nested model form error messages

I have a form that updates 3 models. To the end user its just a form
and they don't need to know what is happening behind the scenes. My
problem is that the error_messages_for prefixes errors on associations
with their name. I have a user model that has many addresses. When
a user is signing up errors on address fields show up as

Addresses first name can't be blank

I would rather if it just said

=> First name can't be blank

Now I can get this if I do the following

=> error_messages_for 'user', :object => [@user.addresses]

but then I don't get errors on the user object like

=> Password can't be blank

Is there a way to tell the user object to drop errors it has on its
associations so I can do the following

=> error_messages_for 'user', :object => [@user, @user.addresses]

At the moment it will result in the first name being flagged twice.
# Addresses first name can't be blank
# Password can't be blank
# First name can't be blank