http://sn.1w6.org/file/mk-20140921T151529-qc77w8l.html
@mcscx I FOUND IT!!! For the whole new networking set up I had changed some IP adresses around - and apparently not rebooted since then. Turns out the /etc/network/interfaces file had the wrong gateway and primary DNS. (apparently I had adapted that IP address in the FRITZ comnfig though I can not remember that). Once I edited those, a domain name I was pinging 1)) resolved and 2) responded.