I wish I had thought of the simple idea of including a version number. <g> That may be the best solution.good suggestion. you could even dynamically keep the schema up to date and publish it for your clients at a well known URL. Or include a dynamic URL reference to it in the SOAP message.
-- "We do not lose our identity in our relations with others; in part, at least, we achieve our identity by those relations." Tony Blair, 1993