The software that came with the XOOM USB Bluetooth Class 1 adapter that I picked up, last week, has a sync service listed on the interface. Don't use that, so not sure how well it works. It also has services for printing, pushing, etc...
Picked it up, at Microcenter, for 25 bucks.
Edit: I just looked in the BT options, on my Curve. There is no 'Sync' service listed. Closest thing seems to be 'Desktop Connectivity'. Not sure if that includes syncing.
If you have paired your BB with your decktop. You can then within DTM under options/connections setup BT. Make sure connection is selected for BT. Once you have confirmed pairing it should sync. You may have to do a battery pull but it works for me. You should be able to sync then.