http/ftp://gd.tuwien.ac.at shows up in the mirror selection of the
actual install media, but is not listed in the mirrorlist and
mirror-status pages, in fact, those two pages do not show any mirror in
Austria at all (Austria does not even show up in the country selection
box on mirrorlist).
I recently checked the repos on ftp://gd.tuwien.ac.at, Arch is listed
as distro there, and the lastsync file shows an actual date, but I am
not sure if all the packages are really up-to-date and if it is ok to
use that mirror or not.
Greetings from Austria,