src/Pure/drule.ML

--- a/src/Pure/drule.ML	Fri Nov 26 22:04:33 2010 +0100
+++ b/src/Pure/drule.ML	Fri Nov 26 22:29:41 2010 +0100
@@ -891,7 +891,7 @@
         handle TYPE (msg, _, _) => err msg;
 
     fun zip_vars xs ys =
-      zip_options xs ys handle Library.UnequalLengths =>
+      zip_options xs ys handle ListPair.UnequalLengths =>
         err "more instantiations than variables in thm";
 
     (*instantiate types first!*)