Posted by 因为要用到Zend Optimizer，但Zend Optimizer v3.3.9并不支持php5.3，特别是在国内一些程序开发商，一直使用旧的平台，新的zend guard与Zend Optimizer并不兼容，所以近切的需要将php5.3降级为5.2
因为这个问题，我折腾了整整一天，按照网上的教程，使用karmic源（UBUNTU 9.10),一直没有成功。一直安装的都是PHP5.3.3
后终于找到原因：ubuntu 9.10的支持日期已经过了，网络上面的karmic源全是错误的，正常的源karmic.list应该是：
# deb cdrom:[Ubuntu 10.04 LTS _Lucid Lynx_ - Release amd64 (20100429)]/ karmic main restricted # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://old-releases.ubuntu.com/ubuntu/ karmic main restricted deb-src http://old-releases.ubuntu.com/ubuntu/ karmic main restricted ## Major bug fix updates produced after the final release of the ## distribution. deb http://old-releases.ubuntu.com/ubuntu/ karmic-updates main restricted deb-src http://old-releases.ubuntu.com/ubuntu/ karmic-updates main restricted ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http://old-releases.ubuntu.com/ubuntu/ karmic universe deb-src http://old-releases.ubuntu.com/ubuntu/ karmic universe deb http://old-releases.ubuntu.com/ubuntu/ karmic-updates universe deb-src http://old-releases.ubuntu.com/ubuntu/ karmic-updates universe ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team, and may not be under a free licence. Please satisfy yourself as to ## your rights to use the software. Also, please note that software in ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team. deb http://old-releases.ubuntu.com/ubuntu/ karmic multiverse deb-src http://old-releases.ubuntu.com/ubuntu/ karmic multiverse deb http://old-releases.ubuntu.com/ubuntu/ karmic-updates multiverse deb-src http://old-releases.ubuntu.com/ubuntu/ karmic-updates multiverse ## Uncomment the following two lines to add software from the 'backports' ## repository. ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. # deb http://old-releases.ubuntu.com/ubuntu/ karmic-backports main restricted universe multiverse # deb-src http://old-releases.ubuntu.com/ubuntu/ karmic-backports main restricted universe multiverse ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. # deb http://archive.canonical.com/ubuntu karmic partner # deb-src http://archive.canonical.com/ubuntu karmic partner deb http://old-releases.ubuntu.com/ubuntu karmic-security main restricted deb-src http://old-releases.ubuntu.com/ubuntu karmic-security main restricted deb http://old-releases.ubuntu.com/ubuntu karmic-security universe deb-src http://old-releases.ubuntu.com/ubuntu karmic-security universe deb http://old-releases.ubuntu.com/ubuntu karmic-security multiverse deb-src http://old-releases.ubuntu.com/ubuntu karmic-security multiverse
操作过程如下：
1、下载附件
ubuntu安装php5.2所需文件 (下载675 )
karmic.list 放在/etc/apt/sources.list.d目录中
php 放在/etc/apt/preferences.d目录中
2、运行命令
sudo apt-get update sudo apt-get remove php5 libapache2-mod-php5 php5-xsl php5-gd php-pear php5-mysql php5-curl php5-memcache sudo apt-get install php5 libapache2-mod-php5 php5-xsl php5-gd php-pear php5-mysql php5-curl php5-memcache
我在php文件中还加入了 libapache2-mod-php5，php5-mcrypt，php5-dev，php5-xcache
例如需要安装xcache,直接运行：
sudo apt-get install php5-xcache
如果需要能过APT-GET安装其它的组件，需要更改上面的php文件，在最后面加入组件的名字即可，非常方便