You will need an account with ADC (Apple Developer Connection) this is free and takes a few minutes to sign up, you should read the terms and conditions carefully and you should only sign up if you are thinking of developing applications in the future - http://developer.apple.com/mac/ Download the disk image IOUSBFamily-315.4-log.dmg for Mac OS X 10.5.5 Build 9F33 (yes, that is a 5 in 10.5.5 - this is a developer debug package of the USB kernel extension). Unplug non-vital USB equipment, such as external DVD writers, USB scanners, USB mass storage devices, at the most leave a Keyboard and Mouse connected. Install IOUSBFamily-315.4.1.pkg from within the disk image Reboot your system! Perform necessary DFU activity with QuickPwn or PwnageTool. Download the disk image IOUSBFamily-327.4.0-log.dmg for Mac OS X 10.5.6 Build 9G55 Intall IOUSBFamily-327.4.0.pkg from within the disk image Reboot your system! Reattach your USB peripherals.