diff -uNr lxsession-0.4.6.1.orig/lxsession-logout/dbus-interface.c lxsession-0.4.6.1/lxsession-logout/dbus-interface.c
--- lxsession-0.4.6.1.orig/lxsession-logout/dbus-interface.c	2011-07-27 21:26:36.000000000 +0200
+++ lxsession-0.4.6.1/lxsession-logout/dbus-interface.c	2012-12-22 14:28:38.647031221 +0100
@@ -51,13 +51,20 @@
 char * dbus_HAL_Reboot(void);
 char * dbus_HAL_Suspend(void);
 char * dbus_HAL_Hibernate(void);
+gboolean dbus_logind_CanPowerOff(void);
+gboolean dbus_logind_CanReboot(void);
+gboolean dbus_logind_CanSuspend(void);
+gboolean dbus_logind_CanHibernate(void);
+char * dbus_logind_PowerOff(void);
+char * dbus_logind_Reboot(void);
+char * dbus_logind_Suspend(void);
+char * dbus_logind_Hibernate(void);
+char * dbus_LXDE_Logout(void);
 /* End FORWARDS */
 
 /* Connect to the system bus.  Once a connection is made, it is saved for reuse. */
-static DBusConnection * dbus_connect(void)
+static DBusConnection * dbus_connect_system(void)
 {
-    if ((dbus_context.connection == NULL) && ( ! dbus_context.connection_tried))
-    {
         DBusError error;
         dbus_error_init(&error);
         dbus_context.connection = dbus_bus_get(DBUS_BUS_SYSTEM, &error);
@@ -67,16 +74,57 @@
             dbus_error_free(&error);
         }
         dbus_context.connection_tried = TRUE;
-    }
 
     return dbus_context.connection;
 }
 
+static DBusConnection * dbus_connect_session(void)
+{
+        DBusError error;
+        dbus_error_init(&error);
+        dbus_context.connection = dbus_bus_get(DBUS_BUS_SESSION, &error);
+        if (dbus_context.connection == NULL)
+        {
+            g_warning(G_STRLOC ": Failed to connect to the session message bus: %s", error.message);
+            dbus_error_free(&error);
+        }
+        dbus_context.connection_tried = TRUE;
+
+    return dbus_context.connection;
+}
+
+
 /* Send a message. */
-static DBusMessage * dbus_send_message(DBusMessage * message, char * * error_text)
+static DBusMessage * dbus_send_message_system(DBusMessage * message, char * * error_text)
 {
     /* Get a connection handle. */
-    DBusConnection * connection = dbus_connect();
+    DBusConnection * connection = dbus_connect_system();
+    if (connection == NULL)
+        return FALSE;
+
+    /* Send the message. */
+    DBusError error;
+    dbus_error_init(&error);
+    DBusMessage * reply = dbus_connection_send_with_reply_and_block(connection, message, DBUS_TIMEOUT, &error);
+    dbus_message_unref(message);
+    if (reply == NULL)
+    {
+        if ((error.name == NULL) || (strcmp(error.name, DBUS_ERROR_NO_REPLY) != 0))
+        {
+            if (error_text != NULL)
+                *error_text = g_strdup(error.message);
+            g_warning(G_STRLOC ": DBUS: %s", error.message);
+        }
+        dbus_error_free(&error);
+    }
+    return reply;
+}
+
+/* Send a message. */
+static DBusMessage * dbus_send_message_session(DBusMessage * message, char * * error_text)
+{
+    /* Get a connection handle. */
+    DBusConnection * connection = dbus_connect_session();
     if (connection == NULL)
         return FALSE;
 
@@ -132,6 +180,36 @@
     }
     return result;
 }
+
+/* Read a result for a method that returns a string encoded boolean. */
+static gboolean dbus_read_result_sboolean(DBusMessage * reply)
+{
+    gboolean result = FALSE;
+    char* string_result;
+    if (reply != NULL)
+    {
+        /* Get the string result. */
+        DBusError error;
+        dbus_error_init(&error);
+        dbus_bool_t status = dbus_message_get_args(
+            reply,
+            &error,
+            DBUS_TYPE_STRING, &string_result,
+            DBUS_TYPE_INVALID);
+        if ( ! status)
+        {
+            g_warning(G_STRLOC ": DBUS: %s", error.message);
+            dbus_error_free(&error);
+        }
+        else
+        {
+            if (!strcmp(string_result, "yes"))
+                result = TRUE;
+        }
+        dbus_message_unref(reply);
+    }
+    return result;
+}
 #endif
 
 /*** ConsoleKit mechanism ***/
@@ -152,7 +230,7 @@
 static gboolean dbus_ConsoleKit_query(const char * const query)
 {
 #ifdef HAVE_DBUS
-    return dbus_read_result_boolean(dbus_send_message(dbus_ConsoleKit_formulate_message(query), NULL));
+    return dbus_read_result_boolean(dbus_send_message_system(dbus_ConsoleKit_formulate_message(query), NULL));
 #else
     return FALSE;
 #endif
@@ -163,7 +241,7 @@
 {
 #ifdef HAVE_DBUS
     char * error = NULL;
-    dbus_read_result_void(dbus_send_message(dbus_ConsoleKit_formulate_message(command), &error));
+    dbus_read_result_void(dbus_send_message_system(dbus_ConsoleKit_formulate_message(command), &error));
     return error;
 #else
     return NULL;
@@ -225,7 +303,7 @@
         DBUS_TYPE_INVALID);
 
     /* Send the message. */
-    DBusMessage * reply = dbus_send_message(message, NULL);
+    DBusMessage * reply = dbus_send_message_system(message, NULL);
     if (reply == NULL)
 	return FALSE;
 
@@ -252,7 +330,7 @@
 {
 #ifdef HAVE_DBUS
     char * error = NULL;
-    dbus_read_result_void(dbus_send_message(dbus_UPower_formulate_command(command), &error));
+    dbus_read_result_void(dbus_send_message_system(dbus_UPower_formulate_command(command), &error));
     return error;
 #else
     return NULL;
@@ -329,7 +407,7 @@
     DBusMessage * message = dbus_HAL_formulate_string_property_query(property);
     if (message == NULL)
         return FALSE;
-    DBusMessage * reply = dbus_send_message(message, NULL);
+    DBusMessage * reply = dbus_send_message_system(message, NULL);
     if (reply == NULL)
 	return FALSE;
     dbus_message_unref(reply);
@@ -343,7 +421,7 @@
 static gboolean dbus_HAL_boolean_query(const char * const property)
 {
 #ifdef HAVE_DBUS
-    return dbus_read_result_boolean(dbus_send_message(dbus_HAL_formulate_boolean_property_query(property), NULL));
+    return dbus_read_result_boolean(dbus_send_message_system(dbus_HAL_formulate_boolean_property_query(property), NULL));
 #else
     return FALSE;
 #endif
@@ -367,7 +445,7 @@
 
     /* Send the message and wait for a reply. */
     char * error = NULL;
-    dbus_read_result_void(dbus_send_message(message, &error));
+    dbus_read_result_void(dbus_send_message_system(message, &error));
     return error;
 #else
     return NULL;
@@ -421,3 +499,185 @@
 {
     return dbus_HAL_command("Hibernate");
 }
+
+/*** logind mechanism ***/
+
+#ifdef HAVE_DBUS
+/* Formulate a message to the logind Manager interface to query a property. */
+static DBusMessage * dbus_logind_formulate_query(const char * const query)
+{
+    return dbus_message_new_method_call(
+	"org.freedesktop.login1",
+        "/org/freedesktop/login1",
+        "org.freedesktop.login1.Manager",
+        query);
+}
+
+/* Formulate a message to the logind Manager interface. */
+static DBusMessage * dbus_logind_formulate_message(const char * const method)
+{
+    static dbus_bool_t interactive = FALSE;
+    DBusMessage * message = dbus_message_new_method_call(
+	"org.freedesktop.login1",
+        "/org/freedesktop/login1",
+        "org.freedesktop.login1.Manager",
+        method);
+    if (message != NULL)
+        dbus_message_append_args(message, DBUS_TYPE_BOOLEAN, &interactive, DBUS_TYPE_INVALID);
+    return message;
+}
+#endif
+
+/* Send a specified query to the logind interface and process a boolean result. */
+static gboolean dbus_logind_query(const char * const query)
+{
+#ifdef HAVE_DBUS
+    return dbus_read_result_sboolean(dbus_send_message_system(dbus_logind_formulate_query(query), NULL));
+#else
+    return FALSE;
+#endif
+}
+
+/* Send a specified command to the logind interface and process a void result. */
+static char * dbus_logind_command(const char * const command)
+{
+#ifdef HAVE_DBUS
+    char * error = NULL;
+    dbus_read_result_void(dbus_send_message_system(dbus_logind_formulate_message(command), &error));
+    return error;
+#else
+    return NULL;
+#endif
+}
+
+/* Read the can-poweroff property of logind. */
+gboolean dbus_logind_CanPowerOff(void)
+{
+    return dbus_logind_query("CanPowerOff");
+}
+
+/* Read the can-reboot property of logind. */
+gboolean dbus_logind_CanReboot(void)
+{
+    return dbus_logind_query("CanReboot");
+}
+
+/* Read the can-suspend property of logind. */
+gboolean dbus_logind_CanSuspend(void)
+{
+    return dbus_logind_query("CanSuspend");
+}
+
+/* Read the can-hibernate property of logind. */
+gboolean dbus_logind_CanHibernate(void)
+{
+    return dbus_logind_query("CanHibernate");
+}
+
+/* Invoke the PowerOff method on logind. */
+char * dbus_logind_PowerOff(void)
+{
+    return dbus_logind_command("PowerOff");
+}
+
+/* Invoke the Reboot method on logind. */
+char * dbus_logind_Reboot(void)
+{
+    return dbus_logind_command("Reboot");
+}
+
+/* Invoke the Suspend method on logind. */
+char * dbus_logind_Suspend(void)
+{
+    return dbus_logind_command("Suspend");
+}
+
+/* Invoke the Hibernate method on logind. */
+char * dbus_logind_Hibernate(void)
+{
+    return dbus_logind_command("Hibernate");
+}
+
+/*** LXDE mechanism ***/
+
+#ifdef HAVE_DBUS
+/* Formulate a message to the LXDE Session Manager interface. */
+static DBusMessage * dbus_LXDE_formulate_message(const char * const query)
+{
+    return dbus_message_new_method_call(
+        "org.lxde.SessionManager",
+        "/org/lxde/SessionManager",
+        "org.lxde.SessionManager",
+        query);
+}
+#endif
+
+/* Send a specified message to the LXDE interface and process a boolean result. */
+static gboolean dbus_LXDE_query(const char * const query)
+{
+#ifdef HAVE_DBUS
+    return dbus_read_result_boolean(dbus_send_message_session(dbus_LXDE_formulate_message(query), NULL));
+#else
+    return FALSE;
+#endif
+}
+
+/* Send a specified message to the LXDE interface and process a void result. */
+static char * dbus_LXDE_command(const char * const command)
+{
+#ifdef HAVE_DBUS
+    char * error = NULL;
+    dbus_read_result_void(dbus_send_message_session(dbus_LXDE_formulate_message(command), &error));
+    return error;
+#else
+    return NULL;
+#endif
+}
+
+/* Invoke the Logout method on LXDE. */
+char * dbus_LXDE_Logout(void)
+{
+    return dbus_LXDE_command("Logout");
+}
+
+/*** Lightdm mechanism ***/
+
+#ifdef HAVE_DBUS
+/* Formulate a message to the Lightdm interface. */
+static DBusMessage * dbus_Lightdm_formulate_message(const char * const query)
+{
+    return dbus_message_new_method_call(
+                "org.freedesktop.DisplayManager",
+                g_getenv ("XDG_SEAT_PATH"),
+                "org.freedesktop.DisplayManager.Seat",
+                query);
+}
+#endif
+
+/* Send a specified message to the Lightdm interface and process a boolean result. */
+static gboolean dbus_Lightdm_query(const char * const query)
+{
+#ifdef HAVE_DBUS
+    return dbus_read_result_boolean(dbus_send_message_session(dbus_Lightdm_formulate_message(query), NULL));
+#else
+    return FALSE;
+#endif
+}
+
+/* Send a specified message to the Lightdm interface and process a void result. */
+static char * dbus_Lightdm_command(const char * const command)
+{
+#ifdef HAVE_DBUS
+    char * error = NULL;
+    dbus_read_result_void(dbus_send_message_session(dbus_Lightdm_formulate_message(command), &error));
+    return error;
+#else
+    return NULL;
+#endif
+}
+
+/* Invoke the Logout method on LXDE. */
+char * dbus_Lightdm_SwitchToGreeter(void)
+{
+    return dbus_Lightdm_command("SwitchToGreeter");
+}
diff -uNr lxsession-0.4.6.1.orig/lxsession-logout/dbus-interface.h lxsession-0.4.6.1/lxsession-logout/dbus-interface.h
--- lxsession-0.4.6.1.orig/lxsession-logout/dbus-interface.h	2011-07-27 21:26:36.000000000 +0200
+++ lxsession-0.4.6.1/lxsession-logout/dbus-interface.h	2012-12-22 14:28:46.367031227 +0100
@@ -44,4 +44,18 @@
 extern char * dbus_HAL_Suspend(void);
 extern char * dbus_HAL_Hibernate(void);
 
+/* Interface to logind for shutdown, reboot, suspend, and hibernate. */
+extern gboolean dbus_logind_CanPowerOff(void);
+extern gboolean dbus_logind_CanRestart(void);
+extern char * dbus_logind_PowerOff(void);
+extern char * dbus_logind_Restart(void);
+extern gboolean dbus_logind_CanSuspend(void);
+extern gboolean dbus_logind_CanHibernate(void);
+extern char * dbus_logind_Suspend(void);
+extern char * dbus_logind_Hibernate(void);
+
+extern char * dbus_LXDE_Logout(void);
+
+extern char * dbus_Lightdm_SwitchToGreeter();
+
 #endif
diff -uNr lxsession-0.4.6.1.orig/lxsession-logout/lxsession-logout.c lxsession-0.4.6.1/lxsession-logout/lxsession-logout.c
--- lxsession-0.4.6.1.orig/lxsession-logout/lxsession-logout.c	2011-07-27 21:26:36.000000000 +0200
+++ lxsession-0.4.6.1/lxsession-logout/lxsession-logout.c	2012-12-22 14:29:04.994031240 +0100
@@ -69,12 +69,21 @@
     int reboot_HAL : 1;			/* Reboot is available via HAL */
     int suspend_HAL : 1;		/* Suspend is available via HAL */
     int hibernate_HAL : 1;		/* Hibernate is available via HAL */
+    int shutdown_logind : 1;		/* Shutdown is available via logind */
+    int reboot_logind : 1;		/* Reboot is available via logind */
+    int suspend_logind : 1;		/* Suspend is available via logind */
+    int hibernate_logind : 1;		/* Hibernate is available via logind */
     int switch_user_GDM : 1;		/* Switch User is available via GDM */
-    int switch_user_KDM : 1;		/* Switch User is available via KDM */
+    int switch_user_LIGHTDM : 1;	/* Switch User is available via GDM */
+    int switch_user_KDM : 1;		/* Switch User is available via LIGHTDM */
     int ltsp : 1;			/* Shutdown and reboot is accomplished via LTSP */
+
+    int lock_screen : 1;                /* Lock screen available */
+
 } HandlerContext;
 
 static gboolean lock_screen(void);
+static const gchar* determine_lock_screen(void);
 static gboolean verify_running(const char * display_manager, const char * executable);
 static void logout_clicked(GtkButton * button, HandlerContext * handler_context);
 static void change_root_property(GtkWidget* w, const char* prop_name, const char* value);
@@ -93,13 +102,32 @@
  */
 static gboolean lock_screen(void)
 {
-    if (!g_spawn_command_line_async("lxlock", NULL))
+    const gchar* program = determine_lock_screen();
+
+    if (program)
     {
+        g_spawn_command_line_async(program, NULL);
         return TRUE;
     }
     return FALSE;
 }
 
+static const gchar* determine_lock_screen(void)
+{
+    const gchar* program = NULL;
+
+    if (g_find_program_in_path("xdg-screensaver"))
+    {
+        program = "xdg-screensaver lock";
+    }
+    else if (g_find_program_in_path("lxlock"))
+    {
+        program = "lxlock";
+    }
+    return program;
+}
+
+
 /* Verify that a program is running and that an executable is available. */
 static gboolean verify_running(const char * display_manager, const char * executable)
 {
@@ -187,6 +215,8 @@
         error_result = dbus_ConsoleKit_Stop();
     else if (handler_context->shutdown_HAL)
         error_result = dbus_HAL_Shutdown();
+    else if (handler_context->shutdown_logind)
+        error_result = dbus_logind_PowerOff();
 
     if (error_result != NULL)
         gtk_label_set_text(GTK_LABEL(handler_context->error_label), error_result);
@@ -208,6 +238,8 @@
         error_result = dbus_ConsoleKit_Restart();
     else if (handler_context->reboot_HAL)
         error_result = dbus_HAL_Reboot();
+    else if (handler_context->reboot_logind)
+        error_result = dbus_logind_Reboot();
 
     if (error_result != NULL)
         gtk_label_set_text(GTK_LABEL(handler_context->error_label), error_result);
@@ -225,6 +257,8 @@
         error_result = dbus_UPower_Suspend();
     else if (handler_context->suspend_HAL)
         error_result = dbus_HAL_Suspend();
+    else if (handler_context->suspend_logind)
+        error_result = dbus_logind_Suspend();
 
     if (error_result != NULL)
         gtk_label_set_text(GTK_LABEL(handler_context->error_label), error_result);
@@ -242,6 +276,8 @@
         error_result = dbus_UPower_Hibernate();
     else if (handler_context->hibernate_HAL)
         error_result = dbus_HAL_Hibernate();
+    else if (handler_context->hibernate_logind)
+        error_result = dbus_logind_Hibernate();
 
     if (error_result != NULL)
         gtk_label_set_text(GTK_LABEL(handler_context->error_label), error_result);
@@ -258,6 +294,17 @@
         g_spawn_command_line_sync("gdmflexiserver --startnew", NULL, NULL, NULL, NULL);
     else if (handler_context->switch_user_KDM)
         g_spawn_command_line_sync("kdmctl reserve", NULL, NULL, NULL, NULL);
+    else if (handler_context->switch_user_LIGHTDM)
+        dbus_Lightdm_SwitchToGreeter();
+    gtk_main_quit();
+}
+
+/* Handler for "clicked" signal on Lock button. */
+static void lock_screen_clicked(GtkButton * button, HandlerContext * handler_context)
+{
+    gtk_label_set_text(GTK_LABEL(handler_context->error_label), NULL);
+
+    lock_screen();
     gtk_main_quit();
 }
 
@@ -435,6 +482,28 @@
         handler_context.hibernate_HAL = TRUE;
     }
 
+    /* Initialize capabilities of the logind mechanism. */
+    if (!handler_context.shutdown_available && dbus_logind_CanPowerOff())
+    {
+        handler_context.shutdown_available = TRUE;
+        handler_context.shutdown_logind = TRUE;
+    }
+    if (!handler_context.reboot_available && dbus_logind_CanReboot())
+    {
+        handler_context.reboot_available = TRUE;
+        handler_context.reboot_logind = TRUE;
+    }
+    if (!handler_context.suspend_available && dbus_logind_CanSuspend())
+    {
+        handler_context.suspend_available = TRUE;
+        handler_context.suspend_logind = TRUE;
+    }
+    if (!handler_context.hibernate_available && dbus_logind_CanHibernate())
+    {
+        handler_context.hibernate_available = TRUE;
+        handler_context.hibernate_logind = TRUE;
+    }
+
     /* If we are under GDM, its "Switch User" is available. */
     if (verify_running("gdm", "gdmflexiserver"))
     {
@@ -442,6 +511,34 @@
         handler_context.switch_user_GDM = TRUE;
     }
 
+    /* If we are under GDM3, its "Switch User" is available. */
+    if (verify_running("gdm3", "gdmflexiserver"))
+    {
+        handler_context.switch_user_available = TRUE;
+        handler_context.switch_user_GDM = TRUE;
+    }
+
+    /* lightdm also use gdmflexiserver */
+    if (verify_running("lightdm", "gdmflexiserver"))
+    {
+        handler_context.switch_user_available = TRUE;
+        handler_context.switch_user_GDM = TRUE;
+    }
+
+    /* lightdm also use gdmflexiserver */
+    if (verify_running("lightdm", "gdmflexiserver"))
+    {
+        handler_context.switch_user_available = TRUE;
+        handler_context.switch_user_GDM = TRUE;
+    }
+
+    /* lightdm can also be find by the env */
+    if (g_getenv("XDG_SEAT_PATH"))
+    {
+        handler_context.switch_user_available = TRUE;
+        handler_context.switch_user_LIGHTDM = TRUE;
+    }
+
     /* If we are under KDM, its "Switch User" is available. */
     if (verify_running("kdm", "kdmctl"))
     {
@@ -451,7 +548,18 @@
 
     /* LTSP support */
     if (g_getenv("LTSP_CLIENT"))
+    {
         handler_context.ltsp = TRUE;
+        handler_context.shutdown_available = TRUE;
+        handler_context.reboot_available = TRUE;
+    }
+
+    /* Lock screen */
+    const gchar* very_lock_screen = determine_lock_screen();
+    if (very_lock_screen)
+    {
+        handler_context.lock_screen = TRUE;
+    }
 
     /* Make the button images accessible. */
     gtk_icon_theme_append_search_path(gtk_icon_theme_get_default(), PACKAGE_DATA_DIR "/lxsession/images");
@@ -596,6 +704,17 @@
         gtk_box_pack_start(GTK_BOX(controls), switch_user_button, FALSE, FALSE, 4);
     }
 
+    /* Create the Lock Screen button. */
+    if (handler_context.lock_screen && !handler_context.ltsp)
+    {
+        GtkWidget * lock_screen_button = gtk_button_new_with_mnemonic(_("L_ock Screen"));
+        GtkWidget * image = gtk_image_new_from_icon_name("system-lock-screen", GTK_ICON_SIZE_BUTTON);
+        gtk_button_set_image(GTK_BUTTON(lock_screen_button), image);
+        gtk_button_set_alignment(GTK_BUTTON(lock_screen_button), 0.0, 0.5);
+        g_signal_connect(G_OBJECT(lock_screen_button), "clicked", G_CALLBACK(lock_screen_clicked), &handler_context);
+        gtk_box_pack_start(GTK_BOX(controls), lock_screen_button, FALSE, FALSE, 4);
+    }
+
     /* Create the Logout button. */
     GtkWidget * logout_button = gtk_button_new_with_mnemonic(_("_Logout"));
     GtkWidget * image = gtk_image_new_from_icon_name("system-log-out", GTK_ICON_SIZE_BUTTON);