ConsoleKit reports active/is-local only on the second+ login

Question

Running KDE Frameworks 5, Plasma 5, using sddm as a display manager.

ConsoleKit and PAM-linux are both installed.

Upon login (using the sddm login screen), ck-list-sessions returns FALSE for both is-local and active. Only one session is present.

If I log out, then back in, the two fields are both TRUE, as expected.

sddm is not a console-kit supporting dm. Therefore, I am using the pam_ck_connector.so module to attach a consolekit session.

The sddm startup file (/usr/share/sddm/scripts/Xsession) is modified to launch using the line:

eval exec "ck-launch-session dbus-lauch --exit-with-session $session"

The (I think relevant) pam files are as follows:

/etc/pam.d/sddm:

auth            include         system-auth
account         include         system-account
password        include         system-password
session         include         system-session
session         optional        pam_loginuid.so
session         optional        pam_ck_connector.so nox11
session         optional        pam_warn.so

/etc/pam.d/sddm-greeter:

# Load environment from /etc/environment and ~/.pam_environment
auth            required pam_env.so

# Always let the greeter start without authentication
auth            required pam_permit.so

# No action required for account management
account         required pam_permit.so

# Can't change password
password        required pam_deny.so

# Setup session
session         required pam_unix.so
#session        optional pam_loginuid.so
session         optional pam_ck_connector.so
session         optional pam_warn.so

pam_warn.so lines have been added to force logging to the /var/log/auth.log file. A typical login looks something like:

<date/time> <pc-name> sddm-helper: pam_unix(sddm-greeter:session): session opened for user sddm by (uid=0)
<date/time> <pc-name> sddm-helper: pam_warn(sddm-greeter:session): function=[pam_sm_open_session] flags=0 service=[sddm-greeter] terminal=[:0] user=[sddm] ruser=[<unknown>] rhost=[<unknown>] 
<date/time> <pc-name> sddm-helper: pam_unix(sddm:session): session opened for user <user-name> by (uid=0)
<date/time> <pc-name> sddm-helper: pam_ck_connector(sddm:session): nox11 mode, ignoring PAM_TTY :0
<date/time> <pc-name> sddm-helper: pam_warn(sddm:session): function= [pam_sm_open_session] flags=0 service=  [sddm] terminal=[:0] user=[<user-name>] ruser=[<unknown>] rhost=[<unknown>] 
<date/time> <pc-name> polkitd[810]: Registered Authentication Agent for unix-session:/org/freedesktop/ConsoleKit/Session4 (system bus name :1.38 [/opt/kde/lib64/libexec/polkit-kde-authentication-agent-1], object path /org/kde/PolicyKit1/AuthenticationAgent, locale en_GB.ISO-8859-1)

How can I make my system start normally the first time?