sudo does not work in live image in persistent mode

Binary package hint: sudo

Testing the maverick RC image (20100928.1) for edubuntu amd64 on VirtualBox.

When booting in the standard live image, 'sudo' and other commands requiring root work correctly.

When booting in 'persistent' mode on the same live image, 'sudo' returns:
ubuntu@ubuntu:~$ sudo ls
sudo: can't open /etc/sudoers: Permission denied
sudo: no valid sudoers sources found, quitting

This appears to affect other functionality as well. E.g. the shutdown button on the right side of the upper panel does not display a menu when clicked. When an ACPI power event is sent, the machine shuts down (cleanly) rather than prompting for shutdown/suspend/logout as it does in the non-persistent live image. Applications that use gksudo to run do not start when selected.

The persistent partition is ext2 and was cleanly formatted before using the live install.

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: sudo 1.7.2p7-1ubuntu2
ProcVersionSignature: Ubuntu 2.6.35-22.33-generic 2.6.35.4
Uname: Linux 2.6.35-22-generic x86_64
Architecture: amd64
Date: Tue Sep 28 15:41:07 2010
LiveMediaBuild: Edubuntu 10.10 "Maverick Meerkat" - Release Candidate amd64 (20100928.1)
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: sudo
Sudoers: Error: command ['gksu', '-D', 'Apport', '--', '/bin/cat', '/etc/sudoers'] failed with exit code 1:
VisudoCheck: Error: command ['gksu', '-D', 'Apport', '--', '/usr/sbin/visudo', '-c'] failed with exit code 1: