Text::Language::Guess guesses a document's language. Its implementation
is simple: Using "Text::ExtractWords" and "Lingua::StopWords" from CPAN,
it determines how many of the known stopwords the document contains for
each language supported by "Lingua::StopWords".

Each word in the document recognized as stopword of a particular
language scores one point for this language.

The "language_guess()" function takes a document as a parameter and
returns the abbreviation of the language that it is most likely written
in.

WWW: http://search.cpan.org/dist/Text-Language-Guess/