Help with Payables, Revaluation, etc by product

[Gorann]

I have a issue, if any of you has an idea please help me:

One customer needs all his paybles, receivables, revaluations allocated by product and product is one segment of the accounting flexfield.

For example in AP when I enter an invoice, i enter the ITEM line and an account, the tax line (code tax account) and the Supplier account its a parameter of AP that can be setup in module level, vendor o site vendor. But what i need in reports and in the report balance sheet are suppliers by product. I research en little bit, and i found the offset functionality but it doesnt work, because the AP offset open the supplier account in the same way that de Item line and we don