Most states in the US and all provinces in Canada are about to change the time that Daylight Savings comes into effect.
http://www.microsoft.com/windows/timezone/dst2007.mspx
How can I check that the Zimbra timezone rules are correct for this, or how can I self modify without upgrading to 4.0?
After a little more investigation, I think what will happen is this.
The timezone calculation is done on the Web Client and therefore it is the responsibility of the client platform to set the rules. Therefore the above url from MS has the answers for Windows platforms.
If there is anything happening on the server then as long as we are running Java 1.5-06 (which is what ships with Zim 3.1.4) then the rules here are also correct.
http://java.sun.com/developer/techni...es/Intl/USDST/
I'll have a prowl through the LDAP entries to verify that there is not anything else that may trip things up.
OK I may well be incorrect - there are timezone rules being stored in the Zimbra LDAP config
This is what is loaded for Zimbra 3.1.4:
# (GMT-08.00) Pacific Time (US & Canada) / Tijuana
# (supports Daylight Savings Time)
dn: cn=(GMT-08.00) Pacific Time (US & Canada) / Tijuana,cn=timezones,cn=config,cn=zimbra
objectclass: zimbraTimeZone
cn: (GMT-08.00) Pacific Time (US & Canada) / Tijuana
zimbraTimeZoneStandardDtStart: 16010101T020000
zimbraTimeZoneStandardOffset: -0800
zimbraTimeZoneStandardRRule: FREQ=YEARLY;WKST=MO;INTERVAL=1;BYMONTH=10;BYDAY=-1SU
zimbraTimeZoneDaylightDtStart: 16010101T020000
zimbraTimeZoneDaylightOffset: -0700
zimbraTimeZoneDaylightRRule: FREQ=YEARLY;WKST=MO;INTERVAL=1;BYMONTH=4;BYDAY=1SU
So this says that Daylight Savings starts on the 1st Sunday in April. Whereas it should now say Daylight Savings starts on the second Sunday in March. And ends the last Sunday in October, whereas it should now be the 1st Sunday in November.
On a Zimbra 4.0.5 release the equivalent loaded timezone is (from /opt/zimbra/conf/zimbra.ldif):
# (GMT-08.00) Pacific Time (US & Canada) / Tijuana
# (supports Daylight Savings Time)
dn: cn=(GMT-08.00) Pacific Time (US & Canada) / Tijuana,cn=timezones,cn=config,cn=zimbra
objectclass: zimbraTimeZone
cn: (GMT-08.00) Pacific Time (US & Canada) / Tijuana
zimbraTimeZoneStandardDtStart: 16010101T020000
zimbraTimeZoneStandardOffset: -0800
zimbraTimeZoneStandardRRule: FREQ=YEARLY;WKST=MO;INTERVAL=1;BYMONTH=10;BYDAY=-1SU
zimbraTimeZoneDaylightDtStart: 16010101T020000
zimbraTimeZoneDaylightOffset: -0700
zimbraTimeZoneDaylightRRule: FREQ=YEARLY;WKST=MO;INTERVAL=1;BYMONTH=4;BYDAY=1SU
OK, so this seems like a pretty serious problem, I'll work out a LDAP update script and post. If someone from Zimbra could confirm these findings I'd appreciate it.
Regards,
Chris