Hi, I've seen two or three of those messages in the last year, and I noticed a \n was missing:
--- sys/net80211/ieee80211_crypto_tkip.c Tue Apr 21 02:01:35 2009 +++ sys/net80211/ieee80211_crypto_tkip.c.new Fri Oct 30 20:08:26 2009 @@ -508,7 +508,7 @@ if (ic->ic_flags & IEEE80211_F_COUNTERM) return; /* countermeasures already active */ - log(LOG_WARNING, "%s: Michael MIC failure", ic->ic_if.if_xname); + log(LOG_WARNING, "%s: Michael MIC failure\n", ic->ic_if.if_xname); /* * NB. do not send Michael MIC Failure reports as recommended since -- Jurjen Oskam Savage's Law of Expediency: You want it bad, you'll get it bad.