I have fresh Kubuntu 7.10 installation, and I have also the problem when unlocking. The most strange thing is, I have no problem with that on a second PC - it just works. The workaround can be found in ubuntuforums.org:
sudo chmod 4755 /usr/bin/kcheckpass
Still it is not clear why it's working on a second PC, the permissions there are 755.
I have fresh Kubuntu 7.10 installation, and I have also the problem when unlocking. The most strange thing is, I have no problem with that on a second PC - it just works. The workaround can be found in ubuntuforums.org:
sudo chmod 4755 /usr/bin/kcheckpass
Still it is not clear why it's working on a second PC, the permissions there are 755.