But I was really surprised, when I found that it's not the case. Author has used a Visual J# library (vjslib.dll) to read the zip file, which ships as a part of Visual J# Redistributable Package. Before a couple of years, I had worked for a few weeks in Java to help out a project and from that experience I knew that Java Runtime Engine probably comes with this kind of libraries to read .jar files.
It's a brilliant discovery, and serves a great purpose. By this functionality, one can download archived data from web, unzip it and process it to it's destination. Downloading data using a web-service and processing is very much possible using SSIS, but the missing bridge was unzipping files using SSIS without using 3rd party components. And now the bridge is ready !!
The library comes for free, and the author has published a nice step by step tutorial describing the implementation of the same. The entire article can be read on this link.