Running fai-mirror I get this:
install:~# fai-mirror /var/fai-mirror/
Using configuration files from /etc/fai
Getting package information
bzip2: (stdin) is not a bzip2 file.
bzip2: (stdin) is not a bzip2 file.
Failed to fetch
http://www.informatik.uni-koeln.de/fai/download/dists/etch/koeln/binary-i386/Packages.bz2
Sub-process bzip2 returned an error code (2)
Failed to fetch
http://www.informatik.uni-koeln.de/fai/download/dists/etch/koeln/binary-i386/Packages.bz2
Sub-process bzip2 returned an error code (2)
...
Somethings broken here. Wil report if the packages are there anyway - at
least it looks fearsome to the attention-paying admin :)
Henning