DFU mode is needed if your iPhone is never pwnaged (used PwnageTool or Quickpwn) before whenever you want to jailbreak and or unlock it. For those already having pwnaged their iPhone further action only needs simple recovery mode.[EDIT 2009-05-13
As predicted by the Dev Team, missing option to use DFU mode in Mac OS X 10.5.6 has been a bug. It is fixed now in Mac OS X 10.5.7. Use the internal Software Update function and update to 10.5.7 and you'll be able to get into DFU mode again.
Download and install the update
Mac OS X 10.5.7 Update
or even better the combo update
Mac OS X 10.5.7 Combo Update
and you will be set.
No more need for the Automator based fix in 10.5.7. I have un-stuck and closed the thread.
Mac OS X 10.5.6 was released on December 15th, 2008. It disables recognition of a device (like the iPhone) in DFU mode. It is not known if this is intentionally disabled by Apple or just a bug. The iPhone Dev Team believes "this behavior is due to a kernel bug not a specific countermeasure by Apple."
All credit for the solution goes to the iPhone Dev Team - as usual, I have just developing this easy to use app!!!
One solution ist to replace two plugin kexts with the ones from Mac OS X 10.5.5 and then rebuild the kextcache. This innvolves some knowledge of the system and heavy use of the application Terminal.
This is where the Automator programm Fix_DFU_10_5_6 comes into action. I put it together to do the complete job with one mouse click. The user has to be logged into his Mac with administrator privileges (usually the account you used while setting up your Mac) and has to provide the admin's password.
The programm then:
1. checks if you are at Mac OS X 10.5.6 or better (if not will quit)
2. show a readme
3. quits all running apps (with save option)
4. backup the original files (AppleUSBHub.kext and IOUSBCompositeDriver.kext from 10.5.6) in a new folder on your Desktop
5. ask for your admin password
6. copy AppleUSBHub.kext and IOUSBCompositeDriver.kext from 10.5.5 into the desired location on your Mac
7. set owner:group and permissions
8. rebuild the kextcache
9. reboot your Mac
Right at the end the programm will tell you that the cache is beeing rebuild, just let it do its job.
Your Mac will automatically reboot when done - DFU is enabled then.
[EDIT Dec 22] hack0 members abrasBR and Olympios have tried the solution on unibody MacBooks (Pro) at firmware 10.5.6 and had success! After applying the patch their unibody Macbooks were able to establish DFU mode with the iPhone. I got a shiny new Macbook unibody 2.4 GHz, the patch works without a glitch - check post #49 in this thread on how-to. [END EDIT]
How-to (see pic below)
Download the package (zip-archive) at
Unzip the archive (pic 1) and place the folder "Install_IOUSBFamily_kext_10_5_5" on your Desktop (important). Open the folder and start the Programm "Fix_DFU_10_5_6" (pic 2).
You will see the Readme box (click "OK") (pic 3), then you have to provide your admin password (pic 4). The programm then will do its job.
At the end the Finder will open another dialog box telling you that the cache is beeig rebuild (pic 5). Klick "OK" or just leave the box alone. After a couple seconds your Mac will reboot automatically - done, DFU is enabled again.
On the Desktop you will find a new folder called "Backup_IOUSBFamily_kext_10_5_6", it contains the two 10.5.6 files
Hope this helps,
p.s.: If you are interested in the Automator source, just drop me a pm with your e-mail address