PHP 5.3.0 introduces two new error levels: E_DEPRECATED and E_USER_DEPRECATED. The E_DEPRECATED error level is used to indicate that a function or feature has been deprecated. The E_USER_DEPRECATED level is intended for indicating deprecated features in user code, similarly to the E_USER_ERROR and E_USER_WARNING levels.
The following is a list of deprecated INI directives. Use of any of these INI directives will cause an E_DEPRECATED error to be thrown at startup.