jailbreak iphone 4 iOS 4.0.2

[beanz]

Hello, I have IPhone 4 with iOS 4.0.2 installed on it. I have been looking all over the internet on how to upgrade to iOS 4.1, and have had no luck at all. I have downloaded the iOS 4.1 ipsw file, and tried manually updating, but iTunes tells me that my iphone is "incompatible with the firmware file". I an scared to update to iOS 4.2, the most current iOS because i havent seen anything on here about jailbreaking it ( only for 4.2.1) is there any way I can possibly update to iOS 4.1 even though 4.2 is only available to download?? I have tried to update to 4.1 using tinyumbrella to preserve my baseband, but of course this is impossible for me because it cant get the SHSH blobs, whatever the hell those are. Any help would be appreciated.

 

[iGaz]

You can only upgrade to 4.2.1. You won't have SHSH blobs saved for 4.1. If you save your SHSH's for 4.0.2 before upgrading you will be able to downgrade back to that.

4.2 is 4.2.1 as far as jailbreaking is concerned. If you wish to preserve your baseband (remember baseband is for unlock only) then you need a custom ipsw created on a mac....