I cleaned up my files and tarred the results if anyone wants to give it a try ... I guaranty nothing. I can say that it runs on m MacBookPro 2 GHz Core Duo under OSX 10.4.10 with all updates. It has avrdude 5.4 with usblib support and was compiled under Xcode 2.4.1. It will burn an ATmega168 using an AVRISP MKii
http://www.wulfden.org/Arduino/bootloader-intel-usb.tar.gz
The tar.gz file is 275K and will unpack to 1.4 MB. It has the hexfile for the 168, the script, the executables, usblib support and man pages for avrdude. Unpack it into /Applications/arduino-0008, it will come out as a folder called "bootloader-usb". Go to a terminal window and cd to the directory and excecute the script by typing
./burn.command
I hope this helps someone
cheers ... BBR