We spend some hours by solving this issue on fresh edgy installation.
If try launching nm-applet with
nm-applet --sm-disable ``` doesn't work, then here is the soloution. Change in the following two files:
- /etc/dbus-1/system.d/NetworkManager.conf
- /etc/dbus-1/system.d/nm-applet.conf
<policy context="default">
<allow own="org.freedesktop.NetworkManager"/>
<allow send_destination="org.freedesktop.NetworkManager"/>
<allow send_interface="org.freedesktop.NetworkManager"/>
</policy>
```
To:
<policy context="default">
<allow own="org.freedesktop.NetworkManager"/>
<allow send_destination="org.freedesktop.NetworkManager"/>
<allow send_interface="org.freedesktop.NetworkManager"/>
</policy>
```
Then restart dbus:
sudo /etc/init.d/dbus restart
```
And launch the applet:
nm-applet
```
Now it should work like a charm.