Marketpress by-weight shipping for multiple quantities

It appears that in 3.0.0.5, when using the Weight Rate shipping calculation for shipping method, products with multiple quantity do not calculate weight for each item.

For example, if I'm selling widget x which weighs 1 pound, and I try to order 10 of them, it calculates shipping based on a 1 pound weight.

If widget y also weighs 1 pound, and I try to order 5 of widget x and 5 of widget y, it calculates shipping based on a 2 pound weight.