mcrypt is built in for PHP 5.3.x on windows, you don't need to do anything with a dll anymore.
Pré-requis
Ces fonctions utilisent » mcrypt. Pour utiliser cette bibliothèque, téléchargez le fichier libmcrypt-x.x.tar.gz sur » http://mcrypt.sourceforge.net/ et suivez les instructions d'installation fournies.
Depuis PHP 5.0.0, vous avez besoin de la version 2.5.6 ou suivant de la bibliothèque libmcrypt.
Les utilisateurs de Windows trouveront la bibliothèque dans la version Windows de PHP 5.3. La version binaire Windows de PHP 5.3 utilise la version statique de la bibliothèque MCrypt, aucune DLL n'est nécessaire.
Si vous compilez PHP avec la bibliothèque libmcrypt 2.4.x, les algorithmes suivants sont supportés : "CAST", "LOKI97", "RIJNDAEL", "SAFERPLUS", "SERPENT" ainsi que les chiffrements suivants : "ENIGMA" (chiffrement), "PANAMA", "RC4" et "WAKE". Avec libmcrypt 2.4.x un autre mode de chiffrement est disponible : "nOFB".
Both mcrypt and libmcrypt are available through the linked website. You simply have to click the "Browse all files" or similar link once on the "development site" and not just look for the default Sourceforge download button.
If installing libmcrypt from RPM, you need both libmcrypt*.rpm and libmcrypt-devel*.rpm. I found RPMs for both were available for most platforms on this page:
http://rpmforge.net/user/packages/libmcrypt/
Also files.edin.dk does not seem to carry the win32 files anymore.
I found the libmcrypt-2.5.7.tar.gz file here: ftp://mcrypt.hellug.gr/pub/crypto/mcrypt/libmcrypt
The mcrypt link above only has mcrypt-2.x.x.tar.gz files which when compiled said it was missing the libmcrypt file. The libmcrypt-2.5.7.tar.gz worked when compiled and installed on Fedora. I had to use configure options --disable-posix-threads --enable-dynamic-loading for libmcrypt, and -with-mcrypt=usr/local/include configure option for php, which is the folder with mcrypt.h
