Form fields with ajax listener

Folks,

I have an app that collects customer info and asks the user to click a
checkbox if he has a billing address that’s different from his shipping
info. There’s an event listener that detects the checkbox click and
renders a partial with the billing address info. Works great. Except
that the billing address stuff is not being dumped into params and is
therefore not being saved in the model.

I have another app with this same functionality that works perfectly…
no idea what’s gone wrong here. suggestions?

main view

<%= form_tag(:action => ‘save_customer’) %>
<%= javascript_include_tag ‘prototype’ %>

Please enter your details below

Name
<%= text_field("customer", "name", "size" => 40 ) %>
Your e-mail address
<%= text_field("customer", "email", "size" => 40 ) %>

Your shipping address

<%= text_field(“customer”, “ship_address1”, “size” => 40 ) %>

Address line 2
<%= text_field("customer", "ship_address2", "size" => 40 ) %>
City
<%= text_field("customer", "ship_city", "size" => 40 ) %>
State
<%= options = [["Select a state", ""]] + Customer::STATE_NAMES select("customer", "ship_state", options) %>
Zipcode
<%= text_field("customer", "ship_zip", "size" => 10 ) %>
Country
<%= options = [["Select a country", ""]] + Customer::COUNTRY_NAMES select("customer", "ship_country", options) %>
Check if you have a different billing address

<%= check_box_tag(“different_bill”) %>

<%= observe_field(:different_bill, :update => “billinfo”, :url => {
:controller=>‘shirts’, :action => ‘billing_address’ }, :with =>
“‘id=’+value” ) %>

Payment method
Credit CardPaypal

<%= submit_tag "Save" %>
<%= end_form_tag %>

partial

Your billing address

<%= text_field(“customer”, “bill_address1”, “size” => 40 ) %>

Address line 2
<%= text_field("customer", "bill_address2", "size" => 40 ) %>
City
<%= text_field("customer", "bill_city", "size" => 40 ) %>
State
<%= options = [["Select a state", ""]] + Customer::STATE_NAMES select("customer", "bill_state", options) %>
Zipcode
<%= text_field("customer", "bill_zip", "size" => 10 ) %>
Country
<%= options = [["Select a country", ""]] + Customer::COUNTRY_NAMES select("customer", "bill_country", options) %>

controller action

def billing_address
  if  params[:id] == "1"
  render :partial => 'billinfo', :layout => false
 else
    render :nothing=>true
 end
end