Follow the link to find the instructions to convert Wheezy
to French,Spanish,German or Russian.
This is experimental. There might be problems with
drivers since the kernel is modified by the language package that
you install as a pet package. However it is stable and works
well in my testing .
The only flaw is a message at bootup time,
warning users of a 60 second pause.
Wheezy is modified to various languages.
Wheezy download page