new ath and Michael MIC

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

I had a working laptop (wpa_supplicant) + desktop (hostapd) setup, both
with AR5212 based cards. I'm assuming that the only part which changed
recently is the ath driver from binary blob to source. All worked after
upgrading the laptop. Since upgrading the desktop, I get Michael MIC
errors (and that entails the famed TKIP countermeasures). Any idea
what to try?

Cheers,

Patrick