Adapted to changes in setup of cases method.

--- a/src/FOL/FOL.thy	Sat Jan 30 16:59:49 2010 +0100
+++ b/src/FOL/FOL.thy	Sat Jan 30 17:01:01 2010 +0100
@@ -383,6 +383,7 @@
     val atomize = @{thms induct_atomize}
     val rulify = @{thms induct_rulify}
     val rulify_fallback = @{thms induct_rulify_fallback}
+    val equal_def = @{thm induct_equal_def}
     fun dest_def _ = NONE
     fun trivial_tac _ = no_tac
   );