Apple posts MacBook SMC Firmware Update 1.1 to address issues with unexpected shutdowns.
http://www.apple.com/support/downloads/macbooksmcfirmwareupdate11.html
Download MacBook SMC Firmware Update 1.1 (<1MB)
From Apple:
MacBook SMC Firmware Update 1.1
About this update
The SMC Update improves the MacBook’s internal monitoring system and addresses issues with unexpected shutdowns. This update is recommended for all MacBook systems, including those that received warranty repair.
Note:
If your MacBook is running Mac OS X 10.4.6, you won’t be able to install the SMC Update until you update to Mac OS X 10.4.8.
MacBooks running Mac OS X 10.4.7 will be able to download and install the SMC Update, so it is not essential that you update your system software, although Apple always recommends updating to the latest version of the system software.
After this update has completed successfully, your SMC Version will be: 1.4f12.
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