Issues with acts_as_taggable plugin

Not the gem.

I've got something working in console, but not in controller. Any idea
why?

This is the plugin not the gem of acts_as_taggable

*View*
<code>
<h1>Listing elements</h1>

<% if @elements.blank? %>
  <p>There are currently no elements in the system tagged <%=
"&quot;#{params[:tag_name]}&quot;" %>.</p>
<% else %>
  <p>Currently tracking <%= @elements.size %> elements in the system
tagged <%= "&quot;#{params[:tag_name]}&quot;" %>.</p>

<table>
  <tr>
  </tr>

    <%= render :partial => 'element', :collection => @elements %>

</table>

<% end %>
<br />

<%= link_to 'New element', new_element_path %>
</code>

This returns that the array is empty and there's nothing in the tag in
http://localhost:3000/elements/tagged/:tag_name

SO teh view is seeing it, but the controller is not getting it. Because
in the console, using a string in place of params(:tag_name) returns an
actual entry.

*Controller*

<code>
  def tagged
    # This should take the :tag_name in the url string and pull
elements that match
    # It does not. I suck as a programmer.
    @elements = Element.find_tagged_with(params[:tag_name])

    respond_to do |format|
      format.html # index.rhtml
      format.xml { render :xml => @elements.to_xml }
    end
  end
</code>

*Models*

<code>
class Element < ActiveRecord::Base

  acts_as_taggable
  [...]
end
</code>

*CONSOLE*

This does work:
<code>
soho:~/Sites/work/koji jathayde$ script/console
Loading development environment.

@elements = Element.find_tagged_with("spam")

DEPRECATION WARNING: The :dependent => true option is deprecated and
will be removed from Rails 2.0. Please use :dependent => :destroy
instead. See http://www.rubyonrails.org/deprecation for details. See
http://www.rubyonrails.org/deprecation for details. (called from
has_many at
/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.14.4.5618/lib/active_record/associations.rb:550)
=> [#<Element:0x330a8d8 @attributes={"name"=>"Koji Test One",
"updated_at"=>"2006-11-30 18:16:40", "id"=>"1", "description"=>"supa
sexy description", "filename"=>nil, "element_type_id"=>"3",
"created_at"=>nil}]

But this does not (because there is no value in params[:tag_list]:

@elements = Element.find_tagged_with(params[:tag_list])

NameError: undefined local variable or method `params' for
#<Object:0x1f59f0>
        from (irb):4
</code>