iPhone Interface with Bluetooth Headunit

[2007TBSS]

Anyone else have any troubles with this? The JVC AVX840 interacts with my Android perfectly. While the music is playing, I hit phone on the H/U, touch the screen to select who I want to call from missed calls/outgoing calls/phone book, make a call end call ect without even taking the phone out of my pocket. With my wifes iPhone 4gs, I have to stop the music, go to the Bluetooth option, make the call though the H/U, then select JVC H/U as my audio source on the phone to get the call off the phone and into the cabin speakers, then talk, then hang up on the H/U, then end the call on the iPhone, then select USB to listen to music again.

Are there settings I am missing? Is this just standard Apple nonsense? Why is a top of the line phone such a pain in the ass for a standard option such as Bluetooth??