When I unplug the power cord from my MacBook (unibody - late 2008), the battery icon in Mac OS X stops updating it's level and the icon does not change. The menu says that it is running on power adapter even when it is unplugged and that the computer is not charging. The hardware battery indicator continues to show the correct battery level. Normally I should get a warning when the battery is about to die (running on emergency power) but I don't, instead it just runs out of battery and shuts down. Has anyone else seen this?