Languages in RSS feeds
Not sure I agree with Paschal. Filtering feeds by language is a technological problem. The solution should be technological, and should not impose a language on writers. If Ralf chooses to write in german, this is his choice.
Restricting yourself to reading posts in english (by choice or by lack of knowledge of the other languages) is a reader choice, not a publisher one.
RSS offers (or should offer) the possibility to define in what languages posts are written.