IE issues (go figure)

So, I have this issue with IE. The code below is from my view and makes an ajax call to return a list of subcategories. The form works just dandy in Chrome/Safari, and Firefox, but IE the Submit button does absolutely nothing. Click it--nothing--no error, no nothing.

Anybody have an ideas?

# My view

<h1>New Listing</h1>

<%= error_messages_for :listing %>

<% form_for(@listing) do |f| %>

  <%= render :partial => "form", :locals => {:f => f} %>

  <p>     <%= f.submit "Create", :disable_with => "Saving..." %>     <%= link_to 'Back', show_my_listings_url(current_user.id) %>   </p> <% end %>

# Form partial

<%= f.hidden_field :user_id, :value => current_user.id %>

<p>   <b>Name</b><br />   <%= f.text_field :name %> </p>

<div id="categories">   <p>     <b>Category:</b><br />     <% form_tag "", :id=>"categories" do %>       <% for category in @categories %>         <% if @listing.category %>         <% if @listing.category.parent == category %>           <%= radio_button "category", :category_id, category.id, :checked => true %> <%= category.name %><br />         <% else %>           <%= radio_button "category", :category_id, category.id %> <%= category.name %><br />         <% end %>       <% else %>           <%= radio_button "category", :category_id, category.id %> <%= category.name %><br />       <% end %>       <% end %>     <% end %>   </p> </div>

<p>   <b>Subcategory:</b><br />   <div id="listing-subcategories">     <%= render :partial => "categories/subcategories", :locals => {:subcategories => @subcategories} %>   </div> </p>

<%= observe_form :categories,          :frequency => 0.5,          :url => { :controller => "categories", :action => "ajax_subcategories" } %>

<p>   <b>Gender:</b><br />   <%= f.radio_button :gender, "Male" %> Male   <%= f.radio_button :gender, "Female" %> Female </p>

<p>     <b>Location:</b><br />     <%= f.text_field :location, :value => current_user.location %> </p>

<p>   <b>Price</b><br />   <%= f.text_field :price %> </p>

<p>   <b>Description</b><br />   <%= f.text_area :description %> </p>