I am not sure, if the german translation comes shipped in the package. Probably does. I have little knowledge about the project until now...

The german prios are: Blocker, Kritisch, Schwer, Unwesentlich, Trivial - what is all ok, besides 'Unwesentlich', which is not any better than 'Trivial' or even worse, meaning 'unsubstantial'. So to me as a tester and daily user I really have problems to work hard creating a JIRA and then being offered to mark it as 'being out of content'. That drives me nuts.