I have actually just posted some input to the bug Bug #67546, which is a duplicate bug of this one.

Ok, I repeat what I posted there:

--------------- snip ------------
I can confirm this bug. I tried to install from the Ubuntu Edgy RC Live CD, but my network card would not get detected. The live cd even froze on me later during installation (during the "Installing software" part).

Ok, I downloaded the RC alternate CD. During the installation procedure, three network interfaces were detected. wifi0, ath0 and eth0. Well, I have only two cards, the Atheros-based Wifi (ath0) card and the Ethernet card (eth0). Selecting either wifi0 or ath0 did not allow me to connect to my network which is completely open. Only eth0 worked. Ok, again the installer chocked during the "software installation" part, put at least I could finish the installation and reboot. I was thrown to the command prompt though. Ok, I manually added the repositories to /etc/apt/sources.list and did a apt-get update followed by apt-get install kubuntu-desktop. I could download everthing via the ethernet connection from the Ubuntu servers. After finishing, I rebootet my computer and everything worked, apart, alas, wifi was and still is not working.

Here is the output of lspci (only the network controllers shown):
 00:0a.0 Ethernet controller: Atheros Communications, Inc. AR5212 802.11abg NIC (rev 01)
 00:0f.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ (rev 10)

As you can see, I have the same chip as the original bug reporter of the duplicate bug  #67546.

The modules are loaded:
 $ lsmod | grep ath
 ath_pci 100000 0
 ath_rate_sample 16512 1 ath_pci
 wlan 207580 4 wlan_scan_sta,ath_pci,ath_rate_sample
 ath_hal 192976 3 ath_pci,ath_rate_sample

Output of ifconfing:
 $ ifconfig
 ath0 Link encap:Ethernet HWaddr 00:0F:A2:30:C4:AC
           inet6 addr: fe80::20f:a3ff:fe40:c4ac/64 Scope:Link
           UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
           RX packets:0 errors:0 dropped:0 overruns:0 frame:0
           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:0
           RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
eth0 Link encap:Ethernet HWaddr 00:30:1B:3D:97:E8
           inet addr:192.168.123.103 Bcast:192.168.123.255 Mask:255.255.255.0
           inet6 addr: fe80::230:1bff:fe3d:97e8/64 Scope:Link
           UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
           RX packets:68650 errors:0 dropped:0 overruns:0 frame:0
           TX packets:40490 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:1000
           RX bytes:94239289 (89.8 MiB) TX bytes:3246866 (3.0 MiB)
           Interrupt:209 Base address:0xc000
lo Link encap:Local Loopback
           inet addr:127.0.0.1 Mask:255.0.0.0
           inet6 addr: ::1/128 Scope:Host
           UP LOOPBACK RUNNING MTU:16436 Metric:1
           RX packets:0 errors:0 dropped:0 overruns:0 frame:0
           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:0
           RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
wifi0 Link encap:UNSPEC HWaddr 00-0F-A2-30-C4-AC-00-00-00-00-00-00-00-00-00-00
           UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
           RX packets:96183 errors:0 dropped:0 overruns:0 frame:95
           TX packets:3222 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:199
           RX bytes:7504609 (7.1 MiB) TX bytes:148205 (144.7 KiB)
           Interrupt:217 Memory:f8b40000-f8b50000

Output of iwconfig:
$ iwconfig
 lo no wireless extensions.
eth0 no wireless extensions.
wifi0 no wireless extensions.
ath0 IEEE 802.11g ESSID:""
           Mode:Managed Frequency:2.437 GHz Access Point: Not-Associated
           Bit Rate:0 kb/s Tx-Power:16 dBm Sensitivity=0/3
           Retry:off RTS thr:off Fragment thr:off
           Power Management:off
           Link Quality=0/94 Signal level=-95 dBm Noise level=-95 dBm
           Rx invalid nwid:95411 Rx invalid crypt:0 Rx invalid frag:0
           Tx excessive retries:0 Invalid misc:0 Missed beacon:0
sit0 no wireless extensions.

I tried everyting from manually bringing up the network and also by using knetworkmanager. Unfortunately, nothing succeeded.
-------------- snap ------------

I have also installed linux-generic (dpkg -l gives me):
ii  linux-restrict 2.6.17.5-11 

I rebooted the computer just to be sure. Still, Wifi would not work. Funny is, that I can see my network in the Knetworkmanager popup window, but I cannot connect to it.