It took me a couple of hours today :-(...
Removing the SeamMTMatcher bean from seam-deployers-jboss-beans.xml works for me (I can finally hot-deploy facelets templates again).
Don't know yet if there are any side effects.
Kenneth, did you find a solution to this problem? I went thru the JIRA case and all referenced forums, but I didn't see a definitive answer as to how to restore this functionality.
Removing SeamMTMatcher didn't solve the problem.
This did not solve the issue for me either.