diff --git a/lib/Hikaru/Form.hs b/lib/Hikaru/Form.hs
index e4d95e37721a691ffaf4a599ea2604b56fe79e07..8eb2b3da2fc1c3e0ae64c663d8b569760fd73f9e 100644
--- a/lib/Hikaru/Form.hs
+++ b/lib/Hikaru/Form.hs
@@ -381,6 +381,10 @@ where
     deriving (Show)
 
   instance Localizable FormMessage where
+    -- Czech strings
+    localize "cs" FormMsgFieldRequired = Just "Toto pole je povinné."
+    localize "cs" FormMsgTokenInvalid  = Just "Platnost formuláře vypršela. Zkuste to znovu."
+
     -- English strings
     localize "en" FormMsgFieldRequired = Just "This field is required."
     localize "en" FormMsgTokenInvalid  = Just "The form has expired. Try again."