About the notion of "all languages": look at this citation:
It is usually estimated that the number of languages in the world varies between 3,000 and 8,000.
http://wiki.answers.com/Q/How_many_written_languages_are_in_the_world[^]This is only about
written language; apparently, you do not have consider all spoken ones.
I hope you understand that you need to translate each and every word in you UI in every language.
Go figure the size of your team. :-)
—SA