/usr/bin/light-locker:6:_dbus_abort:_dbus_warn_check_failed:_dbus_warn_return_if_fail:dbus_message_new_method_call:gs_listener_send_switch_greeter

[errors.ubuntu.com bug bridge]

The Ubuntu Error Tracker has been receiving reports about a problem regarding light-locker. This problem was most recently seen with package version 1.8.0-1ubuntu1, the problem page at https://errors.ubuntu.com/problem/a7ba44bb4f9e6e6f0e1b82371832e33688a246ab contains more details, including versions of packages affected, stacktrace or traceback, and individual crash reports.
If you do not have access to the Ubuntu Error Tracker and are a software developer, you can request it at http://forms.canonical.com/reports/.