gajim is a GTK3-based Jabber client featuring tabbed interface,
tray icon and notifications, encryption support, local link
(Zeroconf/Bonjour) and other interesting things.

As of the 0.16 version, gajim uses its own non-blocking xmpp
implementation called nbxmpp (python-nbxmpp on slackbuilds.org). This
is required to build.

For encryption PyOpenSSL is used, which is not required for building,
but produces a warning message on connection if not installed.