Good news for all iPhone developer out there, Erica Sadun from TUAW has wrote iPhone v1.1.3 firmware documentation on her site. Erica said that there was no jailbreaking involved.
For those of you who doesn't no who the hell is Erica Sadun, well she's a PhD graduate from Georgia Institute of Technology majoring Computer Science. She is very passionate in writing, she have wrote and contributed about two dozens of books covering programming and technology.
You can read the entire documentation at http://ericasadun.com/iPhoneDocs113/