janitor wont run; ERROR:dbus.proxies:Introspect error on :1.65

ERROR:dbus.proxies:Introspect error on :1.65:/: dbus.exceptions.DBusException: org.freedesktop.DBus.Error.AccessDenied: Rejected send message, 1 matched rules; type="method_call", sender=":1.69" (uid=0 pid=2744 comm="/usr/bin/python /usr/sbin/computer-janitor clean -") interface="org.freedesktop.DBus.Introspectable" member="Introspect" error name="(unset)" requested_reply="0" destination=":1.65" (uid=0 pid=2647 comm="/usr/bin/python /usr/share/computerjanitor/janitor")
ERROR:dbus.connection:Unable to set arguments ((),) according to signature None: <type 'exceptions.ValueError'>: D-Bus structs cannot be empty
Traceback (most recent call last):
  File "/usr/sbin/computer-janitor", line 35, in <module>
    main()
  File "/usr/share/computerjanitor/computerjanitorapp/cli/main.py", line 312, in main
    options.arguments.func(options.arguments)
  File "/usr/share/computerjanitor/computerjanitorapp/cli/main.py", line 293, in clean
    timeout=3600)
  File "/usr/lib/python2.7/dist-packages/dbus/proxies.py", line 135, in __call__
    **keywords)
  File "/usr/lib/python2.7/dist-packages/dbus/connection.py", line 566, in call_async
    message.append(signature=signature, *args)
ValueError: D-Bus structs cannot be empty

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: computer-janitor 2.1.0-0ubuntu6
ProcVersionSignature: Ubuntu 3.0.0-15.26-generic 3.0.13
Uname: Linux 3.0.0-15-generic i686
ApportVersion: 1.23-0ubuntu4
Architecture: i386
CheckboxSubmission: 3f05f4c2ad33795bd2ea179065fdea51
CheckboxSystem: efd05939b08abfe86caa44c3820f8e56
Date: Fri Apr 6 17:25:54 2012
EcryptfsInUse: Yes
InstallationMedia: Ubuntu-Netbook 10.10 "Maverick Meerkat" - Release i386 (20101007)
PackageArchitecture: all
SourcePackage: computer-janitor
UpgradeStatus: No upgrade log present (probably fresh install)