diff --git a/jedi/evaluate/imports.py b/jedi/evaluate/imports.py
index 78acc98c..25fd298f 100644
--- a/jedi/evaluate/imports.py
+++ b/jedi/evaluate/imports.py
@@ -11,6 +11,7 @@ correct implementation is delegated to _compatibility.
 This module also supports import autocompletion, which means to complete
 statements like ``from datetim`` (curser at the end would return ``datetime``).
 """
+import imp
 import os
 import pkgutil
 import sys
@@ -378,9 +379,14 @@ class _Importer(object):
         if is_package_directory or current_namespace[0]:
             # is a directory module
             if is_package_directory:
-                path = os.path.join(path, '__init__.py')
-                with open(path, 'rb') as f:
-                    source = f.read()
+                for suffix, _, _ in imp.get_suffixes():
+                    p = os.path.join(path, '__init__' + suffix)
+                    if os.path.exists(p):
+                        if suffix == '.py':
+                            with open(path, 'rb') as f:
+                                source = f.read()
+                        else:  # It's a binary!
+                            source = None
             else:
                 source = current_namespace[0].read()
                 current_namespace[0].close()
diff --git a/pytest.ini b/pytest.ini
index b89fa59c..3a066302 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -2,7 +2,7 @@
 addopts = --doctest-modules
 
 # Ignore broken files in blackbox test directories
-norecursedirs = .* docs completion refactor absolute_import namespace_package scripts extensions speed static_analysis not_in_sys_path buildout_project egg-link
+norecursedirs = .* docs completion refactor absolute_import namespace_package scripts extensions speed static_analysis not_in_sys_path buildout_project egg-link init_extension_module
 
 # Activate `clean_jedi_cache` fixture for all tests.  This should be
 # fine as long as we are using `clean_jedi_cache` as a session scoped
diff --git a/test/test_evaluate/test_extension.py b/test/test_evaluate/test_extension.py
index cf15b55c..5a4bc375 100644
--- a/test/test_evaluate/test_extension.py
+++ b/test/test_evaluate/test_extension.py
@@ -4,6 +4,7 @@ Test compiled module
 import os
 
 import jedi
+from ..helpers import cwd_at
 
 
 def test_completions():
@@ -29,3 +30,18 @@ def test_call_signatures_stdlib():
     sigs = s.call_signatures()
     assert len(sigs) == 1
     assert len(sigs[0].params) == 1
+
+
+@cwd_at('test/test_evaluate')
+def test_init_extension_module():
+    """
+    ``__init__`` extension modules are also packages and Jedi should understand
+    that.
+
+    Originally coming from #472.
+    """
+    s = jedi.Script('import init_extension_module as i\ni.', path='not_existing.py')
+    assert 'foo' in [c.name for c in s.completions()]
+
+    s = jedi.Script('from init_extension_module import foo\nfoo', path='not_existing.py')
+    assert ['foo'] == [c.name for c in s.completions()]