We do this using the 'Advanced' button on the checkin dialog now (with Merant, nee PVCS) but the 'Advanced' button is disabled when I set TFS as my SCC provider. Is there a switch we can flip on either side to enable this? Or do we need to write some custom extension? Or can I get the TFS changeset number to associate with the change in PB? Or am I coming at doing selective builds entirely the wrong way?