Payments applied to specific AR invoice line items

[Jeff Kowalczyk <..hidden..>]

Fielded a question from a branches/1.2 user who needs to reference a
specific line-item when applying a payment. Typical of Insurance-paid
goods and services, The initial payer is the customer. Third party
payments come in later from multiple payers and on multiple sources (check
number).

My first reaction to the question was to use the memo field to refer to
the invoice line item line number. Additional automation could be used to
populate the memo line based on that line item line number reference.

Unfortnately, line item line number is not in the invoice table. It
appears to be a UI implementation detail.

Can anyone comment on the trunk's state of the art with respect to
applying receipts to AR? A screenshot would be very much appreciated.

Thanks,
Jeff