diff -r 1b091b3a0d1e -r 0a18f25c16a7 server/hook.py
--- a/server/hook.py	Tue Jan 04 15:31:07 2011 +0100
+++ b/server/hook.py	Tue Jan 04 16:12:48 2011 +0100
@@ -355,6 +355,7 @@
         self.expected = expected
         self.frometypes = more.pop('frometypes', None)
         self.toetypes = more.pop('toetypes', None)
+        assert not more, "unexpected kwargs in match_rtype: %s" % more
 
     @lltrace
     def __call__(self, cls, req, *args, **kwargs):