Mobile Profiles

"Dont use Cell phone while Driving" is one common signage that we come across while driving. Apart from these are so many messages brought by service providers, handset makers etc on the harms of using a mobile phone while driving / riding. We have different profiles in the handsets which we can set according to different situations. We have General, Silent, Loud, Pager,Meeting etc why cant we have one more additional profile in the handset "Driving". So when we are driving we can set it to this profile so that whenever somebody calls there is a prerecorded voice which says " the subscriber is currently driving please call later". Is it too difficult for technology to incorporate this or is that nobody has thought about it. Will a Nokia,Ericcson, Samsung, LG,Motorola take note and see if this can be done