How to set an empty value in a lift select element?

Question

Hi people, I am trying to set an empty value (as a first choice) in a lift select element:

SHtml.select(("", "") :: (MyObject.findAll(By(MyObject.creator, User.currentUser.open_!.id))), ...

However it gives me this error:

error: type mismatch;
found: List[(String, java.lang.Object)]
required: Seq[(String, String)]

Any ideas? Thanks!