Need to call account generator for each line on a requisition even if the item is same on both lines

Hi All - i am trying to do a customization to call account generator for each line on a requisition even if the item is same on both lines. where would i need to do thee customization? currently, it looks like, the account generator itself is not called for second line if the item number is same as first line and it copies the charge account from first line, but i want to create a new account for each line based on a custom attribute. has anyone done a similar customization, if yes could you please share the details?