Comment 10 for bug 1070647

Interesting, thank you again, now I see that network-manager spawns modem-manager trough D-bus.
But then what's /etc/init/modem-manager.conf meant for?
Without waiting an answer I've tried to remove it and things just seemed to get better.

As you suggested shutting down network-mamanger (which anyway takes whole 5 seconds to complete on my little eeepc) before shutdown made it as fast as it were with precise.

Tring to anticipate it's shutdown I've ended modifying both networking.conf and network-manager.conf to stop also on "runlevel [06]". I don't pretend this to be the solution but it helped somehow my shutdown to be faster and without unnecessary restarts of modem-manager.

Can it be that the stop of Network Manager is triggered to late in the chain, making services crash because network is already unavailable and then get started over and over?