KB article: OWA on Exchange Server 2003 SP2 - daylight savings changes in Western Australia
The time settings in Outlook Web Access on Exchange Server 2003 SP2 may not reflect the change to Western Australia daylight saving time during the transition period
Western Australia is introducing daylight saving time for a three-year trial period. The trial period starts at 2 A.M. on December 3, 2006. In Microsoft Outlook Web Access on Microsoft Exchange Server 2003 Service Pack 2 (SP2), the time settings may not reflect the change to daylight saving time during the transition period. This transition period starts at 2 A.M. on December 3, 2006. This period ends at 2 A.M. on March 25, 2007.
This problem occurs because Outlook Web Access maintains internal tables to track time zone information. The tables are not updated if changes are made to the time zone settings in the operating system.