I installed the Raring network-manager package (0.9.7.995+git201301311547.17123fc-0ubuntu1) in my Quantal install, and the bug seems gone.
Now I just have this displayed at shutdown :
nm-dispatcher.action: Caught signal 15, shutting down...
Rather than invoking init scripts through /etc/init.d, use the service utility ..........
... blabla...
I installed the Raring network-manager package (0.9.7. 995+git20130131 1547.17123fc- 0ubuntu1) in my Quantal install, and the bug seems gone.
Now I just have this displayed at shutdown :
nm-dispatcher. action: Caught signal 15, shutting down...
Rather than invoking init scripts through /etc/init.d, use the service utility ..........
... blabla...
But it's just a warning.