jGGTrans is a gateway between Jabber/XMPP and Gadu-Gadu (which is a very popular proprietary instant messaging protocol in Poland). It allows Jabber users to use their favorite XMPP client to talk with their GG-using friends.
Open source project that offer summary and download services on this page is a project that carry out their development work on other open source development sites. Their work is linked to this page via a feature called OFI, and their work is not carried out here on OSDN site.