Comment 23 for bug 330811

I can confirm that

'sudo iwlist wlan0 scan essid <hidden_ssid>'

works, and connects to the network. I had to do it twice (or maybe it was do it once and wait a little), but it worked. The network is then listed in the plasma widget and connected to automatically.

For people who are unsure what their wireless device is (wlan0 in my case), run 'ifconfig' to see the list of network devices. 'lo' is a loopback device, 'eth0' are network cards, etc.