An error of Missing template

I use observe_form to monitor a form, whenever a field changed in this
form, an (Missing template builder/update_make_view_info.js.erb…)
error will be thrown. I don’t want to use js format. I want to use
html.erb format. How can I avoid it and why it looks for
update_make_view_info.js.erb? This is my action code:

def update_make_view_info

render :patial=>‘project_version’

I would be interested in running a template engine to create output in
any xml-format from Ruby/JRuby.
I think using the <%…%> notation of rails would do, but I don’t want
this to go to the web, but rather keep
it in the file system as output.

Best regards