do-release-upgrade crashed with AttributeError in distUpgrade(): 'SystemError' object has no attribute 'encode'

[rebel maroc]

an upgrade want to remove unity and some required files like Xorg-***

ProblemType: Crash
DistroRelease: Ubuntu 13.10
Package: ubuntu-release-upgrader-core 1:0.196
ProcVersionSignature: Ubuntu 3.10.0-2.9-generic 3.10.0
Uname: Linux 3.10.0-2-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.10.2-0ubuntu3
Architecture: amd64
CrashDB: ubuntu
Date: Thu Jul 4 17:56:37 2013
ExecutablePath: /usr/bin/do-release-upgrade
InstallationDate: Installed on 2013-06-24 (10 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Alpha amd64 (20130623)
InterpreterPath: /usr/bin/python3.3
MarkForUpload: True
PackageArchitecture: all
ProcCmdline: /usr/bin/python3 /usr/lib/ubuntu-release-upgrader/do-partial-upgrade --frontend=DistUpgradeViewGtk3
PythonArgs: ['/usr/bin/do-release-upgrade', '--frontend=DistUpgradeViewGtk3']
SourcePackage: ubuntu-release-upgrader
Title: do-release-upgrade crashed with AttributeError in distUpgrade(): 'SystemError' object has no attribute 'encode'
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make this software better. This particular crash has already been reported and is a duplicate of bug #1197889, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.