Apple Support Document on the iOS 4.1 Daylight Savings Time Alarm Bug

Apple:

To resolve this behavior for existing alarms, set the repeat interval to Never. You will need to reset these alarms for each day you need them.

After November 7th, 2010, you can set your alarms to repeat again.

The bug is apparently fixed in iOS 4.2, but I doubt 4.2 is shipping before November 7 anyway.

★ Wednesday, 3 November 2010