[PS][v6]MRP - rounding incorrect when using manufacturing efficiency

On OpenERP 6.0.3 with both web & GTK client:

I face an error when I launch a Manufacturing order with a manufacturing efficency of 0.9.

OpenERP orders 10% more of each components to make the final product. The system is ok when we have a quantity that have a decimal > 0.5 because the purchase order generated is rounded to the superior unit.

The problem appears when we have a number of component with decimal < 0.5. The purchase order generated is rounded to the inferior unit. So the manufacturing is never ready to produce.

Steps to reproduce:
- Install sales, purchase, mrp
- create one product to produce and two components (each are in MTO)
- Define a BoM for the product to produce with 1 components A and 3 components B
- Define a manufacturing efficiency = 0.9

- Create a manufacturing order for 2 product to produce
==> Components needed: 2.2 component A and 6.6 component B

- Launch the scheduler to have the purchase order generated.
- The PO generated is for 2 component A and 7 component B
- Receive the components

- Check the Manufacturing Order
- Run the production for the 2 units of the product

Problems:
- Sometimes you can't produce because you do not have enough unit in stock (2 units of component A instead of 2.2)

- Sometimes you can launch the production and produce but you will have one remaining line in the component to consume with a quantity equal to 0.
==> Impossible to complete the production (see screenshots)