diff --git a/synapse/handlers/identity.py b/synapse/handlers/identity.py
index 6200e10775..c1095708a0 100644
--- a/synapse/handlers/identity.py
+++ b/synapse/handlers/identity.py
@@ -44,7 +44,7 @@ class IdentityHandler(BaseHandler):
         http_client = SimpleHttpClient(self.hs)
         # XXX: make this configurable!
         # trustedIdServers = ['matrix.org', 'localhost:8090']
-        trustedIdServers = ['matrix.org']
+        trustedIdServers = ['matrix.org', 'vector.im']
 
         if 'id_server' in creds:
             id_server = creds['id_server']
diff --git a/synapse/rest/client/v2_alpha/register.py b/synapse/rest/client/v2_alpha/register.py
index cf54e1dacf..b5926f9ca6 100644
--- a/synapse/rest/client/v2_alpha/register.py
+++ b/synapse/rest/client/v2_alpha/register.py
@@ -102,7 +102,8 @@ class RegisterRestServlet(RestServlet):
         if self.hs.config.disable_registration:
             raise SynapseError(403, "Registration has been disabled")
 
-        yield self.registration_handler.check_username(desired_username)
+        if desired_username is not None:
+            yield self.registration_handler.check_username(desired_username)
 
         if self.hs.config.enable_registration_captcha:
             flows = [