Keeping OS X and XP on the same timezone
I’ve been using Mac OS X and WinXP Pro on my Macbook Pro for a while. One thing I noticed is that the system’s clock shifts a few hours back and forth across OS reboots, a problem for which I had no explanation until now.
[...] Windows XP reads and writes the hardware clock in terms of the local time zone. If UTC is 12:00 and I’m in GMT+2 Windows will write the time to the hardware clock as 14:00. Mac OS X on the other hand assumes that the hardware clock is set to UTC, and therefore displays the time as 16:00 after I reboot from Windows into OS X.
While I wait for a fix from Apple – I doubt Microsoft cares about this – in a future Boot Camp update, at least I know the cause.
Thanks to Niels Mäkel at Makel.org for the information.