Nhibernate HQL where IN query

Im trying to return a SimpleQuery list that queries a single table and uses IN. I can get this to work using

return new List<Jobs>(
    ActiveRecordMediator<Jobs>.FindAll(Expression.In("ServiceId", ids))
);

However this is really really really slow. So id like to do something like this

SimpleQuery<Job> query = 
    new SimpleQuery<Job>(@"from Job as j where ? in (j.ServiceId)", ids);

return new List<Job>(query.Execute());

However I cant get the SimpleQuery to work. I cant find any documentation covering this and was hoping someone out there would be able to help.

Thanks