(please someone correct me if I'm wrong)

This is a patent issue with Unisys. Refer to http://www.faqs.org/faqs/compression-faq/part1/ and seek to "(c) LZ78" to find the relevant section. GNU gzip and zlib was created as attempt to work around the patent issues. As I recall you /might/ be able to get away with just creating a decode routine but an encode routine would certainly infringe on Unisys' patent. It's a pain but just use the binary compress/uncompress programs.

__SIG__
use B;
printf "You are here %08x\n", unpack "L!", unpack "P4", pack
  "L!", B::svref_2object(sub{})->OUTSIDE;
[download]