By default, a prelink -afmR on a SPARC will break wget, which is obviously essential to the operation of emerge. Undoing the prelink on the wget binary will not fix it, but a global undo of prelink will. I'm guessing that it's one of the libraries it's dependant on. (admittedly, my experience with prelink is limited, so this "bug" may be safe to ignore)
Well, if I remember correctly, gentoo is the only sparc distrobution with prelink (only mandrake and redhat have prelink). Will try and replicate on my sparc box and see what goes wrong.
I have removed sparc from the prelink KEYWORD list as it isn't supported.
I take that this closes the bug ...