diff -r 9fb4b2c19bd8 -r 9bd54c35af97 tests/run-tests.py
--- a/tests/run-tests.py	Mon Jan 21 19:40:15 2013 +0100
+++ b/tests/run-tests.py	Tue Jan 29 20:03:51 2013 +0100
@@ -1252,7 +1252,7 @@
     os.environ['no_proxy'] = ''
     os.environ['NO_PROXY'] = ''
     os.environ['TERM'] = 'xterm'
-    os.environ['PYTHONHASHSEED'] = 'random'
+    os.environ['PYTHONHASHSEED'] = os.environ.get('PYTHONHASHSEED', 'random')
 
     # unset env related to hooks
     for k in os.environ.keys():