/etc/sysconfig/network/scripts/ifup-wireless generates invalid iwconfig lines,
at least for atheros cards:

spellbook:/etc/sysconfig/network/scripts # ifup ath0
    ath0      device: Atheros Communications, Inc. AR5212 802.11abg NIC (rev 01))
    ath0      configuration: wlan-id-00:05:4e:4b:ed:df
command 'iwconfig ath0 key open a59blahblahblahblahblah [1] key 128 [2] key 128
[3] key 128 [4]' returned
 Error for wireless request "Set Encode" (8B2A) :
    SET failed on device ath0 ; Invalid argument.
setting encryption key FAILED, aborting interface setup


The problem is the call to print_key at (or around) line 239:

   eval WIRELESS_KEY_$i="$(print_key $K $WIRELESS_KEY_LENGTH)"

if $K is empty/unset, then this is equivalent to

   eval WIRELESS_KEY_$i="$(print_key  $WIRELESS_KEY_LENGTH)"

meaning the $WIRELESS_KEY_LENGTH (128) is incorrectly interpreted as a
key (and the key length is defaulted by print_key), resulting in spurious
invalid keys in the iwconfig command.

Changing the line to

   eval WIRELESS_KEY_$i=$(print_key "$K" $WIRELESS_KEY_LENGTH)

fixes it, and I think should not cause any other problems, but I didn't
look carefully, so that might not be quite right.