diff --git a/lib/src/catalan/LexiconCat.gf b/lib/src/catalan/LexiconCat.gf
index 22f20d81c..2d7be1aaa 100644
--- a/lib/src/catalan/LexiconCat.gf
+++ b/lib/src/catalan/LexiconCat.gf
@@ -9,7 +9,7 @@ flags
 oper
     regFN : Str -> N = \s -> femN (regN s) ;
     regMN : Str -> N = \s -> regN s ; 
-	irregMN : Str -> Str -> N = \pa,pans ->  M.mkNounIrreg pa pans masculine ;
+	irregMN : Str -> Str -> N = \pa,pans -> M.mkNounIrreg pa pans masculine ** {lock_N=<>} ;
 	saberV : V = verbV (saber_99 "saber") ;
 
 lin