O Upstream adicionou um serviço separado ao expedidor. Tente executar:
systemctl enable NetworkManager-dispatcher.service
então
systemctl start NetworkManager-dispatcher.service
Como dbus-org.freedesktop.nm-dispatcher.service
é um alias, ele deve estar funcionando:
systemctl status dbus-org.freedesktop.nm-dispatcher.service
NetworkManager-dispatcher.service - Network Manager Script Dispatcher Service
Loaded: loaded (/usr/lib/systemd/system/NetworkManager-dispatcher.service; enabled)
Active: active (running) since Thu 2013-06-13 01:41:21 -0500; 3s ago
Main PID: 1569 (nm-dispatcher.a)
CGroup: name=systemd:/system/NetworkManager-dispatcher.service
└─1569 /usr/lib/networkmanager/nm-dispatcher.action