I'm still seeing the problem, but not nearly as often. I have changed nothing with my Cisco Aironet 1231 AP, except what's been noted in this thread. It would seem that the occurances have been less frequent with the last round of updates to the Airport. I used to see the problem 5-6 times a day. Now I'm down to once every couple of weeks.

What's puzzling is that there is an error that pops in MacOS, that no one seems to know anything about. Even those at the apple forums.