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.
v4.1p1
Dave Mack released a patch to his unofficial update to the comp.sources.misc group here:
https://groups.google.com/d/topic/comp.sources.misc/dov5AFo1rDI/discussion
You will need to install the v4.1 release first and then apply this patch to it.