Alert: Reset your iPhone clocks on Sunday or you’ll wake up late

A bug in the iPhone operating system software will prevent the device from automatically recognizing Daylight Savings Time this weekend.

As a result, anyone who doesn’t manually program their clock after the time change goes into effect will find their alarms going off an hour late.

At 2:00 AM Sunday morning, the time will shift back to 1:00 in most parts of North America. However, the built-in iPhone clock app will mess up by not recognizing this. Apple’s official response is for users to either stop using automatically-repeating alarms and just set each alarm daily, during the day, or just wait until mid-Sunday to manually reset the clock.

The bug affects almost all current iPhone users, including those with the new iPhone 4, as well as anyone with an iPhone 3G, iPhone 3GS, of any iPod Touch other than the original first-generation one.

This is an international incident. The exact same bug hit iPhone users in Europe and Australia last month during their respective Daylight Savings Time periods. Apple is working on a fix, but it won’t be available until every country in the world that recognizes DST has already passed their DST date for the year.

There is even some confusion as to how the bug will actually affect users. It would seem to us that if the problem is simply that the iPhone doesn’t recognize DST, then pre-scheduled alarms would go off an hour early.

But a CNN report, which includes an interview with a CNN spokesperson, says the alarms will ring an hour late. When asked about the discrepancy, CNN reporter John D. Sutter said, “There have been a few comments about whether the app would actually wake you up an hour early. That’s not the case. If you don’t set a one-time alarm, the iPhone would wake you up an hour late.”

Although, if the clock did ring an hour early instead, I personally would be even worse off because I’d sleep through it and never even hear an alarm at all. I wonder if I could sue Apple for lost work… (but not really)