diff --git a/cinder/scheduler/rpcapi.py b/cinder/scheduler/rpcapi.py
index 2b128bdc9..602c11097 100644
--- a/cinder/scheduler/rpcapi.py
+++ b/cinder/scheduler/rpcapi.py
@@ -112,6 +112,10 @@ class SchedulerAPI(rpc.RPCAPI):
             # Send request_spec as dict
             version = '2.0'
             msg_args['request_spec'] = jsonutils.to_primitive(request_spec)
+            # NOTE(dulek): This is to keep supporting Mitaka's scheduler which
+            # expects a dictionary when creating a typeless volume.
+            if msg_args['request_spec'].get('volume_type') is None:
+                msg_args['request_spec']['volume_type'] = {}
 
         cctxt = self.client.prepare(version=version)
         return cctxt.cast(ctxt, 'create_volume', **msg_args)
diff --git a/cinder/tests/unit/scheduler/test_rpcapi.py b/cinder/tests/unit/scheduler/test_rpcapi.py
index 040d70cf4..dc73da7d2 100644
--- a/cinder/tests/unit/scheduler/test_rpcapi.py
+++ b/cinder/tests/unit/scheduler/test_rpcapi.py
@@ -109,7 +109,7 @@ class SchedulerRpcAPITestCase(test.TestCase):
                                  volume_id='volume_id',
                                  snapshot_id='snapshot_id',
                                  image_id='image_id',
-                                 request_spec='fake_request_spec',
+                                 request_spec={'volume_type': {}},
                                  filter_properties='filter_properties',
                                  volume='volume',
                                  version='2.0')