Comment 20 for bug 520589

I believe I've had the same problem, but have done things differently and may have a work-around and possibly a clue:
* somehow nm-applet icon disappeared from the panel; both NetworkManager and nm-applet processes are running, but disappearance of the nm-applet icon disables human user control of networking in the GUI.
$ ps aux | grep NetworkM showed network manager daemon running
# kill -15 <NetworkManager_PID>
* immediate result was another instance of the NetworkManager daemon and appearance of the nm-applet icon in the panel
# shutdown -r now
* after system came up, nm-applet icon appears in the panel, per expectations; i.e. the system seems to have retained the state from the last shutdown.

Tho'ts: init kicks off NetworkManager and gdm stuff; gdm seems the parent of nm-applet. In the /etc/ tree the files for NetworkManager and gnome* show no recent timestamps, so no human and no process has overwritten any conf files. It seems there is some configuration issue at some low, possibly library, level (e.g. argument not properly passed).
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