The lack of this feature is a big deal for me. I have a need to for loud, long tones for SMS messages when I am on call. The only way for me to do this now is via a team phone. It's a pain as setting need to be updated every time I receive it.
So many things keep me wanting to jail break my phone. This is just another example of lacking features that Apple could easly address. Not complaining (much) really like the iPhone, but still....