Well, it seems that on my machine the suggested setup on the carambola wiki didn't work.
As explained there, I tried virtual box and Xubunto which unfortunately failed twice,
so then I tried it on mac os x(getting all the packages from port , instead of with apt-get), which then also failed to compile.
As a last resort I tried Virtual Box + Ubuntu (not xubuntu) and I now finally succeeded in building openwrt!
I still have troubles integrating mysql, but I hope I can figure that one out today as well
BTW: for anybody who runs into trouble developing on a mac, here's what i did to finally make it work::
Mac os X 10.8.3 + Virtual box + Ubuntu 32 bit version
Then i got required packages as explained on
http://wiki.openwrt.org/doc/howto/buildroot.exigence (depends on OS version used in virtualbox)
PLUS the packages named on the carambola wiki under
http://8devices.com/wiki_carambola/doku ... e_to_startgit clone
https://github.com/8devices/carambola2 carambola2
cd carambola2
./scripts/feeds update -a
./scripts/feeds install -a
(install -a was apparently important - before I always only tried to install the pkgs that I really needed, which never worked)
make menuconfig
(-->select luci and the other required packages)
make
(wait 5 hours)
--> done