Beginning in 2007, Daylight Saving Time (DST) is extended one month and begins for most of the United States at 2 a.m. on the Second Sunday in March to 2 a.m. on the First Sunday of November. The new starts and stop dates were set in the Energy Policy Act of 2005:

• New Start: Second Sunday of March (11 Mar. 2007)

• New End: First Sunday of November (4 Nov. 2007)

These changes affect scheduling and calendaring applications as well as any applications that will perform date calculations over the four weeks that the Energy Policy Act of 2005 adds to DST.

Users can make manual adjustments to their devices and calendars. For example, if you program your VCR to record your favorite show, your machine will be off by an hour unless you manually adjust it.

How Do I Prepare My Personal Computer for the Early Daylight Time Saving?

To update a personal computer, users have to identify which operating system they are running on their computers and get the appropriate patch. Computers using Windows XP SP2 and Apple's OS-X 10.4 operating systems should handle the time change smoothly as long as users have downloaded regular system updates. If you are a computer user who chooses not to take any action, and you live in the U.S. or Canada, your system clock and calendar will no longer automatically adjust for Daylight Saving Time at the proper time each year. This means that you will adjust 3 weeks late in the spring and 1 week early in the fall.

Microsoft Windows Users: Microsoft made patches available so computers can automatically adjust for the earlier change. For instance, users of Windows XP SP2 and 2003 Windows Server may visit http://www.microsoft.com/windows/timezone/DST2007.mspx to get the supporting patch. However, Microsoft has not published any updates for Windows 2000 or NT; it is providing a hotfix - but only to the companies that have an extended support contract. Fortunately, IntelliAdmin has developed patches for Windows 98, ME, NT and 2000. To download the corresponding update, visit http://www.intelliadmin.com and check out their freeware downloads menu.

Apple Users: Currently, Apple has only released updates for Mac OS X 10.4.6 and later versions. The patch can be downloaded by visiting http://docs.info.apple.com/article.html?artnum=303411. But what about Mac OS X 10.3? Apple has not released a patch to update the time information for this version of the Mac OS. The clocks on computers running 10.3 or earlier will not show the correct time for three weeks in March and one week in November unless users do one of the following:

• Change computers' clocks manually to the new "correct" time when Daylight Saving Time takes effect on March 11, 2007, and then again on April 1, 2007 (when those earlier versions of Mac OS X try to change it based on the old rules). Users will similarly have to adjust their computers' clocks on October 28, 2007 and November 4, 2007.
• Download a patch which is not supported by Apple from http://www.afp548.com/. The patch and a series of installation packages for Mac OS X 10.2 or higher were developed by Ian Ward Comfort at Stanford University.

How About Other Consumer Devices?

Many devices are based off of a network, so if the proper adjustments are made to that network, those changes can be deployed to those devices quickly and easily. The digital clocks on cell phones are generally synched with the service provider's network clock. For users of cell phones and smart phones that run on the Windows Mobile operating system, Microsoft advises that individuals consult their service provider. Most cable and satellite television tuners and digital video recorders will receive an update automatically with the current show schedule.

For many users, the DST 2007 change will be a relatively minor nuisance, requiring them to manually adjust the time on their devices. However, the actual economic exposure to back-office systems is largely unknown, and IT professionals will have to exercise due diligence. The most significant business implications might occur in select industries or applications in which time synchronization is critical. An example of this scenario is financial applications that use time-based calculations, such as compound-interest assessments based on hours.

Below are other resources for managing 2007 Daylight Saving Time:

Apple: http://docs.info.apple.com/article.html?artnum=303411

Linux: http://packages.debian.org/unstable/libs/tzdata

Microsoft: http://www.microsoft.com/windows/timezone/DST2007.mspx

Sun: http://www.sun.com/bigadmin/features/techtips/dst_changes.html

IBM: http://www.ibm.com/support/alerts/daylightsavingstimealert.html

Lotus Notes: http://www-1.ibm.com/support/docview.wss?uid=swg21245334

Hewlett-Packard: http://h71000.www7.hp.com/dst.html

BEA Systems: http://support.bea.com//support_news/Patch_for_2007_Daylight_Savings_Time_Changes.jsp

PeopleSoft: http://peoplesoftexperts.blogspot.com/2006/10/impact-of-us-daylight-saving-time.html