diff --git a/ChangeLog b/ChangeLog
index c127a142d7..104f784fa7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Mon Feb 20 22:30:17 2006  Tanaka Akira  <akr@m17n.org>
+
+	* mkconfig.rb: alias Config to RbConfig for compatibility.
+
 Mon Feb 20 18:21:41 2006  Tanaka Akira  <akr@m17n.org>
 
 	* io.c (rb_io_reopen): flush before reopening a file.
diff --git a/mkconfig.rb b/mkconfig.rb
index 29139c5716..02e91ab339 100644
--- a/mkconfig.rb
+++ b/mkconfig.rb
@@ -137,6 +137,7 @@ print <<EOS
     RbConfig::expand(val)
   end
 end
+Config = RbConfig # compatibility for ruby-1.8 and older.
 CROSS_COMPILING = nil unless defined? CROSS_COMPILING
 EOS