O2 Xda11 and hands free function

My O2 Xda11 bluetooth phone recognises the Hands Free function in my Prius, but the Prius does not appear to recognise my O2. Is there a solution here? I'm sure I met someone ages ago who had an O2 cell phone and his worked quite well with his Prius.

 

I have indeed attempted to pair the phone and hands free unit. My phone gives me the usual acknowledgment that it has "discovered" the hands-free function, but the Prius does not acknowledge in return. We have only just acquired the car, and we will bring the subject up with the dealer when it goes in for its one month check-up. I'm just not all together confident that they will know how to fix this problem.