iPhone 4S Bluetooth compatibility?

When I read reviews about iPhone 4S they say it has Bluetooth 4.0 and then they specifically state it is backwards compatible (which all Bluetooth versions have been by the way so I thought that was an odd statement for them to make). However none of my Bluetooth devices work with the iPhone 4S. My other devices can pair up but the iPhone refuses to connect with them.

I have a Sony Ericsson Satio which when trying to connect produces a message on the iPhone 4S saying the other device is not Bluetooth 4.0 and so it is not allowed to connect. I also have a Zenec car multimedia system and that too can pair with the iPhone 4S and again the iPhone 4S refuses to allow the connection to be made afterwards.

Does anyone know why Apple have put such strict restrictions on the Bluetooth feature and if they will relaxing these rules because Bluetooth is supposed to be open, but it appears it is very closed. The example of the Zenec is a little worrying, I can no longer do hands free in my car as a result if I continue using the iPhone 4S.

I have had Nokia's, iPhone's (past models), Sony Ericssons, HTCs and Samsung's connect to these devices without any problems, but that message on the iPhone 4S appears it is designed to be like this. Anybody else had this issue and found a way around it, or as stated above... will Apple be opening up the Bluetooth in a firmware update?