Shipping prices, editing

In Maksujärjestelmät/kuljetustavat (paying, shipping methods) you can define the base price and the add rules by weight. Now you can only add or delete a rule, but it would be very nice and needfull to be able to edit = change the prices. F.ex. my rules are all the time the same, the same as the Post Office charges, f.ex. 50 g, 100 g, 250 g, 500 g etc. I only want to change the prices of different weighted orders.