diff --git a/matrix/server.py b/matrix/server.py
index a4e5145..e29feca 100644
--- a/matrix/server.py
+++ b/matrix/server.py
@@ -1328,7 +1328,7 @@ class MatrixServer(object):
         self.send(request)
 
     def confirm_sas(self, sas):
-        _, request = self.client.accept_short_auth_string(sas.transaction_id)
+        _, request = self.client.confirm_short_auth_string(sas.transaction_id)
         self.send(request)
 
         device = sas.other_olm_device