I posted a message on your second thread concerning this subject:
http://daemonforums.org/showthread.php?t=9348
I note that some of the older FreeBSD images that are lying around various places are using an older u-boot executable that doesn't have the new cmd: bootelf. This is probably true of the August image you reference, but I'm not sure. The kernel is an elf-32, in most cases. The bootelf cmd makes the configuration less complicated (at least I think so). What you could do would be to build your own image, using the latest u-boot executable, or just use an OS image that already has it. The NAS4Free images all use the newer u-boot executable, and there are images for rpi, rpi2, and odroid. I've detailed this more verbosely on your other thread (mentioned above). FWIW, I have no affiliation with that project.
Note also I'm not personally vouching for those image's reliabiltiy or security facets. They seem pretty good, based on only a little usage. "Caveat emptor" always applies with all things, regardless of what project we're talking about.
Regards,
- Ron