unable to observe select_tag's value

Hi,

I am trying to observe a select_tag’s value, and insert a partial inside the page based on that value. Here’s the code:

#index.html.erb

<% form_tag do %>

<%= select_tag ‘product_id’, options_from_collection_for_select(@products, ‘id’, ‘pro_name’), {:id => ‘product_id’} %>

<%= select_tag ‘taxation_id’, options_from_collection_for_select(@taxations, ‘id’, ‘tax_name’), {:id => ‘taxation_id’} %>

<%= observe_field ‘product_id’, :url => {:controller => ‘regulations’, :action => ‘show’}, :with => “‘id=’ + value” %>

<% end %>

#regulations_controller.rb

def show

@regulation = Regulation.find_by_product_id params[:id]

respond_to do |format|

  format.html # show.html.erb

  format.xml  { render :xml => @regulation }

  format.js

end

end

#show.js.rjs

page.alert(“you are here!”)

page.insert_html :bottom, ‘regulations’, :partial => ‘all’, :locals => { :regs => @regulations }

Index.html looks like this:

joomla

VAT

Is something missing or wrong in the above code? even the alert is not getting called.

Regards