Arrays with fields_for ?

This is a simpler version of a question I asked earlier that was probably too long. I am trying to combine an array with fields_for, if this is possible.

I have classes Account and Employee, with a many-to-many relationship. I define a model class AccountEmployeeRelation to link the two. The link class also contains an extra field called "role".

I want to create an Account and assign employees in one form. (The employees already exist). I have figured out how to add one employee (not sure if this is the best way, but it works):

Controller:

      def new         @account = Account.new         @r = AccountEmployeeRelation.new       end

      def create         @account = Account.new(params[:account])         @r = AccountEmployeeRelation.new(params[:r])         @account.account_employee_relations << @r         @account.save         @r.save         redirect_to :action => :list       end

View, new.rhtml:

    <% form_for :account, :url => { :action => :create } do |form| %>     Title: <%= form.text_field :title %><br/>

    <% fields_for :r do |r|%>        Employee: <%= r.select (:employee_id, Employee.find(:all).map{|u|     [u.name, u.id]}) %><br/>        Role: <%= r.select (:role, ['Boss', 'King', 'Queen']) %>     <% end %>

    <%= submit_tag %>     <% end %>

But how do I assign multiple employees in one form? I would guess that 'new' needs to look like: (up to 3 employees)

      def new         @account = Account.new         @rs =         3.times do           @rs << AccountEmployeeRelation.new         end       end

But the following does not work for the view. I get this error:

`@#<AccountEmployeeRelation:0xb7628038>' is not allowed as an instance

variable name|

    <% for r in @rs %>     <% fields_for r do |f| %>        Employee: <%= f.select (:employee_id, Employee.find(:all).map{|u|     [u.name, u.id]}) %><br/>        Role: <%= f.select (:role, ['Boss', 'King', 'Queen']) %>     <% end %>

Any pointers are appreciated.

Sorry for the bump, but I'm still hoping someone can help.