Update: Mostly fixed, see this post.

Having trouble connecting my Dell M1330 running Ubuntu Ibex (64bit) to an ad-hoc network (tethering to an iPhone running PdaNet).

My M1330 has the Intel® PRO/Wireless 3945ABG wireless adapter, which (as of Ubuntu 8.04) uses the new iwl3945 kernel driver.

Googling showed that the iwl3945 driver, though it is hugely improved since 8.04, still has a few issues.

Symptoms:

Creating an ad-hoc networking using the NetworkManager applet appears to “time-out” after a very long time.

From the command-line, an ad-hoc network can be created successfully, ie, the following commands can be executed successfully:

 sudo ifconfig wlan0 down
 sudo iwconfig wlan0 mode ad-hoc
 sudo iwconfig wlan0 channel 4
 sudo ifconfig wlan0 up
 sudo iwconfig wlan0 essid "iPhoneTether"

After the above commands (creating the ad-hoc network), attempting to establish an IP in the network appears to “time-out” after a very long time, ie, the following commands time-out:

sudo dhclient wlan0
OR
sudo ifconfig wlan0 169.192.86.187

iwevent shows that when the iPhone connects to the ad-hoc network, “New Network” events fire continuously on the wlan0.

These events appear to block anything else from happening. Disconnect the iPhone and Ubuntu shortly jumps back to life, re-connect and Ubuntu bogs down again with infinite “New Network” events, hahah, kinda fun.