本扩展模块作为 PHP 内核的一部分，无需安装即可使用。
Note: Getting the latest timezone database
The latest version of the timezone database can be installed via PECL's » timezonedb. For Windows users, a pre-compiled DLL can be downloaded from the PECL4Win site: » php_timezonedb.dll.
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