Hydra Web Presentation Server is designed to detect the web browser and serve the page to the standards that browser expects. Hydra uses XML to describe the pages and allows for server side support of XHTML 2.0, XForms and XInclude.
phpBeans provides software and specifications for enabling n-tier development within PHP, such as the phpBeans Object Server, and interoperable with other languages as well. phpBeans can be downloaded from http://www.sitelliteforge.com/