I've just noticed today, that the apm manager has what appears to be a
bug.

Overnight, my battery ran down to a low state.  Even with the AC adapter
plugged in, the apm keeps shutting down the system with a "battery state
critical" message.  The only way it will run is to remove the battery so
it is running on AC.

There's nothing wrong with the battery or the AC adapter, CE will run
fine and will happily let the battery charge away.  Somehow, netbsd
doesn't seem to know or care that the AC is plugged in.