Bug#620036: live-magic: Refers to lenny as stable and squeeze as testing
It's not an update issue. It is because the code-names, Lenny &
Squeeze were the correct ones before Squeeze became stable and they
have forgotten to change it right before its release.
The program actually uses code names (i.e. squeeze & lenny) and not
testing & stable. Take a look at file bootstrap in the build
directory, lines 27-29:
# $LB_DISTRIBUTION: select distribution to use
# (Default: lenny)
If you want to create a stable Debian live CD use "testing (squeeze)"
until the bug is fixed.