diff --git a/mitogen/ssh.py b/mitogen/ssh.py
index c15417d0..9ca923a1 100644
--- a/mitogen/ssh.py
+++ b/mitogen/ssh.py
@@ -57,6 +57,7 @@ class Stream(mitogen.parent.Stream):
     identity_file = None
     password = None
     port = None
+    ssh_args = None
 
     def construct(self, hostname, username=None, ssh_path=None, port=None,
                   check_host_keys=True, password=None, identity_file=None,