Currently I have installed OpenERP 7.0 on a Ubuntu 12.04 server

We buy the products we sell in Kg The bars of 6 meters. The relationship between Kg and bar is always a number with a decimal number, not a simple relationship of 6 UoM = 1 UoS.

In the product line select the product and then put the amount in UoS. But this did not update the amount UoM. And I have, in the UoM change the unit type for the value is updated.
Is this so? Because it becomes a bit cumbersome.

Thanks for any help you can give me.