diff --git a/ceilometer/api/app.py b/ceilometer/api/app.py
index 6db7649e6..8ffe092f8 100644
--- a/ceilometer/api/app.py
+++ b/ceilometer/api/app.py
@@ -77,6 +77,7 @@ def setup_app(pecan_config=None, extra_hooks=None):
         force_canonical=getattr(pecan_config.app, 'force_canonical', True),
         hooks=app_hooks,
         wrap_app=middleware.ParsableErrorMiddleware,
+        guess_content_type_from_ext=False
     )
 
     if pecan_config.app.enable_acl:
diff --git a/tests/api/v2/test_app.py b/tests/api/v2/test_app.py
index d829d4775..8033891e2 100644
--- a/tests/api/v2/test_app.py
+++ b/tests/api/v2/test_app.py
@@ -65,6 +65,15 @@ class TestApp(base.TestCase):
         os.unlink(tmpfile)
 
 
+class TestPecanApp(FunctionalTest):
+    database_connection = tests_db.MongoDBFakeConnectionUrl()
+
+    def test_pecan_extension_guessing_unset(self):
+        # check Pecan does not assume .jpg is an extension
+        response = self.app.get(self.PATH_PREFIX + '/meters/meter.jpg')
+        self.assertEqual(response.content_type, 'application/json')
+
+
 class TestApiMiddleware(FunctionalTest):
 
     # This doesn't really matter