Some of the existing E_ERROR conditions have been converted to something that you can catch with a user-defined error handler. If an E_RECOVERABLE_ERROR is not handled, it will behave in the same way as E_ERROR behaves in all versions of PHP. Errors of this type are logged as Catchable fatal error.
This change means that the value of the E_ALL error_reporting constant is now 6143, where the previous value was 2047. Because PHP constants have no meaning outside of PHP, in some cases the integer value is used instead so these will need to be adjusted. So for example if you are setting the error_reporting mode from either the httpd.conf or the .htaccess files, you will need to adjust the value accordingly. The same applies if you use the numeric value rather than the constant in your PHP scripts.
As a side-effect of a change made to prevent duplicate error messages when track_errors is On, it is now necessary to return FALSE from your error handler in order to populate $php_errormsg. This provides you fine-grain control over the levels of messages stored.