[ic] Additional fields of basket item

[vincenker]

I guess that Interchange saves my basket item fields into cookies. These
fields may 
include sku, quantity and price. Now, I want to submit some more
customized fields when 
a user put an item into the basket, e.g. user additional remarks for the
specified item.
I¡¯ve gone through files like cart, log_entry, log_transaction and
order.profiles, but still 
don¡¯t know how to do this. 
Could give me any direction? Thanks a lot! :)

Vincent