diff --git a/gio/gdbusauth.c b/gio/gdbusauth.c
index eadecb50d..671036805 100644
--- a/gio/gdbusauth.c
+++ b/gio/gdbusauth.c
@@ -577,8 +577,8 @@ _g_dbus_auth_run_client (GDBusAuth     *auth,
   ClientState state;
   GDBusCapabilityFlags negotiated_capabilities;
 
-  g_return_val_if_fail ((connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT), NULL);
-  g_return_val_if_fail (!(connection->flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER), NULL);
+  g_return_val_if_fail ((conn_flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT), NULL);
+  g_return_val_if_fail (!(conn_flags & G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER), NULL);
 
   debug_print ("CLIENT: initiating");
 
diff --git a/gio/gdbusauthmechanism.c b/gio/gdbusauthmechanism.c
index 38d7210e5..6e494dbd9 100644
--- a/gio/gdbusauthmechanism.c
+++ b/gio/gdbusauthmechanism.c
@@ -301,11 +301,13 @@ _g_dbus_auth_mechanism_client_get_state (GDBusAuthMechanism *mechanism)
 }
 
 gchar *
-_g_dbus_auth_mechanism_client_initiate (GDBusAuthMechanism *mechanism,
-                                        gsize              *out_initial_response_len)
+_g_dbus_auth_mechanism_client_initiate (GDBusAuthMechanism   *mechanism,
+                                        GDBusConnectionFlags  conn_flags,
+                                        gsize                *out_initial_response_len)
 {
   g_return_val_if_fail (G_IS_DBUS_AUTH_MECHANISM (mechanism), NULL);
   return G_DBUS_AUTH_MECHANISM_GET_CLASS (mechanism)->client_initiate (mechanism,
+                                                                       conn_flags,
                                                                        out_initial_response_len);
 }
 
diff --git a/gio/gdbusauthmechanismsha1.c b/gio/gdbusauthmechanismsha1.c
index a11c9f38d..fb6488a2a 100644
--- a/gio/gdbusauthmechanismsha1.c
+++ b/gio/gdbusauthmechanismsha1.c
@@ -119,6 +119,7 @@ static gchar                   *mechanism_server_get_reject_reason  (GDBusAuthMe
 static void                     mechanism_server_shutdown           (GDBusAuthMechanism   *mechanism);
 static GDBusAuthMechanismState  mechanism_client_get_state          (GDBusAuthMechanism   *mechanism);
 static gchar                   *mechanism_client_initiate           (GDBusAuthMechanism   *mechanism,
+                                                                     GDBusConnectionFlags  conn_flags,
                                                                      gsize                *out_initial_response_len);
 static void                     mechanism_client_data_receive       (GDBusAuthMechanism   *mechanism,
                                                                      const gchar          *data,
@@ -1160,6 +1161,7 @@ mechanism_client_get_state (GDBusAuthMechanism   *mechanism)
 
 static gchar *
 mechanism_client_initiate (GDBusAuthMechanism   *mechanism,
+                           GDBusConnectionFlags  conn_flags,
                            gsize                *out_initial_response_len)
 {
   GDBusAuthMechanismSha1 *m = G_DBUS_AUTH_MECHANISM_SHA1 (mechanism);
diff --git a/gio/gdbusconnection.c b/gio/gdbusconnection.c
index 454f216bd..663cd95ab 100644
--- a/gio/gdbusconnection.c
+++ b/gio/gdbusconnection.c
@@ -7369,6 +7369,9 @@ get_uninitialized_connection (GBusType       bus_type,
       ret = g_object_new (G_TYPE_DBUS_CONNECTION,
                           "address", address,
                           "flags", G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT |
+#ifdef __linux__
+                                   G_DBUS_CONNECTION_FLAGS_CROSS_NAMESPACE |
+#endif
                                    G_DBUS_CONNECTION_FLAGS_MESSAGE_BUS_CONNECTION,
                           "exit-on-close", TRUE,
                           NULL);
diff --git a/gio/tests/gdbus-connection.c b/gio/tests/gdbus-connection.c
index 61ca5c4b7..d04dd0446 100644
--- a/gio/tests/gdbus-connection.c
+++ b/gio/tests/gdbus-connection.c
@@ -1234,6 +1234,9 @@ test_connection_basic (void)
                  flags == G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING);
 
   connection_flags = g_dbus_connection_get_flags (connection);
+  /* Ignore G_DBUS_CONNECTION_FLAGS_CROSS_NAMESPACE, it's an
+   * implementation detail whether we set it */
+  connection_flags &= ~G_DBUS_CONNECTION_FLAGS_CROSS_NAMESPACE;
   g_assert_cmpint (connection_flags, ==,
                    G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT |
                    G_DBUS_CONNECTION_FLAGS_MESSAGE_BUS_CONNECTION);