is it possible to call a rjs file from a javascript function??
Not sure if this is what you're asking, but you can do the following:
new Ajax.Request('some_url', ...)
(Check out prototypejs.org for details). That will issue a request to the url as an ajax request... which will ask for an 'rjs' response. Better still, if you don't need to embed the call in other javascript then you can do this:
remote_function(:url=>'some_url', :submit=>'form_id', etc.)
http://www.railsbrain.com/api/rails-2.0.2/doc/index.html?a=M001834&name=remote_function