Vagrant Multiple VM Provision Order

Question

I'm trying to build a vagrant file that defines multiple VM.

Vagrant.configure("2") do |config|
   config.vm.define "one" do |cfg|
    [...]
   end
   config.vm.define "two" do |cfg|
    [...]
   end
end

My problem is that after the machine "two" is created and running, I want to run another script in the "one" machine. I have tried with the experimental 'after" function, but I may use it in the wrong way.

Is it possible to do this with a pure vagrant script? (if true how ? :) )