The infamous iPhone Dev-Team strikes again! They have found an old exploit(24Kpwn) which is still present in the bootrom of iPhone 3GS and can be used to jailbreak and unlock iPhone 3GS. So those of you with the latest Apple hardware wont have to wait for too long before you can jailbreak and unlock iPhone 3GS by using ultrasn0w.
Some users who have recently updated/restored to the new iPhone firmware 3.0 have reported to have got into a problem where their phone randomly doesn't ring when there is a call nor does the keyboard or slide to unlock button sound anymore. I got into this problem as well after unlocking and jailbreaking my iPhone 3G with firmware 3.0, my iPhone suddenly stopped ringing on calls randomly, resulting in missing a lot of important calls.
I have received loads and loads of emails regarding all the issues people are facing when trying to unlock and jailbreak iPhone OS 3.0. I have tried my best to answer them by email, and to all the comments in my guides here and here. Here is compilation of all the fixes for the issues that you may be getting when unlocking and jailbreaking iPhone OS 3.0 using ultrasn0w.