Index: gedit-plugin-manager.c
===================================================================
--- gedit-plugin-manager.c	(revision 6112)
+++ gedit-plugin-manager.c	(working copy)
@@ -323,7 +323,6 @@
 			   GtkTreeModel       *model,
 			   gboolean            active)
 {
-	GeditPluginsEngine *engine;
 	GeditPluginInfo *info;
 	gboolean res = TRUE;
 	
@@ -774,9 +773,44 @@
 		return;
 	}
 
-	gtk_list_store_set (model, &iter, ACTIVE_COLUMN, gedit_plugin_info_is_active (info), -1);
+	gtk_list_store_set (GTK_LIST_STORE (model), &iter, ACTIVE_COLUMN, gedit_plugin_info_is_active (info), -1);
 }
 
+gboolean
+query_tooltip_cb (GtkWidget  *widget,
+                  gint        x,
+                  gint        y,
+                  gboolean    keyboard_mode,
+                  GtkTooltip *tooltip,
+                  gpointer useless)
+{
+	GtkTreeModel *model;
+	GtkTreePath *path;
+	GtkTreeIter iter;
+	gboolean is_row;
+	GeditPluginInfo *info;
+	
+	is_row = gtk_tree_view_get_tooltip_context (GTK_TREE_VIEW (widget),
+						    &x, &y,
+						    keyboard_mode,
+						    &model,
+						    &path,
+						    &iter);
+
+	if (is_row)
+	{
+		gtk_tree_model_get (model, &iter, INFO_COLUMN, &info, -1);
+		if (!gedit_plugin_info_is_available (info))
+		{
+			gtk_tooltip_set_text (tooltip,
+					      _("This plugin is not available.\nPlease check your instalation"));
+			return TRUE;
+		}
+	}
+	
+	return FALSE;
+}
+
 static void 
 gedit_plugin_manager_init (GeditPluginManager *pm)
 {
@@ -817,6 +851,13 @@
 
 	pm->priv->tree = gtk_tree_view_new ();
 	gtk_container_add (GTK_CONTAINER (viewport), pm->priv->tree);
+	/*We have to set the has-tooltip property to TRUE to add Tooltips to rows*/
+	g_object_set (pm->priv->tree,
+		      "has-tooltip", TRUE,
+		      NULL);
+	g_signal_connect (pm->priv->tree,
+			  "query-tooltip",
+			  G_CALLBACK (query_tooltip_cb), NULL);
 
 	hbuttonbox = gtk_hbutton_box_new ();
 	gtk_box_pack_start (GTK_BOX (pm), hbuttonbox, FALSE, FALSE, 0);
