diff --git a/app/setup/FormFactory.scala b/app/setup/FormFactory.scala
index b0a6c6a3d9..593f72844d 100644
--- a/app/setup/FormFactory.scala
+++ b/app/setup/FormFactory.scala
@@ -60,7 +60,9 @@ final class FormFactory(
       "mode" -> mode(ctx.isAuth),
       "eloRange" -> eloRange,
       "color" -> nonEmptyText.verifying(Color.names contains _)
-    )(HookConfig.<<)(_.>>) verifying ("Invalid clock", _.validClock)
+    )(HookConfig.<<)(_.>>)
+      .verifying("Invalid clock", _.validClock)
+      .verifying("Can't create rated unlimited in lobby", _.noRatedUnlimited)
   )
 
   def hookConfig(implicit ctx: Context): IO[HookConfig] = ctx.me.fold(
diff --git a/app/setup/HookConfig.scala b/app/setup/HookConfig.scala
index 48291b99ca..918aa07c0d 100644
--- a/app/setup/HookConfig.scala
+++ b/app/setup/HookConfig.scala
@@ -32,6 +32,8 @@ case class HookConfig(
     i = increment,
     m = mode.id,
     e = eloRange.toString)
+
+  def noRatedUnlimited = mode.casual || clock
 }
 
 object HookConfig extends BaseHumanConfig {
diff --git a/todo b/todo
index 160b3d2372..fdf1ac722d 100644
--- a/todo
+++ b/todo
@@ -36,6 +36,5 @@ admin ip search interface
 analyse: show main line for every move http://en.lichess.org/forum/lichess-feedback/about-the-analysis-feature#5
 analyse: show cp every move 
 clock in AI game
-disable rated unlimited in lobby http://en.lichess.org/forum/lichess-feedback/unlimited-time-limit?page=2#13
 try to show last analysis cp on graph (move 26) http://en.lichess.org/analyse/bwxnx0al
 elo range must contain player elo