Hi all, I just saw this:
http://www.kubuntu.org/node/110
which basically says KDE 4.2.4 has been moved from the PPA repos to the backports repos, with some extra fixes.
Since Gloria KDE pulled KDE 4.2.4 from the PPA repos you should now comment out the PPA repo and un-comment the backports repo, then update.
e.g. change the lines in /etc/apt/sources.list to:
deb http://archive.ubuntu.com/ubuntu/ jaunty-backports main restricted universe multiverse
#deb http://ppa.launchpad.net/kubuntu-ppa/backports/ubuntu jaunty main
Note the above 2 lines are not next to each other in the sources.list file.
but be careful with the update, watch what it wants to update.
All looked good for me, and got some good extra updates too.
Boo






