diff --git a/ChangeLog b/ChangeLog
index 4870008997..fa7f99fb4e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Fri Jan 11 09:23:31 2008  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* encoding (set_base_encoding): must use rb_enc_dummy_p.
+
 Fri Jan 11 06:13:14 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* encoding.c (rb_to_encoding_index, rb_to_encoding): disallow nil.
diff --git a/encoding.c b/encoding.c
index ec8303cfeb..4f719dbcd3 100644
--- a/encoding.c
+++ b/encoding.c
@@ -205,7 +205,7 @@ set_base_encoding(int index, rb_encoding *base)
     VALUE enc = rb_enc_from_encoding(enc_table[index].enc);
 
     rb_ivar_set(enc, id_base_encoding, rb_enc_from_encoding(base));
-    if (ENC_DUMMY_P(base)) FL_SET(enc, ENC_DUMMY);
+    if (rb_enc_dummy_p(base)) FL_SET(enc, ENC_DUMMY);
     return enc;
 }