We found that some "1 day" events now span 2 days. Some are single instance and some are recurring. How can we fix this?

Q: We performed the rebasing on our Exchange 2003 server. We found that some "1 day" events now span 2 days. Some are single instance and some are recurring. How can we fix this?
A: This is what happens when an event that is marked as an ‘all day’ event stretches across two days. This can be a result of one of the following scenarios: 1) You have updated the OS to reflect the DST2007 rules and have not yet run the Outlook Time Zone Data Update Tool or 2) You have not updated the OS but the appointments have been rebased to reflect the DST2007 rules (perhaps by an administrator running the server-side tool or by the user running the Outlook Time Zone Data Update tool from another machine) and the only problem is that the machine in which they’re viewing their Calendar is viewing them under DST2006 rules. Getting into a state in which the appointments are encoded in DST2007 rules (support.microsoft.com/kb/931667/ and www.microsoft.com/downloads/details.aspx?familyid=e343a233-b9c8-4652-9dd8-ae0f1af62568&displaylang=en) and the machine being used to view them has the DST2007 patch (support.microsoft.com/kb/931836) applied should get you back into the expected state.