iPhone 3GS NewBootRom on 4.0.2

[Chint]

I recently purchase a Mint iPhone 3GS. I am not aware whether any Jailbreak was done before.
f0recast shows me this::...

What should I do for Jailbreaking it....

[Orby]

Currently you cannot jailbreak that device at all.

The serial number (85017...) tells me it was made during the seventeenth week of 2010 (week of April 18th) and therefore cannot have the prerequisite SHSH blobs that f0recast is referring to on file (the blobs it's referring to, 3.1.2, stopped being signed on February 4th of this year).

Since the device is already on 4.0.2, it cannot be jailbroken as-is.

If by some miracle you have SHSH blobs saved for 3.1.3 (which that device must have shipped with), 4.0, or 4.0.1, downgrade to that firmware using x98car's tutorial on this forum and use http://www.jailbreakme.com/_/iPhone2,1_4.0.pdf , http://www.jailbreakme.com/_/iPhone2,1_3.1.3.pdf , or http://www.jailbreakme.com/_/iPhone2,1_4.0.1.pdf depending on what version of iOS you are able to restore to.

Please note you must have already saved the blobs with TinyUmbrella or by having the phone previously jailbroken and had asked Cydia to save the blobs for you. If you do not have blobs on file with Cydia now, you cannot get them, and therefore cannot downgrade.

Regrettably, the new greenpois0n tool will NOT be able to jailbreak you currently. Unless you've got 4.0.1 blobs or earlier, you'll have to wait for a new jailbreak, no ETA on one.

[Chint]

Thanks... but wont sn0wbreeze be of any help to me...!!!

[bellyfrog]

snowbreeze only works on old bootrom phones, and only when they have been pwned on an earlier firmware.

Your only option is to downgrade, if possible.