Fixed a problem in temp file cleanup.

buildout.cfg

@@ -9,7 +9,7 @@ eggs = ZODB3
 initialization = 
   import os, tempfile, shutil, stat
   [[os.chmod(os.path.join(path, f), stat.S_IWUSR) for f in files]
-    for (path, dirs, files) in os.walk(os.getcwd())]
+    for (path, dirs, files) in os.walk('tmp')]
   if os.path.exists('tmp'): shutil.rmtree('tmp')
   os.mkdir('tmp')
   tempfile.tempdir = os.path.abspath('tmp')