In his email he states:
There is a very minor release of Zip-Ada (basically, the command line tools work better!)
Zip-Ada, in case the name doesn’t give it away, is of course a library that enables you to work with Zip archives. You can Zip, Unzip, ReZip, compare Zip archives, search Zip archives for a string and decompress BZip2 archives. All from one library with _no_ dependencies.
Zip-Ada is available on an impressive range of operating systems.