Peter Jannesen released an unofficial update to Dave Mack's release as version 4.2 to the comp.sources.reviewed group here:
https://groups.google.com/d/topic/comp.sources.reviewed/9Cn4WTNOeoo/discussion
He renamed to (n)compress to avoid further confusion among users.
Execute the two scripts in order to extract the files in your current working directory.
You will need a POSIX shell, sed, and shar to install.