="de_DE@euro"

The keyboard layoud used by the console is set in /etc/rc.conf by the KEYMAP variable. Valid values can be found in /usr/share/keymaps/{arch}/. i386 has further subdivisions into layout (qwerty/, azerty/, etc.). Some languages have multiple options, so you may wish to experiment to decide which one fits your needs best.

 KEYMAP="de"
 KEYMAP="de-latin1"
 KEYMAP="de-latin1-nodeadkeys"

The keyboard layout to be used by the X server is specified in /etc/X11/XF86Config by the XkbLayout option.

 Section "InputDevice"
     Identifier  "Keyboard1"
     ...
     Option "XkbLayout"    "de"
     # Option XkbVariant"  "nodeadkeys"
     ...

In order to get your console to display the Euro symbol, you will need to set CONSOLEFONT in /etc/rc.conf to a file found in /usr/share/consolefonts/ (without the .psfu.gz). lat0-16 has the Euro symbol.

 CONSOLEFONT="lat0-16"

Getting the Euro symbol to work properly in X is a little bit tougher. The first thing you should do is change the fixed and variable definitions in /usr/X11R6/lib/X11/fonts/misc/fonts.alias to end in iso8859-15 instead of iso8859-1.

 fixed        -misc-fixed-medium-r-semicondensed--13-120-75-75-c-60-iso8859-15
 variable     -*-helvetica-bold-r-normal-*-*-120-*-*-*-*-iso8859-15

Some applications use their own font, and you will have to tell them separately to use a font with the Euro symbol. You can do this at a user-specific level in .Xdefaults (you can copy this file to /etc/skel/ for use by new users), or at a global level for any application with a resource file in /usr/X11R6/lib/X11/app-defaults/ (like xterm). In these files you generally have to change an existing line, rather than adding a new one. To change our xterm font, for instance:

 (in your home directory)
 $ echo 'XTerm*font: fixed' >> .Xresources 
 $ xrdb -merge .Xresources

To use the Euro symbol in (X)Emacs, add the following to .Xdefaults:

 Emacs.default.attributeFont: -*-courier-medium-r-*-*-*-120-*-*-*-*-iso8859-15

For XEmacs (not plain Emacs), you have to do a little more. In /home/user/.xemacs/init.el, add:

 (define-key global-map '(EuroSign) '[€])