package kdm (not installed) failed to install/upgrade: subprocess installed post-removal script returned error exit status 1

[Johan]

Binary package hint: kdebase-workspace

I did a installation of kubuntu with ubuntu installed. when I wanted to go back kdm failed to uninstall

ProblemType: Package
DistroRelease: Ubuntu 10.10
Package: kdm (not installed)
ProcVersionSignature: Ubuntu 2.6.35-22.35-generic 2.6.35.4
Uname: Linux 2.6.35-22-generic x86_64
NonfreeKernelModules: nvidia wl
AptOrdering: kdm: Purge
Architecture: amd64
Date: Thu Oct 21 18:20:32 2010
ErrorMessage: subprocess installed post-removal script returned error exit status 1
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
SourcePackage: kdebase-workspace
Title: package kdm (not installed) failed to install/upgrade: subprocess installed post-removal script returned error exit status 1