This happened to me on a fresh install of Kubuntu 9.10. No updates possible through kpackagekit but still able to apply updates through aptitude. Noticed previous users had disappear with installing policykit-kde. No such package installed or available however there was one for just a policykit which I installed through aptitude and it resolved the kpackagekit and Policykit Authorization (in system settings) issues.
This happened to me on a fresh install of Kubuntu 9.10. No updates possible through kpackagekit but still able to apply updates through aptitude. Noticed previous users had disappear with installing policykit-kde. No such package installed or available however there was one for just a policykit which I installed through aptitude and it resolved the kpackagekit and Policykit Authorization (in system settings) issues.