Had the same problem.
that`s not chroot bug, it might be debootstrap.
Check your "/mnt/usb/etc/apt/sources .list", when using image and file protocol.
Instead of "deb file:/mnt/iso/ubuntu edgy main", you propably have "deb http://debootstrap.invalid edgy main"
Had the same problem. etc/apt/ sources .list", when using image and file protocol. iso/ubuntu edgy main", you propably have "deb http:// debootstrap. invalid edgy main"
that`s not chroot bug, it might be debootstrap.
Check your "/mnt/usb/
Instead of "deb file:/mnt/
debootstrap? forgets repository path, thats all .