Upgrading CentOS 5 from PHP 5.1 to 5.3

 see what is installed (assuming php-mcrypt & php-mhash are installed

yum list installed | grep php | cut -d' ' -f1
typical result:
php.x86_64
php-cli.x86_64
php-common.x86_64
php-devel.x86_64
php-gd.x86_64
php-imap.x86_64
php-ldap.x86_64
php-mbstring.x86_64
php-mcrypt.x86_64
php-mhash.x86_64
php-mysql.x86_64
php-odbc.x86_64
php-pdo.x86_64
php-pear.noarch
php-xml.x86_64
php-xmlrpc.x86_64

 removes the 16 packages above (make sure there is nothing above you want to keep)

 Check that only the packages above are listed before you press yes

yum remove php php-*

    See what php53 provides:

yum search php53 | cut -d' ' -f1 | grep php

    Notice packages missing: php-mhash php-pear (note mhash is deprecated)

yum install php53 php53-cli php53-common php53-devel php53-gd php53-imap php53-ldap php53-mbstring\
 php53-mysql php53-odbc php53-pdo php53-xml php53-xmlrpc php53-mcrypt

    Can install php-pear back in again—it seems this doesn’t have 5.1 dependencies

yum install php-pear

    Have to put back any changes made in /etc/php.ini, e.g.:
        memory_limit = 128M
        post_max_size = 40M
        upload_max_filesize = 20M
    Find the [Date] section, uncomment the timezone line and add something like:
        date.timezone = 'America/Toronto'

service httpd restart

Install mcrypt from source

yum install php53-devel libmcrypt-devel gcc

    first get php version 5.3.6 (above 5.3.6 fails with PHP_FE_END undeclared in devel library)
    Check latest version here: us2.php.net/releases/#5.3.3

ver=php-5.3.6
cd ~
wget http://www.php.net/get/$ver.tar.gz/from/us3.php.net/mirror
tar xf $ver.tar.gz

    now run one line at a time:

cd ~/$ver/ext/mcrypt/
phpize
aclocal
./configure
make
make test #to help make PHP better
make install
echo "extension=mcrypt.so" > /etc/php.d/mcrypt.ini
service httpd restart
rm -Rf ~/$ver

Update APC

yum install pcre-devel
pecl install -f apc

    add extension=uploadprogress.so to /etc/php.ini

Update phpMyAdmin

    If installed by Rimu script, check here: ls /etc/httpd/conf.d/ to see if yum has renamed conf file
    Upgrade to new version here: drup.org/upgrading-phpmyadmin

Useful Links

    This article was very helpful:
        chrisjean.com/2011/06/24/upgrade-php-5-1-or-5-2-to-5-3-on-centos/
    Other useful links:
        linuxnet.ch/groups/linuxnet/wiki/8457a/