Help with notebook wi-fi

[Robert O. Kahl]

I'm unable to get wifi working on my Presario Laptop (H-P) Model 
V6719NR.  Any Help would be appreciated.
The system is setup with Fedora 8/KDE, dual boot with Vista  The 
start-up error message shows:

Bringing up interface for wlan0.   Error for wireless request "Set Mode" 
(8B06)
SET failed on device  wlan0;     invalid argument
Determining IP info for wlan0...                [FAILED]

The boot sequence stops and then resumes after exactly 60 seconds!
The KDE Network Device Manager shows it recognizes the Atheros chipset, 
but I can't "Activate" it.
A dmesg dump shows:
          ath5k phy0: Atheros 2425 chip found (MAC: 0xe2, PHY: 0x70
(Incidentally, it works OK in Vista.  Their Device Manager shows the 
chip is an Atheros AR007)

Any advice on how to correct the "invalid argument" and to proceed would 
be greately appreciated.

Bob Kahl