Trying to upgrade to 14.04 - Can't install 'kubuntu-desktop

[Lynn Wagner]

It was impossible to install a required package. Please report this as a bug using 'ubuntu-bug ubuntu-release-upgrader-core' in a terminal

Setting new software channels
Calculating changes

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: update-manager 1:0.156.14.17
ProcVersionSignature: Ubuntu 3.2.0-67.101-generic 3.2.60
Uname: Linux 3.2.0-67-generic x86_64
ApportVersion: 2.0.1-0ubuntu17.6
Architecture: amd64
Date: Thu Aug 14 11:13:59 2014
GsettingsChanges:
 com.ubuntu.update-manager first-run false
 com.ubuntu.update-manager launch-time 1408036328
 com.ubuntu.update-manager show-details true
 com.ubuntu.update-manager window-height 647
 com.ubuntu.update-manager window-width 600
InstallationMedia: Xubuntu 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120822.1)
MarkForUpload: True
PackageArchitecture: all
SourcePackage: update-manager
Symptom: ubuntu-release-upgrader-core
UpgradeStatus: Upgraded to precise on 2014-08-14 (0 days ago)
VarLogDistupgradeTermlog: