It is now possible to include the Sold To and Broker addresses on Commercial Invoices. Currently this is enabled on a per-user basis in the Home | My Account | My Preferences page.
Checking this option will allow the Sold To and Broker addresses to appear on the shipping page.
Note that these addresses only appear for international shipments. Once the shipment has been submitted, the commercial invoice will include these additional addresses.
Note also that one must still check the Commercial Invoice checkbox prior to submitting the shipment.