When I typed
kldstat
it loaded ng_ubt.ko
>dmesg
ubt0: <vendor 0x0a12 product 0x0001, class 224/1, rev 2.00/48.39, addr 2> on usbus0
>sudo /etc/rc.d/bluetooth start ubt0
/etc/rc.d/bluetooth: ERROR: Unable to setup Bluetooth stack for device ubt0
How can I solve this problem?