Simple relations are failing

Can anyone see why the league_organizers relation is failing.

class League < ActiveRecord::Base
  has_many :league_admins
  has_many :league_organizers, :through => :league_admins, :class_name
=> "User"

class LeagueAdmin < ActiveRecord::Base
  belongs_to :league
  belongs_to :user

I am getting the following error message:

ActiveRecord::HasManyThroughSourceAssociationNotFoundError: Could not
find the source association(s) :league_admins in model LeagueAdmin. Try
'has_many :league_organizers, :through => :league_admins, :source =>
<name>'. Is it one of :league or :user?
  from (irb):2

I tried adding the source option with and without the class_name but it
still fails. As I mentioned it is a simple relation. Has something
changed in the last while to cause this?

I am currently using Rails 2.2.2

Thanks for the help.