diff --git a/ChangeLog b/ChangeLog
index 23d090496b..e0a78c4805 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Sun Jun 17 22:23:53 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* dir.c (rb_file_directory_p): move documentation for Dir.exist? from
+	  file.c so that the proper description will be shown instead of the
+	  documentation of File.directory?.  [ruby-core:45685]
+
 Sun Jun 17 16:21:01 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* thread_win32.h (rb_thread_lock_t): make a union for USE_WIN32_MUTEX.
diff --git a/dir.c b/dir.c
index ac4b1c614b..ded9560528 100644
--- a/dir.c
+++ b/dir.c
@@ -2025,6 +2025,22 @@ dir_s_home(int argc, VALUE *argv, VALUE obj)
     return rb_home_dir(u, rb_str_new(0, 0));
 }
 
+#if 0
+/*
+ * call-seq:
+ *   Dir.exist?(file_name)   ->  true or false
+ *   Dir.exists?(file_name)   ->  true or false
+ *
+ * Returns <code>true</code> if the named file is a directory,
+ * <code>false</code> otherwise.
+ *
+ */
+VALUE
+rb_file_directory_p()
+{
+}
+#endif
+
 /*
  *  Objects of class <code>Dir</code> are directory streams representing
  *  directories in the underlying file system. They provide a variety of
@@ -2073,8 +2089,8 @@ Init_Dir(void)
 
     rb_define_singleton_method(rb_cDir,"glob", dir_s_glob, -1);
     rb_define_singleton_method(rb_cDir,"[]", dir_s_aref, -1);
-    rb_define_singleton_method(rb_cDir,"exist?", rb_file_directory_p, 1); /* in file.c */
-    rb_define_singleton_method(rb_cDir,"exists?", rb_file_directory_p, 1); /* in file.c */
+    rb_define_singleton_method(rb_cDir,"exist?", rb_file_directory_p, 1);
+    rb_define_singleton_method(rb_cDir,"exists?", rb_file_directory_p, 1);
 
     rb_define_singleton_method(rb_cFile,"fnmatch", file_s_fnmatch, -1);
     rb_define_singleton_method(rb_cFile,"fnmatch?", file_s_fnmatch, -1);
diff --git a/file.c b/file.c
index bf584c843a..1eca6c7fdc 100644
--- a/file.c
+++ b/file.c
@@ -1091,18 +1091,6 @@ access_internal(const char *path, int mode)
  *
  */
 
-/*
- * Document-method: exist?
- *
- * call-seq:
- *   Dir.exist?(file_name)   ->  true or false
- *   Dir.exists?(file_name)   ->  true or false
- *
- * Returns <code>true</code> if the named file is a directory,
- * <code>false</code> otherwise.
- *
- */
-
 /*
  * Document-method: directory?
  *