AJAX forms

Hi *,
I'm trying to build a form for editing user's accounts, and the problem I'm facing actually is how to add instant messengers accounts.
My idea was to use a link_to_remote to add a select and a text field every time the user adds a new account using AJAX, but I need a way to keep track of other accounts (a user has_many im accounts).
How do you people solve the problem of having an unknown number of similar entries inside a form and still having a clean params variable ?

TIA,
   ngw
Chiacchiera con i tuoi amici in tempo reale! http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com