When I found this treasure map, it reminded me somewhat of another of IB's treasures, in which he had posted two base64-encoded paragraphs, and asked solvers to pick the correct one. Base64 is the MIME encoding, similar to uuencoding, but with a different character set and a different encapsulation scheme.
Anyway, I decoded the text on this basis and that's what it said.
Incidentally, when I looked, I found a file in my acka directory containing this map; I must have been feeling particularly uninspired when this was posted, to have started on it and not solved it.