diff --git a/ChangeLog b/ChangeLog
index 6b82cbef1f..ee70c2f071 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Wed Mar 19 14:08:47 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* encoding.c (enc_check_encoding): should not load autoloaded encoding
+	  directly, instead use rb_enc_find_index() which deal with alias and
+	  replica.  [ruby-core:15957]
+
 Wed Mar 19 11:49:47 2008  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* regint.h (include): include ruby.h instead of defines.h and config.h.
diff --git a/encoding.c b/encoding.c
index c7881a8eda..9759da79a4 100644
--- a/encoding.c
+++ b/encoding.c
@@ -108,7 +108,7 @@ enc_check_encoding(VALUE obj)
     if (rb_enc_from_index(index) != enc)
 	return -1;
     if (enc_autoload_p(enc)) {
-	index = load_encoding(enc->name);
+	index = rb_enc_find_index(enc->name);
     }
     return index;
 }