The 5.5.4 version of PHP can be downloaded from Softpedia
PHP, an HTML-embedded scripting language with syntax borrowed from C, Java, and Perl, with a couple of unique PHP-specific features thrown in, has been updated to version 5.5.4.PHP 5.x includes a new OOP model based on the Zend Engine 2.0, a new extension for improved MySQL support, built-in native support for SQLite, and much more.
PHP 5.5.4 features a large number of improves and especially fixes. For example, fputcsv() has been improved in order to allow users to specify an escape character, a curl memory leak has been fixed, and an issue with the return types of password API helper functions has been fixed.
You can check out the official changelog in the readme file incorporated in the source package for more details about this release. Download PHP 5.5.4 right now from Softpedia.