Based on the patch in GNOME #575544

Index: gnome-session-2.28.0/gnome-session/gsm-manager.c
===================================================================
--- gnome-session-2.28.0.orig/gnome-session/gsm-manager.c	2009-09-18 18:36:04.000000000 +0200
+++ gnome-session-2.28.0/gnome-session/gsm-manager.c	2009-10-24 12:43:56.861770100 +0200
@@ -68,6 +68,7 @@
 #define GSM_MANAGER_DBUS_NAME "org.gnome.SessionManager"
 
 #define GSM_MANAGER_PHASE_TIMEOUT 10 /* seconds */
+#define GSM_MANAGER_SAVE_SESSION_TIMEOUT 2
 
 #define GDM_FLEXISERVER_COMMAND "gdmflexiserver"
 #define GDM_FLEXISERVER_ARGS    "--startnew Standard"
@@ -1147,6 +1148,69 @@ query_end_session_complete (GsmManager *
 
 }
 
+static gboolean
+_client_request_save (GsmClient            *client,
+                      ClientEndSessionData *data)
+{
+        gboolean ret;
+        GError  *error;
+
+        error = NULL;
+        ret = gsm_client_request_save (client, data->flags, &error);
+        if (ret) {
+                g_debug ("GsmManager: adding client to query clients: %s", gsm_client_peek_id (client));
+                data->manager->priv->query_clients = g_slist_prepend (data->manager->priv->query_clients,
+                                                                      client);
+        } else if (error) {
+                g_debug ("GsmManager: unable to query client: %s", error->message);
+                g_error_free (error);
+        }
+
+        return FALSE;
+}
+
+static gboolean
+_client_request_save_helper (const char           *id,
+                             GsmClient            *client,
+                             ClientEndSessionData *data)
+{
+        return _client_request_save (client, data);
+}
+
+static void
+query_save_session_complete (GsmManager *manager)
+{
+        GError *error = NULL;
+
+        if (g_slist_length (manager->priv->next_query_clients) > 0) {
+                ClientEndSessionData data;
+
+                data.manager = manager;
+                data.flags = GSM_CLIENT_END_SESSION_FLAG_LAST;
+
+                g_slist_foreach (manager->priv->next_query_clients,
+                                 (GFunc)_client_request_save,
+                                 &data);
+
+                g_slist_free (manager->priv->next_query_clients);
+                manager->priv->next_query_clients = NULL;
+
+                return;
+        }
+
+        if (manager->priv->query_timeout_id > 0) {
+                g_source_remove (manager->priv->query_timeout_id);
+                manager->priv->query_timeout_id = 0;
+        }
+
+        gsm_session_save (manager->priv->clients, &error);
+
+        if (error) {
+                g_warning ("Error saving session: %s", error->message);
+                g_error_free (error);
+        }
+}
+
 static guint32
 generate_cookie (void)
 {
@@ -1221,6 +1285,21 @@ _on_query_end_session_timeout (GsmManage
         return FALSE;
 }
 
+static gboolean
+_on_query_save_session_timeout (GsmManager *manager)
+{
+        manager->priv->query_timeout_id = 0;
+
+        g_debug ("GsmManager: query to save session timed out");
+
+        g_slist_free (manager->priv->query_clients);
+        manager->priv->query_clients = NULL;
+
+        query_save_session_complete (manager);
+
+        return FALSE;
+}
+
 static void
 do_phase_query_end_session (GsmManager *manager)
 {
@@ -1857,13 +1936,32 @@ on_client_end_session_response (GsmClien
                                 const char *reason,
                                 GsmManager *manager)
 {
-        /* just ignore if received outside of shutdown */
-        if (manager->priv->phase < GSM_MANAGER_PHASE_QUERY_END_SESSION) {
+        /* just ignore if we are not yet running */
+        if (manager->priv->phase < GSM_MANAGER_PHASE_RUNNING) {
                 return;
         }
 
         g_debug ("GsmManager: Response from end session request: is-ok=%d do-last=%d cancel=%d reason=%s", is_ok, do_last, cancel, reason ? reason :"");
 
+        if (manager->priv->phase == GSM_MANAGER_PHASE_RUNNING) {
+                /* Ignore responses when no requests were sent */
+                if (manager->priv->query_clients == NULL) {
+                        return;
+                }
+
+                manager->priv->query_clients = g_slist_remove (manager->priv->query_clients, client);
+
+                if (do_last) {
+                        manager->priv->next_query_clients = g_slist_prepend (manager->priv->next_query_clients,
+                                                                             client);
+                }
+
+                if (manager->priv->query_clients == NULL) {
+                        query_save_session_complete (manager);
+                }
+                return;
+        }
+
         if (cancel) {
                 cancel_end_session (manager);
                 return;
@@ -1962,6 +2060,15 @@ on_xsmp_client_logout_request (GsmXSMPCl
 }
 
 static void
+on_xsmp_client_save_request (GsmXSMPClient *client,
+                             gboolean       show_dialog,
+                             GsmManager    *manager)
+{
+        g_debug ("GsmManager: save_request");
+        gsm_manager_save_session (manager, NULL);
+}
+
+static void
 on_store_client_added (GsmStore   *store,
                        const char *id,
                        GsmManager *manager)
@@ -1982,6 +2089,10 @@ on_store_client_added (GsmStore   *store
                                   "logout-request",
                                   G_CALLBACK (on_xsmp_client_logout_request),
                                   manager);
+		g_signal_connect (client,
+				  "save-request",
+				  G_CALLBACK (on_xsmp_client_save_request),
+				  manager);
         }
 
         g_signal_connect (client,
@@ -2939,6 +3050,41 @@ gsm_manager_shutdown (GsmManager *manage
 }
 
 gboolean
+gsm_manager_save_session (GsmManager *manager,
+                          GError     **error)
+{
+        ClientEndSessionData data;
+
+        g_debug ("GsmManager: SaveSession called");
+
+        g_return_val_if_fail (GSM_IS_MANAGER (manager), FALSE);
+
+        if (manager->priv->phase != GSM_MANAGER_PHASE_RUNNING) {
+                g_set_error (error,
+                             GSM_MANAGER_ERROR,
+                             GSM_MANAGER_ERROR_NOT_IN_RUNNING,
+                             "SaveSession interface is only available during the Running phase");
+                return FALSE;
+        }
+
+        data.manager = manager;
+        data.flags = 0;
+        gsm_store_foreach (manager->priv->clients,
+                           (GsmStoreFunc)_client_request_save_helper,
+                           &data);
+
+        if (manager->priv->query_clients) {
+                manager->priv->query_timeout_id = g_timeout_add_seconds (GSM_MANAGER_SAVE_SESSION_TIMEOUT,
+                                                                         (GSourceFunc)_on_query_save_session_timeout,
+                                                                         manager);
+                return TRUE;
+        } else {
+                g_debug ("GsmManager: Nothing to save");
+                return FALSE;
+        }
+}
+
+gboolean
 gsm_manager_can_shutdown (GsmManager *manager,
                           gboolean   *shutdown_available,
                           GError    **error)
Index: gnome-session-2.28.0/gnome-session/gsm-manager.h
===================================================================
--- gnome-session-2.28.0.orig/gnome-session/gsm-manager.h	2009-04-19 20:26:52.000000000 +0200
+++ gnome-session-2.28.0/gnome-session/gsm-manager.h	2009-10-24 12:43:56.861770100 +0200
@@ -152,6 +152,9 @@ gboolean            gsm_manager_is_inhib
 gboolean            gsm_manager_shutdown                       (GsmManager     *manager,
                                                                 GError        **error);
 
+gboolean            gsm_manager_save_session                   (GsmManager     *manager,
+                                                                GError        **error);
+
 gboolean            gsm_manager_can_shutdown                   (GsmManager     *manager,
                                                                 gboolean       *shutdown_available,
                                                                 GError        **error);
Index: gnome-session-2.28.0/gnome-session/gsm-xsmp-client.c
===================================================================
--- gnome-session-2.28.0.orig/gnome-session/gsm-xsmp-client.c	2009-07-29 02:36:08.000000000 +0200
+++ gnome-session-2.28.0/gnome-session/gsm-xsmp-client.c	2009-10-24 12:43:56.861770100 +0200
@@ -70,6 +70,7 @@ enum {
 enum {
         REGISTER_REQUEST,
         LOGOUT_REQUEST,
+	SAVE_REQUEST,
         LAST_SIGNAL
 };
 
@@ -523,6 +524,30 @@ xsmp_cancel_end_session (GsmClient *clie
         return TRUE;
 }
 
+static gboolean
+xsmp_request_save (GsmClient *client,
+                   guint      flags,
+                   GError   **error)
+{
+        GsmXSMPClient *xsmp = (GsmXSMPClient *) client;
+
+        g_debug ("GsmXSMPClient: xsmp_request_save ('%s')", xsmp->priv->description);
+
+        if (xsmp->priv->conn == NULL) {
+                g_set_error (error,
+                             GSM_CLIENT_ERROR,
+                             GSM_CLIENT_ERROR_NOT_REGISTERED,
+                             "Client is not registered");
+                return FALSE;
+        }
+
+        if (flags & GSM_CLIENT_END_SESSION_FLAG_LAST)
+                xsmp_save_yourself_phase2 (client);
+        else
+                do_save_yourself (xsmp, SmSaveLocal, FALSE);
+
+        return TRUE;
+}
 static char *
 get_desktop_file_path (GsmXSMPClient *client)
 {
@@ -993,6 +1018,7 @@ gsm_xsmp_client_class_init (GsmXSMPClien
         object_class->get_property         = gsm_xsmp_client_get_property;
         object_class->set_property         = gsm_xsmp_client_set_property;
 
+        client_class->impl_request_save           = xsmp_request_save;
         client_class->impl_save                   = xsmp_save;
         client_class->impl_stop                   = xsmp_stop;
         client_class->impl_query_end_session      = xsmp_query_end_session;
@@ -1023,6 +1049,17 @@ gsm_xsmp_client_class_init (GsmXSMPClien
                               G_TYPE_NONE,
                               1, G_TYPE_BOOLEAN);
 
+	signals[SAVE_REQUEST] =
+		g_signal_new ("save-request",
+                              G_OBJECT_CLASS_TYPE (object_class),
+                              G_SIGNAL_RUN_LAST,
+                              G_STRUCT_OFFSET (GsmXSMPClientClass, save_request),
+                              NULL,
+                              NULL,
+                              g_cclosure_marshal_VOID__BOOLEAN,
+                              G_TYPE_NONE,
+                              1, G_TYPE_BOOLEAN);
+
         g_object_class_install_property (object_class,
                                          PROP_ICE_CONNECTION,
                                          g_param_spec_pointer ("ice-connection",
Index: gnome-session-2.28.0/gnome-session/gsm-xsmp-client.h
===================================================================
--- gnome-session-2.28.0.orig/gnome-session/gsm-xsmp-client.h	2009-04-19 20:26:52.000000000 +0200
+++ gnome-session-2.28.0/gnome-session/gsm-xsmp-client.h	2009-10-24 12:43:56.861770100 +0200
@@ -54,7 +54,8 @@ struct _GsmXSMPClientClass
                                           char          **client_id);
         gboolean (*logout_request)       (GsmXSMPClient  *client,
                                           gboolean        prompt);
-
+	gboolean (*save_request)	 (GsmXSMPClient  *client,
+                                          gboolean        prompt);
 
         void     (*saved_state)          (GsmXSMPClient  *client);
 
Index: gnome-session-2.28.0/gnome-session/org.gnome.SessionManager.xml
===================================================================
--- gnome-session-2.28.0.orig/gnome-session/org.gnome.SessionManager.xml	2009-04-19 20:26:52.000000000 +0200
+++ gnome-session-2.28.0/gnome-session/org.gnome.SessionManager.xml	2009-10-24 12:43:56.865763345 +0200
@@ -256,6 +256,14 @@
       </doc:doc>
     </method>
 
+    <method name="SaveSession">
+      <doc:doc>
+	<doc:description>
+	  <doc:para>Request to save session</doc:para>
+	</doc:description>
+      </doc:doc>
+    </method>
+
     <method name="CanShutdown">
       <arg name="is_available" direction="out" type="b">
         <doc:doc>
Index: gnome-session-2.28.0/capplet/gsm-properties-dialog.c
===================================================================
--- gnome-session-2.28.0.orig/capplet/gsm-properties-dialog.c	2009-08-25 10:03:42.000000000 +0200
+++ gnome-session-2.28.0/capplet/gsm-properties-dialog.c	2009-10-24 13:21:57.910268989 +0200
@@ -35,6 +35,12 @@
 #include "gsm-util.h"
 #include "gsp-app.h"
 #include "gsp-app-manager.h"
+#include <dbus/dbus-glib.h>
+#include <dbus/dbus-glib-lowlevel.h>
+
+#define GSM_SERVICE_DBUS   "org.gnome.SessionManager"
+#define GSM_PATH_DBUS      "/org/gnome/SessionManager"
+#define GSM_INTERFACE_DBUS "org.gnome.SessionManager"
 
 #define GSM_PROPERTIES_DIALOG_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), GSM_TYPE_PROPERTIES_DIALOG, GsmPropertiesDialogPrivate))
 
@@ -50,6 +56,7 @@
 #define CAPPLET_DELETE_WIDGET_NAME        "session_properties_delete_button"
 #define CAPPLET_EDIT_WIDGET_NAME          "session_properties_edit_button"
 #define CAPPLET_SAVE_WIDGET_NAME          "session_properties_save_button"
+#define CAPPLET_SESSION_SAVED_WIDGET_NAME "session_properties_session_saved_label"
 #define CAPPLET_REMEMBER_WIDGET_NAME      "session_properties_remember_toggle"
 
 #define STARTUP_APP_ICON     "system-run"
@@ -493,10 +500,64 @@ on_autosave_value_toggled (GtkToggleButt
 }
 
 static void
+session_saved_message (GsmPropertiesDialog *dialog,
+                       const char *msg,
+                       gboolean is_error)
+{
+        GtkLabel *label;
+        gchar *markup;
+        label = GTK_LABEL (gtk_builder_get_object (dialog->priv->xml, CAPPLET_SESSION_SAVED_WIDGET_NAME));
+        if (is_error)
+                markup = g_markup_printf_escaped ("<span foreground=\"red\">%s</span>", msg);
+        else
+                markup = g_markup_escape_text (msg, -1);
+        gtk_label_set_markup (label, markup);
+        g_free (markup);
+}
+
+static void
+session_saved_cb (DBusGProxy *proxy,
+                  DBusGProxyCall *call_id,
+                  void *user_data)
+{
+        gboolean res;
+        GsmPropertiesDialog *dialog = user_data;
+
+        res = dbus_g_proxy_end_call (proxy, call_id, NULL, G_TYPE_INVALID);
+        if (res)
+                session_saved_message (dialog, _("Your session has been saved."), FALSE);
+        else
+                session_saved_message (dialog, _("Failed to save session"), TRUE);
+
+        g_object_unref (proxy);
+}
+
+static void
 on_save_session_clicked (GtkWidget           *widget,
                          GsmPropertiesDialog *dialog)
 {
-        g_debug ("Session saving is not implemented yet!");
+        DBusGConnection *conn;
+        DBusGProxy *proxy;
+        DBusGProxyCall *call;
+
+        conn = dbus_g_bus_get (DBUS_BUS_SESSION, NULL);
+        if (conn == NULL) {
+                session_saved_message (dialog, _("Could not connect to the session bus"), TRUE);
+                return;
+        }
+
+        proxy = dbus_g_proxy_new_for_name (conn, GSM_SERVICE_DBUS, GSM_PATH_DBUS, GSM_INTERFACE_DBUS);
+        if (proxy == NULL) {
+                session_saved_message (dialog, _("Could not connect to the session manager"), TRUE);
+                return;
+        }
+
+        call = dbus_g_proxy_begin_call (proxy, "SaveSession", session_saved_cb, dialog, NULL, G_TYPE_INVALID);
+        if (call == NULL) {
+                session_saved_message (dialog, _("Failed to save session"), TRUE);
+                g_object_unref (proxy);
+                return;
+        }
 }
 
 static void
Index: gnome-session-2.28.0/configure.in
===================================================================
--- gnome-session-2.28.0.orig/configure.in	2009-09-09 02:21:06.000000000 +0200
+++ gnome-session-2.28.0/configure.in	2009-10-24 12:46:15.021757805 +0200
@@ -59,6 +59,7 @@ PKG_CHECK_MODULES(GNOME_SESSION,
 PKG_CHECK_MODULES(SESSION_PROPERTIES,
         glib-2.0 >= $GLIB_REQUIRED
         gtk+-2.0 >= $GTK_REQUIRED
+        dbus-glib-1 >= $DBUS_GLIB_REQUIRED
 )
 
 PKG_CHECK_MODULES(SPLASH,
Index: gnome-session-2.28.0/gnome-session/gsm-client.h
===================================================================
--- gnome-session-2.28.0.orig/gnome-session/gsm-client.h	2009-04-19 20:26:52.000000000 +0200
+++ gnome-session-2.28.0/gnome-session/gsm-client.h	2009-10-24 12:43:56.873765479 +0200
@@ -92,6 +92,9 @@ struct _GsmClientClass
                                                               GError   **error);
         gboolean              (*impl_stop)                   (GsmClient *client,
                                                               GError   **error);
+        gboolean              (*impl_request_save)           (GsmClient *client,
+                                                              guint      flags,
+                                                              GError   **error);
         GKeyFile *            (*impl_save)                   (GsmClient *client,
                                                               GError   **error);
 };
@@ -137,6 +140,9 @@ gboolean              gsm_client_cancel_
 
 void                  gsm_client_disconnected               (GsmClient  *client);
 
+gboolean              gsm_client_request_save               (GsmClient  *client,
+                                                             guint       flags,
+                                                             GError    **error);
 GKeyFile             *gsm_client_save                       (GsmClient  *client,
                                                              GError    **error);
 /* exported to bus */
Index: gnome-session-2.28.0/gnome-session/gsm-dbus-client.c
===================================================================
--- gnome-session-2.28.0.orig/gnome-session/gsm-dbus-client.c	2009-04-19 20:26:52.000000000 +0200
+++ gnome-session-2.28.0/gnome-session/gsm-dbus-client.c	2009-10-24 12:43:56.873765479 +0200
@@ -413,6 +413,19 @@ gsm_dbus_client_finalize (GObject *objec
         G_OBJECT_CLASS (gsm_dbus_client_parent_class)->finalize (object);
 }
 
+static gboolean
+dbus_client_request_save (GsmClient *client,
+                          guint      flags,
+                          GError   **error)
+{
+        g_debug ("GsmDBusClient: sending save request to client with id %s",
+                 gsm_client_peek_id (client));
+
+        /* FIXME: The protocol does not support this */
+
+        return FALSE;
+}
+
 static GKeyFile *
 dbus_client_save (GsmClient *client,
                   GError   **error)
@@ -665,6 +678,7 @@ gsm_dbus_client_class_init (GsmDBusClien
         object_class->set_property         = gsm_dbus_client_set_property;
         object_class->dispose              = gsm_dbus_client_dispose;
 
+        client_class->impl_request_save           = dbus_client_request_save;
         client_class->impl_save                   = dbus_client_save;
         client_class->impl_stop                   = dbus_client_stop;
         client_class->impl_query_end_session      = dbus_client_query_end_session;
Index: gnome-session-2.28.0/gnome-session/gsm-client.c
===================================================================
--- gnome-session-2.28.0.orig/gnome-session/gsm-client.c	2009-04-19 20:26:52.000000000 +0200
+++ gnome-session-2.28.0/gnome-session/gsm-client.c	2009-10-24 12:43:56.877763612 +0200
@@ -510,6 +510,16 @@ gsm_client_disconnected (GsmClient *clie
         g_signal_emit (client, signals[DISCONNECTED], 0);
 }
 
+gboolean
+gsm_client_request_save (GsmClient *client,
+                         guint      flags,
+                         GError   **error)
+{
+        g_return_val_if_fail (GSM_IS_CLIENT (client), FALSE);
+
+        return GSM_CLIENT_GET_CLASS (client)->impl_request_save (client, flags, error);
+}
+
 GKeyFile *
 gsm_client_save (GsmClient *client,
                  GError   **error)
Index: gnome-session-2.28.0/data/session-properties.ui
===================================================================
--- gnome-session-2.28.0.orig/data/session-properties.ui	2009-10-24 12:55:01.946268673 +0200
+++ gnome-session-2.28.0/data/session-properties.ui	2009-10-24 12:54:11.638268279 +0200
@@ -148,6 +148,7 @@
             <property name="visible">True</property>
             <child>
               <object class="GtkButton" id="session_properties_save_button">
+                <property name="visible">True</property>
                 <property name="can_focus">True</property>
                 <property name="receives_default">True</property>
                 <child>
@@ -191,6 +192,17 @@
             <property name="position">1</property>
           </packing>
         </child>
+        <child>
+          <object class="GtkLabel" id="session_properties_session_saved_label">
+            <property name="visible">True</property>
+            <property name="wrap">True</property>
+          </object>
+          <packing>
+            <property name="expand">False</property>
+            <property name="fill">False</property>
+            <property name="position">2</property>
+          </packing>
+        </child>
       </object>
       <packing>
         <property name="position">1</property>
