LANGUAGE vs LANG

Hi,

I got this report about weird behaviour of locales:

After the fresh install of Sarge in Czech language you end up with
system where (almost) everything is localised to Czech and you can
read/write iso-8859-2 characters.

% cat /etc/environment
LANGUAGE="cs_CZ:cs:en_GB:en"
LANG=cs_CZ

Now the problem is when you switch the LANG to english, e.g.
export LANG=en_GB
(of course en_GB being generated with dpkg-reconfigure locales),
it still speaks in Czech, but iso-8859-2 specific characters are
messed, because en_GB of course uses iso-8859-1 charset.

You have to either unset LANGUAGE or remember to set it to the same
value as LANG (e.g. export LANGUAGE="en_GB").

The question is, what is this variable for?

In woody and before, where I had to setup the environment manually,
I didn't use LANGUAGE variable and everything was working ok.
man locale doesn't talk about this variable either.

Thanks for explanation
-- 
Miroslav Kure