diff --git a/ChangeLog b/ChangeLog
index 9b4d5a29ae..9730603f84 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Oct 28 04:38:06 2012  Koichi Sasada  <ko1@atdot.net>
+
+	* vm.c (vm_define_method): remove type and frozen checking.
+	  Checking is done in `rb_singleton_class()'.
+
 Sun Oct 28 00:49:06 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* parse.y (assign_in_cond): warn for static content object asignments
diff --git a/vm.c b/vm.c
index c9a6866d6f..39efee27c9 100644
--- a/vm.c
+++ b/vm.c
@@ -1872,14 +1872,7 @@ vm_define_method(rb_thread_t *th, VALUE obj, ID id, VALUE iseqval,
     }
 
     if (is_singleton) {
-	if (FIXNUM_P(obj) || SYMBOL_P(obj) || CLASS_OF(obj) == rb_cFloat) {
-	    rb_raise(rb_eTypeError,
-		     "can't define singleton method \"%s\" for %s",
-		     rb_id2name(id), rb_obj_classname(obj));
-	}
-
-	rb_check_frozen(obj);
-	klass = rb_singleton_class(obj);
+	klass = rb_singleton_class(obj); /* class and frozen checked in this API */
 	noex = NOEX_PUBLIC;
     }