Henri has put together a quick-and-dirty validator for HTML5+RDFa (without CURIE support) here:
http://validator.nu/ Select "HTML5+ARIA plus RDFa minus CURIE (totally experimental)" in order to use it. I believe he said that it doesn't have URLs in @rel/@rev support yet, either. You can test it out on the following example that Dan Brickley put together (and I modified, slightly): http://rdfa.digitalbazaar.com/demos/html5/nocuries.html -- manu -- Manu Sporny President/CEO - Digital Bazaar, Inc. blog: Bitmunk 3.1 Website Launch http://blog.digitalbazaar.com/2009/01/16/bitmunk-3-1-website-launch