<?php

ini_set("intl.error_level", E_WARNING);
$lsb = IntlTimeZone::createTimeZone('Europe/Lisbon');
$gmt = IntlTimeZone::getGMT();
var_dump($lsb->useDaylightTime());
var_dump($gmt->useDaylightTime());
var_dump(intltz_use_daylight_time($lsb));
var_dump(intltz_use_daylight_time($gmt));
?>
==DONE==
<?php

ini_set("intl.error_level", E_WARNING);
$tz = IntlTimeZone::createTimeZone('Europe/Lisbon');
var_dump($tz->useDaylightTime('foo'));
intltz_use_daylight_time(null);