-PKG_CHECK_MODULES(LIBDOCUMENT, gtk+-2.0 >= $GTK_REQUIRED gio-2.0 >= $GLIB_REQUIRED)
-PKG_CHECK_MODULES(LIBVIEW, gtk+-2.0 >= $GTK_REQUIRED gthread-2.0 gio-2.0 >= $GLIB_REQUIRED)
-PKG_CHECK_MODULES(BACKEND, gtk+-2.0 >= $GTK_REQUIRED)
-PKG_CHECK_MODULES(FRONTEND_CORE, gtk+-2.0 >= $GTK_REQUIRED gthread-2.0 gio-2.0 >= $GLIB_REQUIRED)
-PKG_CHECK_MODULES(PREVIEWER, gtk+-2.0 >= $GTK_REQUIRED gthread-2.0 gio-2.0 >= $GLIB_REQUIRED)
+
+PKG_CHECK_MODULES(LIBDOCUMENT, gtk+-3.0 >= $GTK_REQUIRED gio-2.0 >= $GLIB_REQUIRED)
+PKG_CHECK_MODULES(LIBVIEW, gtk+-3.0 >= $GTK_REQUIRED gail-3.0 >= $GTK_REQUIRED gthread-2.0 gio-2.0 >= $GLIB_REQUIRED)
+PKG_CHECK_MODULES(BACKEND, gtk+-3.0 >= $GTK_REQUIRED)
+PKG_CHECK_MODULES(FRONTEND_CORE, gtk+-3.0 >= $GTK_REQUIRED gthread-2.0 gio-2.0 >= $GLIB_REQUIRED)