Zend Server Cluster Manager extends Zend Server to provide high availability and scalability.

The new product includes:

A fault-tolerant, fast session storage mechanism for Zend Server clusters
Centralized management and monitoring of multiple Zend Server instances
Configuration management to ensure consistency across clustered server
Graceful shutdown and other capabilities for dynamic server environments, such as the Cloud

Zend Server 5.0.2 includes:

Support for the new Zend Server Cluster Manager 5.0
Several PHP 5.2.13 and 5.3.2 patches
Zend Framework 1.10.5
New versions of various 3rd party modules, including MySQL, Oracle OCI8 extension, IBM DB2 extension and others

Happy PHP'ing,
Zend - The PHP Company