Suhosin looked dead last time I looked and people sticking to 5.3 is discussed here a year ago and PHP's lack of a function whitelist amongst other things worries me enough to consider abandoning it without it.
http://openbsd.7691.n7.nabble.com/PHP-5-4-5-and-Suhosin-td236684.html The extension appears to be alive and kicking though with two releases since the below. https://github.com/stefanesser/suhosin/blob/master/Changelog 2014-02-24 - 0.9.35 - From now only PHP >= 5.4 is officially supported - Fix problems with the hard memory_limit on 64 bit systems - Fix problems with user space session handler due to change in PHP 5.4.0 - Add changes in PHP 5.5 session handlers structures for PHP 5.5 compability - Fix std post handler for PHP >= 5.3.11 - Fix suhosin logo in phpinfo() for PHP 5.5 - Change fileupload handling for PHP >= 5.4.0 to use an up to date RFC1867 replacement code - Adapted suhosin to PHP 5.5 executor - Added some test cases for various things - Added suhosin.log.stdout to log to stdout (for debugging purposes only) - Add ini_set() fail mode to suhosin.disable.display_errors - Fix suhosin.get/post/cookie.max_totalname_length filter - Refactor array index handling in filter to make it work always - Added support for PHP 5.6.0alpha2 - WARNING: FUNCTION WHITELISTS/BLACKLISTS NEVER WORKED CORRECTLY WITH PHP < 5.5
