Updating all the timezone stuff one needs on a LAMP environment: (necessary in Australia because they changed the daylight savings start date once again). I haven't yet been able to convince my hosting provider to go through all this hassle; and the tables are outdated - so Aussie visitors may see an incorrect time on some of my websites for the next week. 

Test:

# zdump -c 2009 -v Australia/Sydney | grep 2008
Australia/Sydney  Sat Apr  5 15:59:59 2008 UTC = Sun Apr  6 02:59:59 2008 EST isdst=1 gmtoff=39600
Australia/Sydney  Sat Apr  5 16:00:00 2008 UTC = Sun Apr  6 02:00:00 2008 EST isdst=0 gmtoff=36000
Australia/Sydney  Sat Oct  4 15:59:59 2008 UTC = Sun Oct  5 01:59:59 2008 EST isdst=0 gmtoff=36000
Australia/Sydney  Sat Oct  4 16:00:00 2008 UTC = Sun Oct  5 03:00:00 2008 EST isdst=1 gmtoff=39600

(If the first two lines contain 'Mar' instead of 'Apr' you've got old tables). e.g. this is what an unpatched system would report:

# zdump -c 2009 -v Australia/Sydney | grep 2008
Australia/Sydney  Sat Mar 29 15:59:59 2008 UTC = Sun Mar 30 02:59:59 2008 EST isdst=1 gmtoff=39600
Australia/Sydney  Sat Mar 29 16:00:00 2008 UTC = Sun Mar 30 02:00:00 2008 EST isdst=0 gmtoff=36000
Australia/Sydney  Sat Oct 25 15:59:59 2008 UTC = Sun Oct 26 01:59:59 2008 EST isdst=0 gmtoff=36000
Australia/Sydney  Sat Oct 25 16:00:00 2008 UTC = Sun Oct 26 03:00:00 2008 EST isdst=1 gmtoff=39600

Debian:

# apt-get update 

# apt-get install tzdata

PHP5.x

# apt-get install php5-dev 

[fetch and save] http://pecl.php.net/get/timezonedb

# tar zxvf timezonedb-xxxxxxx.tgz

# cd timezonedb-xxxxxxx

# phpize

# ./configure

# make

# make install

# echo "extension=timezonedb.so"  > /etc/php5/conf.d/timezonedb.ini

# /etc/init.d/apache2 restart

MySQL:

# mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql -u root mysql -p

(ignore all the errors from Riyadh{NN}, iso3166.tab, and zone.tab)