by , 7:30 AM EST, March 2nd, 2007

As if it isn't already enough of a pain to set microwave oven and old VCR clocks, the U.S. government decided we needed a little more to keep us busy, so it changed the Daylight Saving Time dates on us. Even though you are most likely hosed with DST-aware VCRs, your Mac is a different story.

Mac OS X 10.3 and 10.4
If you are using Mac OS X 10.3.9 or 10.4.8, Apple is providing DST updates for the operating system and Java through its Software Update application. You can access Software Update by selecting Apple menu > Software Update.

Mac OS X 10.4.5 also includes updated DST time change information, but the update for Mac OS X 10.4.8 includes more recent time zone information.

Earlier Versions of Mac OS X
Mac OS X 10.2 and earlier versions of Mac OS X 10.3 don't have updates available for the new time change dates. If you are comfortable with rolling up your sleeves and doing a little Unix command line work in Terminal, there are options available for you, too.

New time zone database information is available at the Slackware Web site that you can use to update your Mac's time tables yourself. Instructions are included with the download.

If you aren't all that hip on trying the Slackware package, AFP548 is offering links to alternate patches for Mac OS X 10.2 and 10.3. These downloads include a disk image with the changed files and scripts to build the required source from those changes.

To verify your Mac's DST date change settings are correct type zdump -v /etc/localtime | grep 2007 at the command line in the Terminal application. The command returns the dates your Mac will use when switching DST settings. It should show March 11 and November 4.

Use Terminal to verify your DST date settings.

For those intrepid souls looking for even more knowledge about time zone and DST data, there is a wealth of information at the Sources for Time Zone and Daylight Saving Time Data Web site.

Old School
Not everyone is comfortable with command line action, and yes, there are still Mac users that rely on Mac OS 9.2 or earlier. If you fall into either of those camps, you'll need to start adjusting your Mac's clock manually, just like you do with that trusty old VCR.

In Mac OS X 10.3.8 and earlier do this:

• Launch System Preferences. You can find it by choosing Apple menu > System Preferences.
• Select the Date & Time Preference Pane.
• Uncheck Set date & time automatically.

In Mac OS 9.2, do this:

• Open the Date & Time Control Panel. You can find it by choosing Apple menu > Control Panels > Date & Time.
• Uncheck Set Daylight-Saving Time Automatically.

Disable the automatic Daylight Saving setting in Mac OS 9.

About that old VCR... You're on your own.