SOA in Rails

For my master thesis I am researching challenges in using Rails for implementing Service-Oriented Systems. In my case studies I have found that Rails lacks well-integrated functionality for some common tasks. Among these tasks are:

• Accessing a non-Rails REST-full resource
• Accessing an XML-RPC or SOAP service (without ActionWebService)
• Exposing an XML-RPC or SOAP service (without ActionWebService)

I have designed two simple plugins that could provide a framework for integrating most of this functionality. I would like to use this session to briefly present my case studies and the plugins I designed, and then start a discussion. Subject of the discussion will be what problems are encountered when using Rails for implementing Service-Oriented Systems, And what tools are available for dealing with these problems.