ORBIT-USER: Error setting bit-rate?

[Andrea G Forte]

Hi all,

I am using the orbit handler and after I turn on the nodes and try to 
set channel and bit-rate, I get the following:
Error for wireless request "Set Frequency" (8B04) :
    SET failed on device ath0 ; Invalid argument.
Error for wireless request "Set Frequency" (8B04) :
    SET failed on device ath0 ; Invalid argument.
Error for wireless request "Set Bit Rate" (8B20) :
    SET failed on device ath0 ; Invalid argument.
Error for wireless request "Set Bit Rate" (8B20) :
    SET failed on device ath0 ; Invalid argument.

Any idea why this is happening?
Thanks a lot,
-Andrea