Thank you.
After diggin a bit around I think i found the problem. The LC_ALL= was on de_DE.UTF-8 even after change the locale. After setting it manual with export LC_ALL=en_US.UTF-8 the checkout FTLDNS works.
The rest of the installation I will do later because at the moment I'm over VPN ssh on my system and don't want to risk stuck.
Will report then so...