In order to use Internationalization and the acs-lang package you need to get dotlrn from CVS (see
https://openacs.org/projects/dotlrn/dotlrn-doc/dotlrn-installation). Using any dotlrn 1.X releases won't work, don't waste your time with that.
In the interest of sharing translations of the .LRN UI with everybody in the community we have been doing translations on the translation server at http://translate.dotlrn.collaboraid.net. I recommend that you do your translations there as well.
I've just now committed all new locales and UI translations from the translation server to CVS so that you can accss them on your local installations of .LRN.
Instructions about how to use I18N are at the translation server start page, in the APM if you click on a package and click Manage Internationalization, as well as in the I18N xml document in acs-core-docs.
Let me know if you have questions.
