ICal
The release of Snow Leopard introduced several bugs into Snow Leopard, with regard to iCal alarms. These problems include alarms not firing; all alarms being set to one fixed date and time in the past, preventing them from firing; alarms from repeat events being fired for all historic occurrences of that repeated event, resulting in dozens of alarms for one event. Updates to Snow Leopard 10.6.1 and 10.6.2 have not addressed these problems.