The gnupg extension requires PHP 4.3. To use this extension in an OO style, PHP 5 is required.
This extension requires the » gpgme library
jimjag at gmail dot com (2013-06-28 21:13:30)
gnupg-1.3.2 (the latest) does not build under PHP 5.4.x or PHP 5.5.x... there are numerous suggested patches but nothing official.