When I tried to update my version of Kubuntu 11.10, (~125 packages) every time a update package tried to install, a prompt window kept opening saying "This package is unsigned and could potentially damage your computer". This pattern repeated for all the update packages, so fearing I would have to click the prompt 125 times, I ended up using sudo-apt get update and sudo-apt get upgrade on the CLI to update my Kubuntu system (this is the workaround for those who end up with this error). Not only is this an annoyance, if there are a large amount of packages, it could take much longer than necessary to update the system. This is a serious bug that needs to be fixed.