diff --git a/MANIFEST.in b/MANIFEST.in
index 185e57646a4..fbda541d22c 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -32,3 +32,5 @@ recursive-include django/contrib/gis/tests/geogapp/fixtures *
 recursive-include django/contrib/gis/tests/relatedapp/fixtures *
 recursive-include django/contrib/sitemaps/templates *
 recursive-include django/contrib/sitemaps/tests/templates *
+recursive-exclude * __pycache__
+recursive-exclude * *.py[co]
diff --git a/django/core/management/templates.py b/django/core/management/templates.py
index aa65593e9cf..d34a0deb7ec 100644
--- a/django/core/management/templates.py
+++ b/django/core/management/templates.py
@@ -138,7 +138,7 @@ class TemplateCommand(BaseCommand):
                     os.mkdir(target_dir)
 
             for dirname in dirs[:]:
-                if dirname.startswith('.'):
+                if dirname.startswith('.') or dirname == '__pycache__':
                     dirs.remove(dirname)
 
             for filename in files:
diff --git a/django/db/utils.py b/django/db/utils.py
index 0ce09bab70e..b889cdf9ade 100644
--- a/django/db/utils.py
+++ b/django/db/utils.py
@@ -30,7 +30,7 @@ def load_backend(backend_name):
         try:
             available_backends = [f for f in os.listdir(backend_dir)
                     if os.path.isdir(os.path.join(backend_dir, f))
-                    and not f.startswith('.')]
+                    and not (f.startswith('.') or f == '__pycache__')]
         except EnvironmentError:
             available_backends = []
         full_notation = backend_name.startswith('django.db.backends.')
diff --git a/django/template/defaultfilters.py b/django/template/defaultfilters.py
index 1bfb6270239..e15440f90ee 100644
--- a/django/template/defaultfilters.py
+++ b/django/template/defaultfilters.py
@@ -96,7 +96,7 @@ def fix_ampersands_filter(value):
 # Values for testing floatformat input against infinity and NaN representations,
 # which differ across platforms and Python versions.  Some (i.e. old Windows
 # ones) are not recognized by Decimal but we want to return them unchanged vs.
-# returning an empty string as we do for completley invalid input.  Note these
+# returning an empty string as we do for completely invalid input.  Note these
 # need to be built up from values that are not inf/nan, since inf/nan values do
 # not reload properly from .pyc files on Windows prior to some level of Python 2.5
 # (see Python Issue757815 and Issue1080440).
diff --git a/setup.py b/setup.py
index 165c5e9f735..333d57ac70f 100644
--- a/setup.py
+++ b/setup.py
@@ -67,9 +67,10 @@ if root_dir != '':
 django_dir = 'django'
 
 for dirpath, dirnames, filenames in os.walk(django_dir):
-    # Ignore dirnames that start with '.'
+    # Ignore PEP 3147 cache dirs and those whose names start with '.'
     for i, dirname in enumerate(dirnames):
-        if dirname.startswith('.'): del dirnames[i]
+        if dirname.startswith('.') or dirname == '__pycache__':
+            del dirnames[i]
     if '__init__.py' in filenames:
         packages.append('.'.join(fullsplit(dirpath)))
     elif filenames: