The D-Bus spec calls for certain environment variables (such as DBUS_STARTER_ADDRESS and DBUS_START_BUS_TYPE) to be set when starting a service because a message was sent to it, see http://dbus.freedesktop.org/doc/dbus-specification.html#message-bus-starting-services It looks like systemd isn't setting these variables as it should.
If kdbus is used this is now correctly set.
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