One of the shortcomings of the built-in SOAP library in PHP5+ is the lack of support for auto-generation of WSDL files for web services. PHP2WSDL is an attempt to solve this technical problem, worth checking out:
I have been writing about web technology and software development since 2001. I am the developer of the Alpha Framework for PHP, and the Five.Today personal productivity app. I love open source, technology, and economics.