Unfortunately I still was not able to get dfu-util working properly under Mac OS X. But at least I can work around the problem. Here a small resume of the workaround:

  1. Boot the Openmoko into U-Boot (AUX+POWER)

  2. Plug in the Openmoko via USB

  3. Execute the dfu-util command you want. To flash the rootfs execute:

    dfu-util -a rootfs -R -D rootfs_filename.jffs2

  4. You will get an error like: _Cannot set alternate interface: usb_setaltinterface: could not set alternate interface

  5. Unplug and replug the Openmoko, you should now see a message like this on the Openmoko screen: DFU: Switching to DFU Mode

  6. Now execute the command again, and this time is should work.

    dfu-util -a rootfs -R -D rootfs_filename.jffs2

It’s not really what I want but it is currently the only way for me to flash my Openmoko