Continuing on from his previous post, Davey Shafik has posted a more complete look at his Zend_Service_Server paackage.
Well, after my tease the other day, let me announce the official proposal for Zend_Service_Server: Zend_Service_Server Proposal.
The proposal mentions an "automated SOAP/XML-RPC/REST server that will expose any code using any of the above protocols. Zend_Service_Server will also generate human-readable documentation." It lists out the requirements, dependencies, and the method of operation (including sample cases with code).