How to have the scaffold to generate another partial view template file

Question

I'm trying to customize my scaffold generator, and I would like to have a new partial for the view in the same directory, in particular _item to be called both inside index and show. I can get all the templates but I'm not able to generate this file through

rails g scaffold foo name:string

I tried to put _item.erb in /lib/templates/erb/scaffold/ (together with the other files) but it is ignored- Does anybody have a clue?

I use ruby on rails 3, but please let me know if the solution is valid for rails 2 as well. I also use simple_form (thus I already have the _form partial), but I think the solution should be valid even without it.