no. you cannot upgrade/downgrade to anything but 3.1.3. which isnt jailbreakable on the 3gs with the new bootrom.
what jailbreak method did you use? if you used blackra1n or redsn0w, and had to rerun them every time u wanted to boot up. thats a tethered jailbreak, which is the new bootrom. some say that sn0wbreeze can jailbreak the iphone 3gs old bootrom, and the new version of pwnage tool is supposed to running 3.1.3. you cannot downgrade. if you've already used pwnage tool to jailbreak, you can restore with a custom firmware. the firmware can be 3.1.2. you cannot downgrade to apple's unmodified 3.1.2 firmware, only pwned.
Remember this thread you started?
What was so difficult about reading everyone's response in there that you had to start another thread?
no, you should not restore to the unmodified firmware. you should use pwnage tool 3.1.5 and use it in expert mode.
in expert mode, browse for the 3.1.2 firmware file wherever you downloaded it to. then click on the first block thing or whatever and go through all the crap. then when your done with that click build.
in expert mode, browse for the 3.1.2 firmware file wherever you downloaded it to. then click on the first block thing or whatever and go through all the crap. then when your done with that click build.
This didn't work. Thanks for the hope tho! : ) I'mm still at it... anyone have any solutions, PLEASE post! Thanx!