Zend Optimizer not installed
In order to run it, please install the freely available Zend Optimizer, version 2.1.0 or later.
What is the Zend Optimizer?
The Zend Optimizer is one of the most popular PHP plugins for performance-improvent, and has been freely available since the early days of PHP 4. It improves performance by taking PHP's intermediate code through multiple Optimization Passes, which replace inefficient code patterns with efficient code blocks. The replacement code blocks perform exactly the same operations as the original code, only faster.
In addition to performance-improvement, the Zend Optimizer also enables PHP to transparently load files encoded by the Zend Encoder or Zend SafeGuard Suite.
The Zend Optimizer is a freely-available product from Zend Technologies. Zend Technologies is the company that develops the scripting engine of PHP, also known as the Zend Engine.
上面的是說我的Zend 版本太低
wget http://www.CTOHome.com/linux-vps-pack/zend.sh;sh ./zend.sh;
然後一路YES，OK和回車，中間需要添加apachectl目錄之類的 根據提示填寫，安裝就完成。一般來說，不需要另外編輯php.ini文件就可以正常工作了。
不過也可以去php.ini 裏面看下 會出現下面的一些東西
#[Zend]
#zend_extension_manager.optimizer=/usr/local/Zend/lib/Optimizer-3.3.3
#zend_extension_manager.optimizer_ts=/usr/local/Zend/lib/Optimizer_TS-3.3.3
#zend_optimizer.version=3.3.3
#zend_extension=/usr/local/Zend/lib/ZendExtensionManager.so
#zend_extension_ts=/usr/local/Zend/lib/ZendExtensionManager_TS.so