Version:           unspecified (using KDE 4.5.3) 
OS:                Linux

Hi there,
I hope I'm right here with my report. Today I've looked for Updates using KPackageKit, where I've got four Updates concerning language packages
-language-pack-de
-language-pack-de-base
-language-pack-en
-language-pack-en-base
-language-pack-de-base
I don't know if it plays any role. Afterwards I clicked the actualise-button. KPackageKit was searching and ended with:

unexpected error, please report this with these details (I translated the report from german, so the origin english text may differ, but the following is outputted by KPackageKit)

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')


Reproducible: Always

Steps to Reproduce:
restarting KPackageKit>Updates, then clicking the actualise-button

Actual Results:  
see details above

Expected Results:  
Running KPackageKit without any error/failure

all given