Does the Bluetooth version of my phone and Philips headset need to match?
No, e.g. a headset with Bluetooth version 2.0+EDR can work with a mobile phone with Bluetooth version 1.2, although some of the advanced features of the newer Bluetooth version may not be used. However to work successfully both devices need to support the same profile, e.g. to stream music over Bluetooth both the headset and the mobile phone need to support A2DP.