q: belongs_to & build

hi

invite <belongs_to> location
location <has_one> invite

background: location is not set at the time of the invite...

i = invite.find(1)

how do i build the location and update the invite (location_id) in

one go? (build doesnt set the foreign key for me..)

loc = i.build_location(:title=>'test')
loc.save!

create a location, but fk is missing...

thx