select helper still the worth thing in rails...

I have been trying all the day to make it happen, initial display is
fine , but I cannot redisplay the selected value once the choice is
done in my select helper

I setup my slector in a helper  (need to include the first option
'all', as a prompt is displayed only once....
in my partial
def company_role_selection(selection=nil)
     roles= [['all', 0]]
    roles +=  company_roles.collect {|h| [ h.name,
company_roles.index(h)]}.compact.uniq
    select('role', 'id', roles, {:selected => selection} ,{:onchange
=> "$('select_role').submit()"})
end

in my controller, I get the selection
@selection = params[:role][:id]

then I find and display the users...

and I redisplay the page with the form and the list

<% form_for(:user, :url => user_path(@user), :html => {:method
=> :get, :id => 'select_role' }) do |f| %>
	<%= render :partial => 'select_role' , :locals=>{:selection =>
@selection } -%>
<% end %>

<div id="hits" >