Specifies the path and filename of the boot image to be used when making an "El Torito" bootable CD. The pathname must be relative to the source path specified. This option is required to make a bootable CD. The boot image must be exacltly  the size of either a 1.2, 1.44 or a 2.88 meg floppy. It is assumed that the first 512 byte sector should be read from the boot image (It is essentially emulating a normal floppy drive). This will work for example, if the boot image is a LILO based boot floppy.
