Thanks as well to Bladdernose!
I was having a problem with my iMac not Sleeping, and I suspected it had something to do with a Console message that I was literally getting thousands of per day:
It read "awacsd: Connection failed. Retrying in 10 seconds."
I searched these forums for information on the awacsd process and came up with very little, other than that it had something to do with Back to My Mac. I didn't see how that could be the problem, since I have never used or activated Back to My Mac.
But I read your post here and figured what the heck- I'll try it. So I turned on BTMM in the iCloud Preferences pane, and sure enough got the "Server not responding" message. Soooo, I went ahead and accomplished your Keychain cleaning as described above. And that did it! BTMM activated. I then looked at my Console and the awacsd errors stopped for the first time in a week! And best yet, my Mac now sleeps!
I've now turned off BTMM since I don't use it, but the point is this solved the Awacsd errors and that's great! FWIW, I too suspect that the error was caused by some Mobile Me server (now shut down) that my Mac and the Awacsd process were trying to connect to. Clearing out that Keychain item fixed it! So thanks again!
Dave