Hi Marcel,
virtualbox and then running either usbmon or Wireshark on your Linux system should work just fine.
O.K., here's what I found: running windows in virtualbox first then shutting it down again: the adapter works in linux too until the next reboot (still have to load the module and echo the ID to new_ID because of the adapter not reconigzed by the actual bt module) Doing a capture with wireshark on usb port 2 gives me the capture file attached.
Harvey
Attachment:
cap_BCM20702A0
Description: Binary data