--- a/Nominal/Nominal2_FSet.thy	Sat Mar 27 13:50:59 2010 +0100
+++ b/Nominal/Nominal2_FSet.thy	Sat Mar 27 14:38:22 2010 +0100
@@ -3,7 +3,7 @@
 begin
 
 lemma permute_rsp_fset[quot_respect]:
-  "(op = ===> op \<approx> ===> op \<approx>) permute permute"
+  "(op = ===> list_eq ===> list_eq) permute permute"
   apply (simp add: eqvts[symmetric])
   apply clarify
   apply (subst permute_minus_cancel(1)[symmetric, of "xb"])