I'm trying to perform an upgrade of a SharePoint 2007 environment to 2010. Our plan is to move to entirely new hardware and do a content database migration. In such a scenario, it seems that BDC application definitions are not upgraded as part of the process. Also, it seems that the 2007 app definition file format is not compatible with BCS. In an in-place upgrade I understand that these settings get migrated as part of the upgrade process. Is there any way to access the upgrade facility, either through a utility or even via the API to perform the conversion?