The original source for Messages.properties can be found here: https://github.com/DSpace/DSpace/blob/master/dspace-api/src/main/resources/Messages.properties
For the Cocoon XML format: I will try to find someone to look at your code and finish this.
That's cool! We have some documentation for that at http://www.mediawiki.org/wiki/Help:Extension:Translate/File_format_support
Just a quick note that we haven't forgotten about this and will follow up in due course.
Nice! Some questions.
- Why you're not keeping English source and translations in the same repository? I don't know if fetching from one repo and committing to another is supported by our scripts (if Siebrand suggested that, ignore me).
- Can you use UTF-8 please?
- Several of those properties files are invalid. For instance  has a
\ufeffas first character.