1 files changed, 3 insertions, 2 deletions
diff --git a/tox.ini b/tox.ini
index 6c94c95d..e9c55452 100644
--- a/tox.ini
+++ b/tox.ini
@@ -22,10 +22,10 @@ commands =
     # Build the C extension and test with the CTracer
     {envpython} setup.py --quiet build_ext --inplace
     {envpython} igor.py test_with_tracer c {posargs}
-passenv = *
+
 deps =
     nose
-    mock
+    mock==1.0.1
     PyContracts
     py26: unittest2
     py26,py27: gevent
@@ -36,6 +36,7 @@ setenv =
     pypy24,pypy26,pypy3_24: COVERAGE_NO_EXTENSION=no C extensions under PyPy
 
 usedevelop = True
+passenv = *
 
 [testenv:pypy24]
 basepython = pypy2.4