Description
bool
date_default_timezone_set ( string timezone_identifier )
date_default_timezone_set() sets the default timezone
used by all date/time functions.
Note:
Since PHP 5.1.0 (when the date/time functions were rewritten), every call
to a date/time function will generate a E_NOTICE if
the timezone isn't valid, and/or a E_STRICT message
if using the system settings or the TZ environment
variable.