diff --git a/pyngus/__init__.py b/pyngus/__init__.py
index a224257..50150e4 100644
--- a/pyngus/__init__.py
+++ b/pyngus/__init__.py
@@ -23,4 +23,4 @@ from pyngus.link import SenderLink, SenderEventHandler
 from pyngus.sockets import read_socket_input
 from pyngus.sockets import write_socket_output
 
-VERSION = (1, 3, 1)  # major, minor, fix
+VERSION = (1, 4, 0)  # major, minor, fix
diff --git a/setup.py b/setup.py
index fff9247..dc84c7a 100644
--- a/setup.py
+++ b/setup.py
@@ -19,7 +19,7 @@
 
 from setuptools import setup
 
-_VERSION = "1.3.1"   # NOTE: update __init__.py too!
+_VERSION = "1.4.0rc1"   # NOTE: update __init__.py too!
 
 # I hack, therefore I am (productive) Some distros (which will not be named)
 # don't use setup.py to install the proton python module.  In this case, pip
diff --git a/tests/unit_tests/common.py b/tests/unit_tests/common.py
index 31140be..99b1c7b 100644
--- a/tests/unit_tests/common.py
+++ b/tests/unit_tests/common.py
@@ -20,7 +20,13 @@
 import gc
 import time
 
-from proton import VERSION_MAJOR, VERSION_MINOR
+try:
+    from proton import VERSION_MAJOR, VERSION_MINOR
+except ImportError:
+    # older proton did not export version info
+    VERSION_MAJOR = 0
+    VERSION_MINOR = 0
+
 import pyngus
 
 
diff --git a/tox.ini b/tox.ini
index 4c74359..1091e42 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,7 +9,8 @@ deps = -r{toxinidir}/test-requirements.txt
 commands = {toxinidir}/tests/test-runner
 
 [testenv:pep8]
-commands = flake8 pyngus examples tests setup.py
+commands = flake8 pyngus examples tests
+           flake8 --ignore F401 setup.py
 
 [flake8]
 show-source = True