kpackagekit sends error message

[jacques]

Binary package hint: kpackagekit

Kubuntu 10.04.1
kde 4.4.2

when trying to check sources, kpackagekit sends an "internal error" message

Error Type:
Error Value: coercing to Unicode: need string or buffer, exceptions.SystemError found
File : /usr/share/PackageKit/helpers/apt/aptBackend.py, line 2216, in
main()
File : /usr/share/PackageKit/helpers/apt/aptBackend.py, line 2213, in main
run(args, options.single)
File : /usr/share/PackageKit/helpers/apt/aptBackend.py, line 2175, in run
backend.dispatcher(args)
File : /usr/lib/python2.6/dist-packages/packagekit/backend.py, line 699, in dispatcher
self.dispatch_command(args[0], args[1:])
File : /usr/lib/python2.6/dist-packages/packagekit/backend.py, line 606, in dispatch_command
self.refresh_cache(force)
File : /usr/share/PackageKit/helpers/apt/aptBackend.py, line 202, in _locked_cache
func(*args, **kwargs)
File : /usr/share/PackageKit/helpers/apt/aptBackend.py, line 1498, in refresh_cache
format_string(error.message))
File : /usr/lib/python2.6/dist-packages/packagekit/backend.py, line 723, in format_string
txt = unicode(text, encoding, errors='replace')

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: kpackagekit 0.5.4-0ubuntu4.3
ProcVersionSignature: Ubuntu 2.6.32-24.43-generic-pae 2.6.32.15+drm33.5
Uname: Linux 2.6.32-24-generic-pae i686
Architecture: i386
Date: Wed Sep 22 08:52:44 2010
InstallationMedia: Kubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100427)
ProcEnviron:
 LANGUAGE=
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
SourcePackage: kpackagekit