Bluetooth automatically dialling when engine is switched on

Hi, I'm new to the forum so I'm not sure where to post this - feel free to move the post to the correct place!
I have a 2006 HSE Range Rover (L322?). When I turn the engine on, the car automatically dials the last number I have dialled on my phone. I have just been given a brand new iPhone 4s by the Apple store as they thought my old phone was the problem - it isn't!
Has anyone had a similar problem?

tell your butler to behave himself.

haha, as if that little virus is still floating around... wrote that years ago