iPhone 3GS Jailbreaking problem

Hi, I got a 3GS for xmas and immediately jailbroke it with blackra1n, but whenever I reboot the phone goes into recovery mode meaning I need to restore the firmware. I tried making a custom firmware with pwnagetool 3.14, made it but itunes wouldn’t accept it and wouldn’t install it. Because I only just got the phone and it will be a newer model will I need the jailbreakers to release a new one? What is it I have which needs updating?
Answer #1
The jailbreak for the 3G[S] is tethered. That means that any time you restart it, you will need to reconnect it to your computer and run blackra1n again.
There is no way around this.