diff --git a/tox.ini b/tox.ini
index fab61fc..2687bba 100644
--- a/tox.ini
+++ b/tox.ini
@@ -10,7 +10,8 @@ install_command =
 setenv = VIRTUAL_ENV={envdir}
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
-commands = python setup.py test --slowest --testr-args='{posargs}'
+commands = rm -f .testrepository/times.dbm
+           python setup.py test --slowest --testr-args='{posargs}'
 
 [testenv:pep8]
 commands = flake8