You can find the file by name, iwaredir.ntf, which is called IBM iNotes Redirect.
I had to enable the show in advanced template list for the template for it to come up.
The first thing I got when replacing the template was this awesome language window!
Very cool, this did not come up when I replaced any other templates yet, so I will presume it is special to this db, but not unique I am sure as the only time. You can set the default here or in the properties box for the db afterwards.
I wonder if it reads your OS version and defines the language as my tests it only showed up in English. Or does it read the OS language default? I changed browser language and defaults and it didn't pick it up.
Usual click, ok, let it do it's thing.
Test it all out and go on your way.