--- xulrunner-27.0/mozilla/python/mozbuild/mozbuild/virtualenv.py~	2013-05-11 21:19:23.000000000 +0200
+++ xulrunner-27.0/mozilla/python/mozbuild/mozbuild/virtualenv.py	2013-05-14 22:51:32.136719267 +0200
@@ -37,8 +37,7 @@
     @property
     def virtualenv_script_path(self):
         """Path to virtualenv's own populator script."""
-        return os.path.join(self.topsrcdir, 'python', 'virtualenv',
-            'virtualenv.py')
+        return '/usr/bin/virtualenv'
 
     @property
     def python_path(self):