diff --git a/Formula/libdvdcss.rb b/Formula/libdvdcss.rb
index a9701e25a2..7876f4a105 100644
--- a/Formula/libdvdcss.rb
+++ b/Formula/libdvdcss.rb
@@ -4,10 +4,11 @@ class Libdvdcss < Formula
   homepage 'http://www.videolan.org/developers/libdvdcss.html'
   url 'http://download.videolan.org/pub/libdvdcss/1.2.11/libdvdcss-1.2.11.tar.bz2'
   sha1 '55d75d603071aa4bbcd7a7dcfa63c52dd0e8a104'
+
   head 'svn://svn.videolan.org/libdvdcss/trunk'
 
   def install
-    system "./bootstrap" if ARGV.build_head?
+    system "./bootstrap" if build.head?
     system "./configure", "--prefix=#{prefix}", "--disable-debug", "--disable-dependency-tracking"
     system "make install"
   end