Problem was caused by there being no entry for "bookworm" in /usr/share/live/build/data/debian-cd. Fixed by
# cd /usr/share/live/build/data/debian-cd # ln -s squeeze bookworm This bug can now be closed. -- Ron Murray <r...@rjmx.net> PGP Fingerprint: 4D99 70E3 2317 334B 141E 7B63 12F7 E865 B5E2 E761