clear not working on edge Rails with has_many :through?

[rubyonrails-talk]

I have three models in an app using edge rails (currently r4833):
class Magazine < ActiveRecord::Base
has_many :subscriptions
has_many :users, :through => :subscriptions
end
class Subscription < ActiveRecord::Base
belongs_to :user
belongs_to :magazine
end
class User < ActiveRecord::Base
has_many :subscriptions

More... (http://groups.google.com/group/rubyonrails-talk/msg/d333d7884d399a89)