diff --git a/ChangeLog b/ChangeLog
index 68902b3962..e7376ba3aa 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,8 @@ Mon Jul  9 16:49:30 2001  WATANABE Hirofumi  <eban@ruby-lang.org>
 
 	* ext/extmk.rb.in: modify RM macro.
 
+	* lib/mkmf.rb: ditto.
+
 Sun Jul  8 20:52:02 2001  Akinori MUSHA  <knu@iDaemons.org>
 
 	* ruby.h: fix a wrong function name: rb_iglob() -> rb_globi().
diff --git a/lib/mkmf.rb b/lib/mkmf.rb
index 92d216a12d..fec789e4e8 100644
--- a/lib/mkmf.rb
+++ b/lib/mkmf.rb
@@ -53,8 +53,8 @@ def rm_f(*files)
     targets.concat Dir[file]
   end
   if not targets.empty?
-    File::chmod 0777, *targets
-    File::unlink *targets
+    File::chmod(0777, *targets)
+    File::unlink(*targets)
   end
 end
 
@@ -469,7 +469,7 @@ TARGET = #{target}
 DLLIB = $(TARGET).#{CONFIG["DLEXT"]}
 
 RUBY = #{CONFIG["ruby_install_name"]}
-RM = $(RUBY) -r ftools -e 'File::rm_f(*Dir[ARGV.join(" ")])'
+RM = $(RUBY) -rftools -e 'File::rm_f(*ARGV.map{|x|Dir[x]}.flatten.uniq)'
 
 EXEEXT = #{CONFIG["EXEEXT"]}