wireless Extensions version is incompatible with wireless-tools compiled in the kernel
There is a version incompatibility between the Wireless-tools and
Wireless Extensions packages compiled in the current kernel of Ubuntu
(7.10) (possibly this problem has been carried over to Hardy Herron
(8.04)? It was there already in Feisty Fawn (7.04) but in Dapper Drake
(6.10) the versions were compatible.
On my laptop I have Ubuntu 7.10 (kernel: 2.6.22-14-386) installed and
get the following output from iwconfig:
iwconfig Wireless-Tools version 29
Compatible with Wireless Extension v11 to v21.
Kernel Currently compiled with Wireless Extension v22.
ath0 Recommend Wireless Extension v13 or later,
Currently compiled with Wireless Extension v22.
I.e. The kernel should have been compiled with version v21 of Wireless
Extensions (not v22).
This prevents network manager from connecting to hidden access points
and may cause other problems.