Rails - Aug 2009 - use observe_field within form_tag

Hey,

I''m trying to observe a field that is inside a form_tag like so:

 <% form_tag ''send_mail'' do %>
 <%= select_tag ''select_club'',
options_from_collection_for_select(clubs,''id'',''name''),
:class =>
''ComboBox'' %>

 <%= observe_field ''select_club'',:url=>{:action =>
''clubs_changed''}  %>
 <% end %>

When I run this in FireFox gives me the following JavaScript error:
Form is not defined
and then points to the generated javascript:
new Form.Element.EventObserver(''select_club'',
function(element, value)
{new Ajax.Request(''/mailings/clubs_changed'',
{asynchronous:true,
evalScripts:true, parameters:value +
''&authenticity_token='' +
encodeURIComponent(''06f49bb619c38f8d0ea988932e4324abbd8511ef'')})})

My html does contain a form so I don''t exactly know where to look
anymore.

Thanks!
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refer
http://blogofchirag.blogspot.com/2008/09/observefield-example-ruby-on-rails.html
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Posted via http://www.ruby-forum.com/.

Wap Addon wrote:
> 
> 
> refer
>
http://blogofchirag.blogspot.com/2008/09/observefield-example-ruby-on-rails.html
This doesn''t really help me.
The link doesn''t even use a form_tag.
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