Forum OpenACS Q&A: Re: OpenACS and Web Services
it is me who modified bookshelf to use Amazon's XML RPC based web service. You can see it in action on http://www.thecodemill.biz.
I haven't contributed the modification back into the toolkit as I would prefer a more general solution instead of this one off hack. Also the current bookshelf package doesn't scale very well when integrated with Amazon's web service. The index page of bookshelf shows all books on the shelf and requests additional information from amazon for each book. With more than a handfull of books (and depending on the Internet connection with Amazon) this results in a server time out the first time you request the page. Because results are cached subsequent requests for the index page typically do work. The point is that bookshelf requires some reworking to avoid this problem.
I've also looked investigated adding tDOM support in TclSoap. It is certainly feasable but the maintainer of TclSoap never responded to my offer to help.
Currently I'm not actively developing web services although the need for SOAP and XML RPC capabilities is likely to occur at my work in the forseable future. At which point I'll revisit these topics.