Comment 20 for bug 680444

I have similar symptoms ... running Kubuntu 11.04 64 bit on quad core.
Sometimes dbus maxes out a CPU when kmail is checking for mail, but other times it doesn't seem to be associated with kmail.

Sometimes, killing the dbus process that is using 100% of CPU causes screen to blank and keyboard to be unresponsive. In those cases, I could ssh in from another box, and shut down the machine.

Usually when dbus has maxed out a CPU, it is difficult to bring up a konsole terminal, and it times out instead of opening.