2009 Aluminum Keyboard Firmware Update 1.0
... This firmware update improves battery performance of the 2009 Aluminum Apple Wireless Keyboard when used in combination with other Bluetooth devices (example. Magic Mouse, Bluetooth headsets).
Your 2009 Aluminum Apple Wireless Keyboard must be connected or paired to perform this update.
2009 Apple Aluminum Keyboard, Mac OS X 10.5.8 or 10.6.2 or later