Karmic to Lucid dist-upgrade: hangs on kubuntu-/plasma-desktop

[bmw]

Already dist-upgraded on three other machines without a problem.
On a Dell D600 laptop, libplasmagenericshell4 will not install. I get the standard overwrite error.

Seems that this happens when trying to install either kubuntu-desktop and/or plasma-desktop.

Both Kde.pm and Gnome.pm files are missing.

Please advise.

unpacking libplasmagenericshell4 (from../libplasmagenericshell4_4%3a4.4.2-0ubuntu14_i386.deb) ...
dpkg: error processing /var/cache/apt/archives/libplasmagenericshell4_4%3a4.4.2-0ubuntu14_i386.deb (--unpack): 
 trying to overwrite '/usr/lib/libplasmagenericshell.so.4.4.0', which is also in package kdebase-workspace-bin 4:4.4.2-0ubuntu1~karmic~ppa4
Errors were encountered while processing:
 /var/cache/apt/archives/libplasmagenericshell4_4%3a4.4.2-0ubuntu14_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

Is this a repository listing problem in /etc/apt/sources.list ?
Should I uninstall kdebase-workspace-bin and let a fresh copy install in an empty space (prolly not recommended anyway)?

Please advise.