NHibernate Criteria against an <ANY> Mapping

I have a Project model that has a property of type IProjectWorker, this could either be a single User or a Team. In Castle ActiveRecord it's defined like this:

[Any(typeof(int), MetaTyp开发者_JAVA百科e = typeof(string), TypeColumn = "WorkerType", IdColumn = "WorkerID", Cascade = CascadeEnum.None)]
[Any.MetaValue("USER", typeof(User))]
[Any.MetaValue("TEAM", typeof(Team))]
public IProjectWorker Worker { get; set; }

Now I need to be able to search for projects where the worker's name contains some text. My initial reaction was something like this:

query
   .CreateAlias("Worker", "Worker")
   .Add(Restrictions.InsensitiveLike("Worker.WorkerName", SearchText, MatchMode.Anywhere));

But this gives me an error-- "any types do not have a unique referenced persister". This makes sense, it doesn't know how to handle joining to the two different tables for the search.

Can I make two different aliases for each table and do a Restrictions.Or() across them? I tried it, but couldn't quite get it right. Or is there some other way to do this using criteria that I'm missing? Or am I going to have to use HQL instead?