Western Australia Daylight Saving Time: Impact on WebSphere Application Server as of 3 December 2006
 Flash (Alert)
 
Abstract
Information about the impact of time zone changes in Western Australia starting on 3 December 2006. Without the required update to the Java time zone tables, times will be incorrect by one hour.
 
Content
The following link provides more information regarding the change in Daylight Saving Time for Western Australia:
The dates affected are as follows:

03 December 2006 - 25 March 2007
28 October 2007 - 30 March 2008
26 October 2008 - 29 March 2009

After this trial period ends, the Western Australia Parliament will consider extending the period further or making it permanent.

Failure to accommodate the date change may lead to inaccurate data being recorded or displayed. For more information about potential impact, please refer to Possible implications if one does not apply the Daylight Saving Time fixes.

Users of Microsoft® Windows® operating environments should refer to the site Western Australian Daylight Savings Changes for Microsoft Windows for the Year 2006/2007, from the Microsoft support site.

How do I know if my systems could be affected?
All IBM® WebSphere® Application Server releases, including servers, application clients, and plug-ins will be affected by this DST change. In addition, your Operating Systems may also be affected.


Use the IBM Time Zone Update Utility to update Java
The majority of WebSphere Application Server versions can be fixed using the JTZU tool to update Java JREs/SDKs.

Users of WebSphere Application Server may need to use the IBM Time Zone Update Utility (JTZU) to apply updated time zone information to their Java JREs/SDKs to prevent any runtime problems. For more information about the JTZU tool:

  1. Review the following information:
    IBM Time Zone Update Utility for Java
    FAQ: IBM Time Zone Update Utility for Java
  2. Download the utility from IBM developerWorks: IBM Time Zone Update Utility for Java
  3. Run the utility.

The JTZU has been updated to resolve the DST change for Western Australia going into effect on 3 December 2006.

What versions of WebSphere Application Server do not yet have a fix for Western Australia DST?
WebSphere Application Server versions 4.0 and 5.0 installations on HP-UX, and version 4.0 on Solaris do not yet have a fix. The JTZU tool will not be able to address this issue.

To download the WebSphere Application Server V5.0 fix for Solaris, please refer to: Solaris Java 2 SDK 1.3.1 SDK ifix for Western Australia Daylight Saving Time.

Additional information is forthcoming and will be posted here, as it becomes available.



What could happen if I do not update my systems?
Any Western Australia time zone-based application that uses time will be affected.

The following typical scenarios and operations will produce incorrect results as a consequence of using the time offset by one hour.
  • Time format and display
  • Time zone name display
  • Operations that check whether a particular date is in daylight saving time
  • Computations and/or business logic based on daylight saving time
  • Any of the above that run on a system on which time is set to a time zone other than a Western Australia time zone, but does computations based on a Western Australia time zone

Please refer to Possible implications if one does not apply the Daylight Saving Time fixes for information about the consequences of failing to update your systems with the new Western Australia time zone data.

Other useful information about Java and DST:


Change History
8 Dec 2006 Fixed typo in March 2008 date
29 Nov 2006 Initial publication
 
Related information
Java Technology on IBM developerWorks
Olson Time Zone database
FAQ: IBM Time Zone Update Utility for Java
IBM-wide product alerts
 
 
Cross Reference information
Segment Product Component Platform Version Edition
Application Servers Runtimes for Java Technology Java SDK
 
 


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server > Java SDK
Operating system(s): z/OS
Software version: 6.0
Software edition:
Reference #: 1250674
IBM Group: Software Group
Modified date: Dec 19, 2006