diff --git a/.travis.yml b/.travis.yml
index b6b18552..55b03143 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,6 +4,7 @@ env:
     - TOXENV=py27
     - TOXENV=py32
     - TOXENV=py33
+    - TOXENV=py34
     - TOXENV=pypy
     - TOXENV=cov
     - TOXENV=sith
@@ -14,6 +15,12 @@ matrix:
         - env: TOXENV=pypy
 install:
     - pip install --quiet --use-mirrors tox
+    # install python 3.4 from PPA since Travis does not have python 3.4 yet
+    - if [ "$TOXENV" = "py34" ]; then
+        sudo apt-add-repository -y ppa:fkrull/deadsnakes;
+        sudo apt-get update;
+        sudo apt-get install python3.4;
+      fi
 script:
     - tox
 after_script:
diff --git a/jedi/_compatibility.py b/jedi/_compatibility.py
index a862b74b..fdc11b6d 100644
--- a/jedi/_compatibility.py
+++ b/jedi/_compatibility.py
@@ -31,7 +31,8 @@ def find_module_py33(string, path=None):
             module_file = None
         else:
             module_path = loader.get_filename(string)
-            mode = 'rb' if module_path.endswith(".pyc") else 'r'
+            module_ext = os.path.splitext(module_path)[1]
+            mode = 'rb' if module_ext in ['.pyc', '.so', '.pyd'] else 'r'
             module_file = open(module_path, mode)
     except AttributeError:
         # ExtensionLoader has not attribute get_filename, instead it has a
diff --git a/tox.ini b/tox.ini
index d346be97..e6592223 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py26, py27, py32, py33
+envlist = py26, py27, py32, py33, py34
 [testenv]
 deps =
     https://bitbucket.org/hpk42/pytest/get/c4f58165e0d4.zip