According to ftp://ftp.mrunix.net/pub/webalizer/INSTALL , you must specify the language when you compile Webalizer from the sources.
You must compile Webalizer from the sources and specify your language then. You cannot use Debian's Webalizer package if you need a language other than English.
Debian webalizer uses gettext, so it will generate statistics on the default locale of your system. With Debian > 4.0 (etch), you can change your locale with: update-locale LANG=es_ES.UTF-8 You can momentarily force generation in another language simply changing your LANG: export LANG=es_ES.UTF-8; webalizer More info: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=291368