diff --git a/ChangeLog b/ChangeLog
index d8fc118e2c..7cb55436ae 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Tue Jan 15 14:44:53 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* encoding.c (rb_locale_charmap): use ASCII-8BIT in miniruby.
+
 Tue Jan 15 13:54:41 2008  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* {bcc32,win32}/Makefile.sub (RUNRUBY): need to set archdir when
diff --git a/encoding.c b/encoding.c
index 46853964e1..d76e8edfb4 100644
--- a/encoding.c
+++ b/encoding.c
@@ -944,7 +944,7 @@ VALUE
 rb_locale_charmap(VALUE klass)
 {
 #if defined NO_LOCALE_CHARMAP
-    return Qnil;
+    return rb_str_new2("ASCII-8BIT");
 #elif defined HAVE_LANGINFO_H
     char *codeset;
     codeset = nl_langinfo(CODESET);