Functional Test w/ Two Models in One Controller.

Hi,

I'm trying to write a functional test, but I'm having problems pulling
two sets of models from my post request. I know how to grab one model
using "post :<action_name>, :<model> => { <params> }", but how do I do
it if i have another model within that post?

For example, I have a user_profile model and a user_settings model.
The view has them as profile and settings. I've tried both
"post :update, :profile => { junk_here}, :settings => { more_junk }"
as one whole post and as "post :update, :profile => { junk_here};
post :update, :settings => { more_junk }" as two different requests.
When i try to assert_valid assigns on my 2nd model, the model returns
as nil. Is there something I am missing? Thanks!