One way you could do this would be to store the page that you want the user to go to in the users record or in the user level record. Then in the authenticate user server behavior you could create a session variable based on the page for them and use this session variable as the redirect value for the login.
In the end this should allow the user to login, set the page they have listed as a session variable, then the redirect in the authenticate user server behavior will make use of this session variable to send the user to the correct location.
This is all higher level info, if you need some more details about any part of this post back with some specific questions that you have and I will help you with what I can.