centos的升级源一般最高版本是5.2.6, 用以下办法可以升级到5.2.9
64位版本
wget http://download.fedora.redhat.com/pub/epel/5/x86_64/epel-release-5-3.noarch.rpm
rpm -ivh epel-release-5-3.noarch.rpm
wget http://rpms.famillecollet.com/el5.x86_64/remi-release-5-7.el5.remi.noarch.rpm
rpm -ivh remi-release-5-7.el5.remi.noarch.rpm
32位版本
wget http://download.fedora.redhat.com/pub/epel/5/x86/epel-release-5-3.noarch.rpm
rpm -ivh epel-release-5-3.noarch.rpm
wget http://rpms.famillecollet.com/el5.x86/remi-release-5-7.el5.remi.noarch.rpm
rpm -ivh remi-release-5-7.el5.remi.noarch.rpm
更新
yum --enablerepo=remi update php
安装
yum --enablerepo=remi install php