I've been reading a lot of questions about the MSExTMZCFG Tool in the forums of exchange community. Then, the MsExchangeteam.com guys have published an article about it.
We have put together a step-by-step walkthrough on how to run the Exchange Calendar Update Configuration Tool (MSExTMZCFG.EXE). This is a server-side tool that can be used as part of the 2007 DST process for Exchange. We have also included some information about solutions for commonly seen errors when running the tool.
Please note that the KB article that talks about this package (KB 930879) has additional information about the tool as well as prerequisites and possible complications.
There are 2 files that are downloaded in the above package:
MSEXTMZ.exe - This file extracts time zone information from mailboxes on a server that is running Exchange Server. This file also updates mailbox calendars for a specified list of users by invoking the Outlook tool against each specified user.
MSEXTMZCFG.exe - This file is a configuration tool that describes most of the steps when you update an Exchange Server server.
Read more at source: http://msexchangeteam.com/archive/2007/02/14/435267.aspx