The problem is that KVM can't read your cd-rom, the dahdi error it's just a consequence of that. I had similar problems with virtualbox, I fixed them just unmounting the CD-ROM from the virtualbox interface before booting the second phase of the installation, and then mounting it again after eBox installer prompt me to do it. I don't know if you can do something similar with that KVM.
Hope this helps!
Regards,
J. A. Calvo