<?php
ini_set('date.timezone', 'Europe/Lisbon');
ini_set('intl.default_locale', 'en_US');
$cal = IntlCalendar::createInstance();
print_r($cal->getTimeZone());
$cal->setTimeZone('UTC');
print_r($cal->getTimeZone());
$cal = IntlCalendar::fromDateTime('2012-01-01 00:00:00 GMT+03:33');
print_r($cal->getTimeZone());
     
    The above example will output:
IntlTimeZone Object
(
    [valid] => 1
    [id] => Europe/Lisbon
    [rawOffset] => 0
    [currentOffset] => 3600000
)
IntlTimeZone Object
(
    [valid] => 1
    [id] => UTC
    [rawOffset] => 0
    [currentOffset] => 0
)
IntlTimeZone Object
(
    [valid] => 1
    [id] => GMT+03:33
    [rawOffset] => 12780000
    [currentOffset] => 12780000
)