Turns out that this is actually a cdimage bug; it's installing the build system's syslinux on the images, which happens to be hardy. If you install a current syslinux instead, everything works as intended.
Turns out that this is actually a cdimage bug; it's installing the build system's syslinux on the images, which happens to be hardy. If you install a current syslinux instead, everything works as intended.