software-properties-gtk crashed with ValueError in run(): <aptsources.sourceslist.SourceEntry object at 0x8c3b4cc> is not in list

[Gtmoraes1]

I was trying to change some PPA dist. to Natty, for usage.
Both Synaptic and Aptitude are installed. I've did change Oneiric to Natty once with success, before having both mentioned programs installed. Don't know if it's related.

ProblemType: Crash
DistroRelease: Ubuntu 11.10
Package: software-properties-gtk 0.81.9
ProcVersionSignature: Ubuntu 3.0.0-10.16-generic 3.0.4
Uname: Linux 3.0.0-10-generic i686
ApportVersion: 1.22.1-0ubuntu2
Architecture: i386
Date: Mon Sep 12 11:01:17 2011
ExecutablePath: /usr/bin/software-properties-gtk
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Beta i386 (20110901)
InterpreterPath: /usr/bin/python2.7
PackageArchitecture: all
ProcCmdline: /usr/bin/python /usr/bin/software-properties-hostnamek -n -t 0
PythonArgs: ['/usr/bin/software-properties-hostnamek', '-n', '-t', '0']
SourcePackage: software-properties
Title: software-properties-gtk crashed with ValueError in run(): <aptsources.sourceslist.SourceEntry object at 0x8c3b4cc> is not in list
UpgradeStatus: Upgraded to oneiric on 2011-09-12 (0 days ago)
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make Ubuntu better. This particular crash has already been reported and is a duplicate of bug #829286, 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.