安装步骤：
1，#wget http://museum.php.net/php5/php-5.3.3.tar.gz
2，解压：#tar -zxvf php-5.3.3.tar.gz
3，#cd php-5.3.3/ext/mcrypt
4，#phpize
5，#./configure --with-php-config=/usr/sbin/php/bin/php-config
6，#make && make install
7，修改php.ini增加extension=mcrypt.so
8，重启httpd:#service httpd restart
注意，如果提示需要安装libmcrypt,则需要先安装libmcyrpt:
1,#wget http://sourceforge.net/projects/mcrypt/files/Libmcrypt/2.5.8/libmcrypt-2.5.8.tar.gz/download
2,#解压，进入目录 #cd libmcypt-2.5.8
3,#./configure
4,# make && make install
6,再编译一遍mcrypt，即可成功