The java version proved to slow in the end, in addition to many windows users not actually having a java runtime installed. As a result, work was done to port it to c++. At the time, vypress was also found that worked rather well, so mirvChat went on hold. After a long time, it was decided that a cross-platform version of vypress would be kind of cool, so after looking at gui toolkits, mirvChat v2 was created with the FOX gui toolkit.
This proved to be simple enough. Still a fledgling c++ programmer, looking back at the mirvChat v2 code shows that, but it worked. This remained and was improved upon through several version upgrades, to version 3.4. After that, work was halted and it was deemed "stable enough"; besides all else, anyone using it had long since moved on to other programs.
But, with other programs unsuitable to the networking environment on which all this has been programmed, recently the idea of mirvChat was resurrected. It has been written entirely from scratch, including the networking code (it now uses Unix sockets directly, instead of the Hawk Networking Library as was done previously), but still uses FOX (that is a fast, reliable, useful library - why change?). File sharing has been included, but there are no longer topics or different channels. Messaging is present, and other features, but it's a vastly simpler interface now.
A source zip file is provided, and win32 binaries are also provided in a zip file. Source tarball will be included shortly.
Visit the sourceforge project page here.