I was having problems with WEP (in 2.6.19, but the relevant code
doesn't seem to have changed), which I eventually tracked down to this:
ieee80211-crypt-wep tries to use "ecb(arc4)", which works fine if ecb,
arc4, and cryptomgr are already loaded, but doesn't cause them to be
loaded if only arc4 is loaded.
I haven't tried with arc4 not loaded, but I did try arc4,cryptomgr and
arc4,ecb; neither of these caused the third one to be loaded.
(I also had crypto_algapi, michael_mic, and aes loaded, if that matters)
I can test stuff without too much trouble, but I'm out of ideas for things
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