I am not sure if it applies in this case, but I know that with my logitech blue tooth mouse and keyboard, I have the option of just using them out of the box, or paring them up using some magic and digital glue. The problem with the pairing is that if either of the two devices lose battery or get reset, then neither can connect until the paring process is reapplied. Is this an option with your blue tooth device and are you using it? Also, you may want to consider implementing a timeout. What I mean by this is if after a certian period of time nothing is sent to or from the chip via bluetooth, shut it down. Now that I think about it, that might not be practical, but you could attach that behavior to a button, either the on board or an external one, that gets pressed just before shutting off the Axon that will deallocate your BlueTooth, hopefully freeing up the port on your pc.
Although I might not know a damn thing about using BlueTooth with AVR, hopefully this might spark an idea in your head.
Mark