Rails 3 and Mongoid: Can't seem to setup a one-to-many relationship

I have a User model and a Tracker model

the goal is to have a user having: - one tracker that was created by this user - one referer tracker to the user

On the other hand, each tracker: - belong to one user, the one one who created it - have many user referees (who ever used this开发者_C百科 tracker as a referer)

So I built my model the following way:

class User
.
.
  references_one :referer_tracker, :class_name => "Tracker", :inverse_of => :referees
  references_one :tracker, :class_name => "Tracker", :inverse_of => :owner
.
.
end

class Tracker
.
.
  belongs_to :owner, :class_name => "User", :inverse_of => :tracker
  has_many :referees, :class_name => "User", :inverse_of => :referer_tracker
.
.
end

The User.tracker / Tracker.owner relationship works just fine. But I can't get the User.referer_tracket // Tracker.referees one to work.

With the console if do something like this:

trackerX.referees << userX
trackerX.save
=> false because of invalid referees

on the other end if I try to do: userX.referer_tracker = trackerX I get an error: NoMethodError: undefined method `entries' for #

I am running out of ideas to try... I am running RoR 3.03 and Mongoid 2.0.0.rc.7

Thanks,

Alex