Flex commodity code for Inventory Adjustments

I am trying to flex in a category code from the item master F4101 (PRP1) to the managerial code 1 field in the F0911 for inventory adjustment transactions. I have set up the the cost type on P1620 and set up the flexible accounting using P40296. However when I post the Inventory Adjustment batch the managerial code 1 on the F0911 is not update with the category code PRP1 from the item master.