Seeing Jon's post, I think I need to clarify something. I'm a fan of automatic roadmap dispensers. And as long as toolkits understand that the end result is a description of a message that you would accept, and not saying anything about what other messages you might also accept, then you can make use of namespaces and named parameter associations to cope with change.
So when I saw David Bau's paper this morning, I made a note of it here and then fired off a message to soapbuilders to put it on the agenda for next month's meeting.