Rails - Jul 2005 - render :file problem

I have MyControllerBase (< ApplicationController) from which all my
controllers
inherit.  I''d like the search methods to all use the same template.

I''ve tried something like: 
    render :file => "#{template_root}test"

looking for a template at ../views/test.rhtml ... but I get an error:

No rhtml, rxml, or delegate template found for file/app/views/test.rhtml

I''ve also tried absolute paths, etc.  

And thinking ahead, do I need to pass something for local_assigns, or will this
already pick up instance variables from the current controller?