diff --git a/synapse/storage/e2e_room_keys.py b/synapse/storage/e2e_room_keys.py
index 3c720f3b3e..e4d56b7c37 100644
--- a/synapse/storage/e2e_room_keys.py
+++ b/synapse/storage/e2e_room_keys.py
@@ -207,6 +207,7 @@ class EndToEndRoomKeyStore(SQLBaseStore):
                 this_version = version
 
             return self._simple_select_one_txn(
+                txn,
                 table="e2e_room_keys_versions",
                 keyvalues={
                     "user_id": user_id,
@@ -243,9 +244,9 @@ class EndToEndRoomKeyStore(SQLBaseStore):
             )
             current_version = txn.fetchone()[0]
             if current_version is None:
-                current_version = 0
+                current_version = '0'
 
-            new_version = current_version + 1
+            new_version = str(int(current_version) + 1)
 
             self._simple_insert_txn(
                 txn,
diff --git a/synapse/storage/schema/delta/46/e2e_room_keys.sql b/synapse/storage/schema/delta/46/e2e_room_keys.sql
index 16499ac34c..4531fd56ee 100644
--- a/synapse/storage/schema/delta/46/e2e_room_keys.sql
+++ b/synapse/storage/schema/delta/46/e2e_room_keys.sql
@@ -35,4 +35,4 @@ CREATE TABLE e2e_room_keys_versions (
     auth_data TEXT NOT NULL
 );
 
-CREATE UNIQUE INDEX e2e_room_keys_versions_user_idx ON e2e_room_keys_versions(user_id);
+CREATE UNIQUE INDEX e2e_room_keys_versions_idx ON e2e_room_keys_versions(user_id, version);
diff --git a/tests/handlers/test_e2e_room_keys.py b/tests/handlers/test_e2e_room_keys.py
index 9d3bef6db2..6f4b3a147a 100644
--- a/tests/handlers/test_e2e_room_keys.py
+++ b/tests/handlers/test_e2e_room_keys.py
@@ -37,7 +37,7 @@ class E2eRoomKeysHandlerTestCase(unittest.TestCase):
             handlers=None,
             replication_layer=mock.Mock(),
         )
-        self.handler = synapse.handlers.e2e_keys.E2eRoomKeysHandler(self.hs)
+        self.handler = synapse.handlers.e2e_room_keys.E2eRoomKeysHandler(self.hs)
 
 
     @defer.inlineCallbacks
@@ -46,6 +46,7 @@ class E2eRoomKeysHandlerTestCase(unittest.TestCase):
         if there is no version.
         """
         local_user = "@boris:" + self.hs.hostname
+        res = None
         try:
             res = yield self.handler.get_version_info(local_user);
         except errors.SynapseError as e:
@@ -58,6 +59,7 @@ class E2eRoomKeysHandlerTestCase(unittest.TestCase):
         if it doesn't exist.
         """
         local_user = "@boris:" + self.hs.hostname
+        res = None
         try:
             res = yield self.handler.get_version_info(local_user, "mrflibble");
         except errors.SynapseError as e:
@@ -69,7 +71,7 @@ class E2eRoomKeysHandlerTestCase(unittest.TestCase):
         """Check that we can create and then retrieve versions.
         """
         local_user = "@boris:" + self.hs.hostname
-        res = yield self.handler.create_version(user_id, {
+        res = yield self.handler.create_version(local_user, {
             "algorithm": "m.megolm_backup.v1",
             "auth_data": "first_version_auth_data",
         });
@@ -92,7 +94,7 @@ class E2eRoomKeysHandlerTestCase(unittest.TestCase):
         });
 
         # upload a new one...
-        res = yield self.handler.create_version(user_id, {
+        res = yield self.handler.create_version(local_user, {
             "algorithm": "m.megolm_backup.v1",
             "auth_data": "second_version_auth_data",
         });
@@ -111,7 +113,7 @@ class E2eRoomKeysHandlerTestCase(unittest.TestCase):
         """Check that we can create and then delete versions.
         """
         local_user = "@boris:" + self.hs.hostname
-        res = yield self.handler.create_version(user_id, {
+        res = yield self.handler.create_version(local_user, {
             "algorithm": "m.megolm_backup.v1",
             "auth_data": "first_version_auth_data",
         });
@@ -121,21 +123,22 @@ class E2eRoomKeysHandlerTestCase(unittest.TestCase):
         yield self.handler.delete_version(local_user, "1");
 
         # check that it's gone
+        res = None        
         try:
             res = yield self.handler.get_version_info(local_user, "1");
         except errors.SynapseError as e:
             self.assertEqual(e.code, 404);
-        self.assertEqual(res, None);        
+        self.assertEqual(res, None);
 
 
     @defer.inlineCallbacks
     def test_get_room_keys(self):
-        pass
+        yield None
 
     @defer.inlineCallbacks
     def test_upload_room_keys(self):
-        pass
+        yield None
 
     @defer.inlineCallbacks
     def test_delete_room_keys(self):
-        pass
+        yield None