Notcom, the developer behind TinyUmbrella, has just updated and released TinyUmbrella 4.21.04 to save your SHSH blobs for iOS 4.3 beta 2 or iOS 4.2.1.Earlier, version 4.21.03 was released by Notcom for the same purpose, but as it had some bugs, he fixed it and released the TinyUmbrella 4.21.04 version now.
This is what he said in his blog :
I’ve just added iOS 4.3b2 support. For those of you with Apple Developer accounts, this means you can save your SHSH’s for that version and restore to it permanently.
For those who don’t know what’s the importance of saving of the SHSH blobs, actually it allows you to downgrade your firmware to a lower version. It is important in case if you accidentally update to a iOS firmware version that can’t be jailbroken, as Apple prevents this otherwise.
Download TinyUumbrella 4.21.04 to Backup SHSH blobs for iOS 4.2.1 /4.3 Beta 2.