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Daylight Savings Time Changes 

In 2005, the government passed the Energy Policy Act, to extend daylight savings time by four weeks, which means that daylight savings time will start three weeks earlier (second Sunday in March) and will end one week later (first Sunday in November).

General Recommendations

There are steps every organization should take to prepare their systems for daylight savings time:

  1. Identify what platforms you are using in-house
  2. Look at the operating systems you have
  3. Check with each of your vendors to find out what changes you will need to make to be in compliance
  4. Depending on your vendor and OS, upgrade to a new level
  5. Depending on your vendor and OS, apply suggested patches
  6. Apply upgrades or patches as needed
  7. Look at your individual applications including those that reside on mobile devices
  8. Consult with each application vendor to receive upgrades or patches
  9. Look at your storage environment including storage controllers and SAN boxes

ASNA Products

All ASNA products rely upon the machine operating system to provide the correct time and time durations.


The iSeries or System i began to automatically update its system time for daylight savings with V5R3. For those installations that employ automatic time adjustment, IBM is updating i5/OS with a PTF that will automate the changes needed to support the new DST information. The updates for DST for i5/OS are available as:

  • V5R4M0 SI26040 and SI25990
  • V5R3M0 SI26039 and SI25991

For more information:


Updated time zone definitions ship with Windows Vista. Microsoft provides updates for Windows XP Service Pack 2 (SP2), Windows Server 2003, and Windows Server 2003 Service Pack 1 (SP1). Download links for this update are available from Microsoft Knowledge Base article 928388.

DST, Daylight Savings Time