diff --git a/lib/awful/widget/textclock.lua.in b/lib/awful/widget/textclock.lua.in
index b3e0650e..ee0e43d8 100644
--- a/lib/awful/widget/textclock.lua.in
+++ b/lib/awful/widget/textclock.lua.in
@@ -32,7 +32,7 @@ function textclock.new(format, timeout)
     local w = textbox()
     local t = timer { timeout = timeout }
     t:connect_signal("timeout", function()
-        w:set_markup(os.date(format))
+        w:set_markup(require("lgi").GLib.DateTime.new_now_local():format(format))
         t.timeout = calc_timeout(timeout)
         t:again()
     end)