UJS & partial possible bug

Hi,

I'm new to rails, so this might be my fault instead of a bug. But at least it sounds odd. Here are a few files:

list.html.erb

<table>
<% @boxes.each do |box| %>
  <tr>
    <td><%= box.name %></td>
  </tr>
<% end %>
</table>
<div id="add">
  <%=
    render :partial => "list_add"
  %>
</div>

_list_add.html.erb

<%=
  link_to_function("add a new box") do |page|
    page.replace_html "add", :partial => "list_new"
  end
%>

_list_new.html.erb

<%=
  link_to_function("finished adding a new box") do |page|
    page.replace_html "add", ":partial => list_add"
  end
%>

This code crashes the WEBrick server when trying to render list.html.erb:

macbook-pro-de-philippe-lang:attikdb plang$ rails s
=> Booting WEBrick
=> Rails 3.0.0 application starting in development on http://0.0.0.0:3000
=> Call with -d to detach
=> Ctrl-C to shutdown server
[2010-09-22 11:09:56] INFO  WEBrick 1.3.1
[2010-09-22 11:09:56] INFO  ruby 1.9.2 (2010-08-18) [x86_64-darwin10.4.0]
[2010-09-22 11:09:56] INFO  WEBrick::HTTPServer#start: pid=2959 port=3000
Illegal instruction
macbook-pro-de-philippe-lang:attikdb plang$

Browser says:

Erreur 324 (net::ERR_EMPTY_RESPONSE) : Erreur inconnue

A small change and the server does not crash anymore:

_list_new.html.erb

<%=
  link_to_function("finished adding a new box") do |page|
    page.replace_html "add", "rendering list_add partial here..."
  end
%>

It looks like rails does not like partials rendering each other through UJS.

What I'm trying to acomplish here is some kind of web 2.0 in-place editing at the bottom of a list. There might be a better way of doing that, sure!

My config: ruby 1.9.2, rails 3.0.0