Seriously does no one have any ideas? Others with this issue said the only solution was to reinstall OSX!
I'm not alone: http://discussions.apple.com/thread.jspa?threadID=846406
I managed to change the message slightly by removing the Airport network interface option to read: *+...not valid UTF-8, ""+*. But after re-enabling Airport, the original message returned: *+...not valid UTF-8, "�SMB012"+*
Just in case any else has this problem and finds this thread, I've found the fault. With help from an other user, I ran the configd in debug and checked all the bundles. Running the following gave loads of odd messages in System.log:
*sudo /usr/libexec/configd -dv -t /System/Library/SystemConfiguration/PowerManagement.bundle*
Assuming power must be to blame, I removed the battery and the messages stopped!
The battery must be faulty and sending codes to the Mac that it doesn't understand.
I have a similar error coming from powerd and from any program that checks the battery's status (iStat in Dashboard, System Information/Profiler)
3/31/12 1:52:18.076 PM powerd: FIXME: IOUnserialize has detected a string that is not valid UTF-8, "�SMB012".
It seems the battery's serial number is using a non UTF-8 character. This has happened to me with two third-party batteries, but I don't think it's happend with an authentic apple battery. When I take the battery out, the messages stop.
I'm on a 15" 2.2GHz Core 2 Duo MacBook Pro 2007, this has happened with 10.6 through 10.7.3.
I think it might also be causing my mac to crash. Often, it will crash completely (shut off power altogether) immediately after displaying this message.
Also, my mac won't enter safe sleep when the battery reaches a low charge level.
I also had this problem. I was using an Anker battery. I removed it (just a few minutes ago!), am running the laptop of off wall plug power with no battery, and the error messages stopped. I don't know if I'll be able to run the computer without rebooting for days, to verify, but this seems like the fix.
Thanks to the users who tracked this down; it's been an issue for months for me.