I've just created a repo with german translations for CodeIgniter.
This is built upon: http://mygengo.com/string/p/codeigniter-2-1/export/language/de/
Because there are a few lines missing I added them. For example 'show' & 'hide' on the profiler_lang.php...
I don't know where to submit this, but I'd like to contribute.
I'd usually tell you that you need to fork the repo, make your additions and submit a pull request, but I'm not sure if we would be able to support German after your initial contribution.
I have added my repo to this list, as german translation:
Correct, @narfbg, since we don't have any translators on staff to ensure accuracy, the official repo only supports English. @MetalMatze thanks for taking the time to do this, and for adding it to the language translation page, I'm sure many German speaking users will appreciate it.