Reversable Jail Break for iPhone
 

Easy way to jail break your iphone (go to Europe and use SIM card there) and when return home or if need warrenty work, reverse.

www.jailbreak.com then follow instructions.

To reverse, hook to itune and "restore"

Cannot be system 4.0.2 or later (must be 4.0.1 / 3.2.1 or earlier)

If newer system, google PwnageTool or SnOwbreeze or redsnOw.
I have not used them and don't know if they are reversable.

Note. Current US Law oks jailbreaking. Just screws your warrenty, but with this you can restore to natural

all jailbreaks are reversible, you just flash a stock firmware.

the only issue is if the phone is dead enough that you can't do anything at all, including flashing a new firmware. apple can potentially figure out if it has been jailbroken, depending on how dead it really is.

I find the problem that it is too easy to lose your jailbreak. I configured my iTunes not check for firmware upgrades and with the newest version seems to still spot that I am using old firmware and starts pushing me to change the settings so that I can do an upgrade. I have a jailbroken copy of 4.02 and so far haven't been tempted to go to 4.2 since it looks like the jailbreak for 4.2 is still a tethered jailbreak.

which iphone do you have? If you use pwnagetool to preserve your baseband, you should be fine, Stu. Just don't ever restore or let itunes do the stock upgrade ever again. (assuming you have a suitable older baseband that's in the list on the dev team's blog page).

The current method, for people that haven't preserved their basebands, (including those that buy new phones) involves using an ipad baseband, and if you do that you can never go back to the stock firmware. So if you have the older baseband, you can use pwnagetool to build a custom ipsw which will include your old "safe" (or vulnerable) baseband and do a restore using that custom ipsw.

Also keep saving your shsh blobs via tiny umbrella and/or cydia.

-David

I have a jailbroken 3gs with 5.14.02. I accidentally upgraded my phone to 4.1 with the new baseband. My SHSHs were backed up and I downgraded my firmware and eventually wound back up at 4.02, but think I'm stuck on the baseband. I'm aware of the iPad firmware trick, but I'm a little nervous going there. Incidentally, it will be curious to see whether Apple leaves these people stuck or modifies its next upgrade to restore the phone to a kosher base band. I can see a heated fight in Cupertino which is the best strategy. A third one will be a pay restore service where they make the owner crawl to their Apple store for a "fix" knowing that these folks are unlike to stray from the farm again.

Right now, nothing seems compelling enough with the new upgrades to worry about this which leaves me with my stand pat strategy.