이 함수들은 설치하지 않아도 사용할 수 있습니다; PHP 코어의 일부입니다.
Note: Getting the latest timezone database
The latest version of the timezone database can be installed via PECL's » timezonedb.
Note: Experimental DateTime support in PHP 5.1.x
Although the DateTime class (and related functions) are enabled by default since PHP 5.2.0, it is possible to add experimental support into PHP 5.1.x by using the following flag before configure/compile: CFLAGS=-DEXPERIMENTAL_DATE_SUPPORT=1