Google Checkout and perweightunit shipping

Does Google checkout work with perweightunit shipping? All my orders through GC using this shippping method come out with zero shipping costs, whereas orders using PayPal all show the correct shipping value.

I checked the GC logs and its sending the shipping like this:

<shipping>

      <flat-rate-shipping-adjustment>

        <shipping-name>Perweight Unit: Perweight Unit</shipping-name>

        <shipping-cost currency="GBP">0.0</shipping-cost>

      </flat-rate-shipping-adjustment>

    </shipping>

and the item information is being sent like this, with the item weight showing the postage value:

 <item>

        <item-weight value="7.95" unit="LB" />

        <item-name>Vision 42" SR Bodyboard</item-name>

        <item-description>[Colour:Black] </item-description>

        <quantity>1</quantity>

To me these seem to be the wrong way around. Anyone else seen this?