Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
The New Zealand government announced that the DST dates have changed for 2007 as follows.
Start date and time
Last Sunday in September, 2:00 A.M.
First Sunday in October, 2:00 A.M.
End date and time
First Sunday in April, 3:00 A.M.
Third Sunday in March, 3:00 A.M.
For more information about this problem, click the following article number to view the article in the Microsoft Knowledge Base:
937653 You experience one or more issues in Exchange Server 2003 after the daylight saving time period for New Zealand changes in 2007
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.