diff --git a/ChangeLog b/ChangeLog
index 5f57f88490..8af72c40f2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Tue Jun 10 18:12:17 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* ext/extmk.rb: negate default of --without-ext.
+
 Tue Jun 10 17:01:58 2008  wanabe  <s.wanabe@gmail.com>
 
 	* util.c (ruby_strtod): ruby_strtod don't allow a trailing
diff --git a/ext/extmk.rb b/ext/extmk.rb
index 64746552c1..78707d7e9d 100644
--- a/ext/extmk.rb
+++ b/ext/extmk.rb
@@ -408,13 +408,15 @@ if $extension
 else
   withes, withouts = %w[--with --without].collect {|w|
     if not (w = %w[-extensions -ext].collect {|opt|arg_config(w+opt)}).any?
-      proc {false}
+      nil
     elsif (w = w.grep(String)).empty?
       proc {true}
     else
       proc {|c1| w.collect {|opt| opt.split(/,/)}.flatten.any?(&c1)}
     end
   }
+  withes ||= proc {false}
+  withouts ||= proc {true}
   cond = proc {|ext|
     cond1 = proc {|n| File.fnmatch(n, ext, File::FNM_PATHNAME)}
     withes.call(cond1) or !withouts.call(cond1)