According to numerous Twitter reports, which were then picked up by blogs including and , there’s a problem with non-recurring alarms set from within the Clock application.

I was able to confirm this after a couple of false starts. For the bug to show itself, your iOS device must actually tick over from 11:59 p.m. on December 31, 2010 to 12:00 a.m. on January 1, 2011. (Good news for time travelers!)

Once you’ve passed that special minute and your iPhone has shot off its virtual confetti cannon, the bug occurs: one-time alarms set for 12:01 a.m., for example, won’t go off. (I was able to set a recurring event for every Saturday at 12:03 a.m., and that one went off.)

The workaround for this is easy: set your alarm for New Year’s Day to be an “every Saturday” alarm.

According to a , this bug lasts through January 3, then fixes itself. I haven’t had a chance to test that claim.