NM 0.8.1 - DBus rejected messages

[Alex Buell <alex buell munted org uk>]

Every time I hang up on my mobile phone's GSM modem, I get the following in the logs:

Aug 18 15:12:09 lithium dbus-daemon: [system] Rejected send message, 1 matched rules; type="error", sender=":1.138" (uid=0 pid=32572 comm="/usr/sbin/NetworkManager) interface="(unset)" member="(unset)" error name="org.freedesktop.DBus.Error.UnknownMethod" requested_reply=0 destination=":1.170" (uid=0 pid=6063 comm="/usr/sbin/pppd))
Aug 18 15:12:09 lithium dbus-daemon: [system] Rejected send message, 1 matched rules; type="error", sender=":1.138" (uid=0 pid=32572 comm="/usr/sbin/NetworkManager) interface="(unset)" member="(unset)" error name="org.freedesktop.DBus.Error.UnknownMethod" requested_reply=0 destination=":1.170" (uid=0 pid=6063 comm="/usr/sbin/pppd))
Aug 18 15:12:09 lithium dbus-daemon: [system] Rejected send message, 1 matched rules; type="error", sender=":1.138" (uid=0 pid=32572 comm="/usr/sbin/NetworkManager) interface="(unset)" member="(unset)" error name="org.freedesktop.DBus.Error.UnknownMethod" requested_reply=0 destination=":1.170" (uid=0 pid=6063 comm="/usr/sbin/pppd))
Aug 18 15:12:09 lithium dbus-daemon: [system] Rejected send message, 1 matched rules; type="error", sender=":1.138" (uid=0 pid=32572 comm="/usr/sbin/NetworkManager) interface="(unset)" member="(unset)" error name="org.freedesktop.DBus.Error.UnknownMethod" requested_reply=0 destination=":1.170" (uid=0 pid=6063 comm="/usr/sbin/pppd))

This is with NetworkManager 0.8.1. Any idea what's causing this? 
-- 
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