Since the server is in Germany, German law applies - neither BoP5's nor Frosty's version would suffice. Good news is: As long as it's not personenbezogene Information (information directly related to the person), and it does not reach the Sch?pfungsh?he (level of crativity) that is required for the Urheberrecht (German version of copyright laws) or is criminal, there's no basis for the user to ask for post removal.
You may want to have a look at:
http://www.law-vodcast.de/loschungsp...orum-mitglieds
(video in German)
All in all, asking for legal advice in the english forums as a German admin is not very advisable; anglosaxon laws in regards to privacy protection and copyright just differ too much.