Depends on if your providing real I18N or not
The multilanguage support for this site is nothing more then putting much of the text into a seperate file indexed by language. That could be done just as easy afterwards as at the start. And the site doesn't include the code to actually switch text files based on language preferences nor does any of the rest of the code support it.
For one thing it uses a javascript popup menu which has a seperate configuration file that specifes the popup locations in pixels. Changing the text would throw it off completly.
A lof the HTML has implicit sizing assumptions that would likely break in another language. The tables for one follow what I mentioned in another item, with the headers in one table and the actual data in another. If you run into any data that excedes the size assumptions of the columns, the headers and data won't match up any more.
Real I18N support requires real planning, and this site certainly had little to none of that.
Jay