Issue with work order account and IO (scrap)

I have the follow issue:

1 - A work order is generated normally

          Qty ordered: 1000

2 - Part list and routine are copied normally.

3 - The materials are issued normally in P31113.

          Qty necessary: 1000 + 10% scrap

          Unit cost: $10

          Total amount: 1100 * 10 = $11000

          Total issued: 1100 units

4 - The scrap is registered in P31116.

          Qty scraped: 100

5 - The work order is concluded.

          Total A1 = $10000

          Total A2 = $1000

          Total (B1...B3) = $500

          IC = $11500 / 1000 = 11.50 per unit on F4111

6 - Here starts my problem... At this moment, my F3102.CCUA is

          A1 = $10000

          A2 = $1000

7 - When I run R31802A in final mode, my F3102.CPAT is updated to:

          A1 = $9000 (????)

          A2 = $1000

So, at this moment, I have a difference between the IM accounted amount and IC accounted amount.