diff --git a/ChangeLog b/ChangeLog
index 1682cd231d..13e9326b90 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat Nov 22 18:24:24 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* file.c (rb_file_world_writable_p): should return nil for non
+	  world-writable files.
+
 Sat Nov 22 10:31:25 2008  Hidetoshi NAGAI  <nagai@ai.kyutech.ac.jp>
 
 	* ext/tk/lib/tkextlib/blt.rb, ext/tk/lib/tkextlib/blt/vector.rb: 
diff --git a/file.c b/file.c
index 21f74f0129..aa814a5c76 100644
--- a/file.c
+++ b/file.c
@@ -1299,7 +1299,7 @@ rb_file_world_writable_p(VALUE obj, VALUE fname)
 #ifdef S_IWOTH
     struct stat st;
 
-    if (rb_stat(fname, &st) < 0) return Qfalse;
+    if (rb_stat(fname, &st) < 0) return Qnil;
     if ((st.st_mode & (S_IWOTH)) == S_IWOTH) {
 	return UINT2NUM(st.st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
     }