Comment 12 for bug 456468

I had this issue in Lucid and the fix for me was to comment out the last line "iface eth0 inet dhcp" in /etc/network/interfaces and then reboot. After that the nm-applet started to manage the wired interface and this allowed the icon to be displayed. The way I found this was I miss the sound icon by a pixel and the hidden network manager icon said "Wired Network not managed".