Comment 33 for bug 333730

The bug is easy to reproduce (at least under MacBookPro3,1) :
 1. boot and log in
 2. connect to wifi (I use WPA2)
 3. suspend
 4. resume
 5. now you are no more able to reconnect to wifi. It renders Ubuntu completely useless :-(

I confirmed that installing linux-backports-wireless-modules-karmic does not fixed the bug at all.

However, installing compat-wireless bleeding edge (as for 2009-11-07) seems to fix it. It also fix bug 278190, which I marked as duplicate as this one.

One should get compat-wireless from http://wireless.kernel.org/en/users/Download:

# downloaded http://wireless.kernel.org/download/compat-wireless-2.6/compat-wireless-2.6.tar.bz2 in /tmp
cd /tmp
tar -xf compat-wireless-2.6.tar.bz2
cd compat-wireless-*
./scripts/driver-select ath9k
make
make install
make unload
modprobe ath9k

Since jaunty, I do not use network manager anymore but wicd instead as recommended in comment 35 of bug 278190, so I did not try the solution cited by qos in bug 373680.