I have a jailbroken iPhone 3GS MC model running 3.1.3. I want to upgrade to IOS4 and jailbreak. I never downloaded 4.0 or 4.0.1, but according to Cydia, I have a saved 4.0 and 4.01 blob. I've read numerous tutorials which basically say to backup, restore to 4.0.x, then go to jailbreakme.com, but I don't have the firmware/ipsw file. Can anyone tell me how to get the blob from Cydia, or point me to a guide to do it? I've searched, googled and checked out Cydia to no avail. Thank you. I apologize if this post is in any way inappropriate.