diff --git a/ChangeLog b/ChangeLog
index 94d5e0c5e4..9eaf3b7623 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Wed Jan  9 22:03:26 2008  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* encoding.c (rb_enc_replicate): replica of dummy is a dummy.
+
 Wed Jan  9 20:35:42 2008  GOTOU Yuuzou  <gotoyuzo@notwork.org>
 
 	* lib/webrick/httprequest.rb: supprt X-Forwarded-* header fields.
diff --git a/encoding.c b/encoding.c
index fc7fa37e24..422744478e 100644
--- a/encoding.c
+++ b/encoding.c
@@ -207,6 +207,7 @@ 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);
     return enc;
 }