(You may want to consiser using nzmqt instead - it's a cleaner implementation and is based on newer versions of the underlying API)
Zeromqt integrates ZeroMQ (version 2.1.0 and later) into the Qt event loop, mapping ZeroMQ message events onto Qt signals.
It also provides an API that is more "Qt-like" than the native ZeroMQ C or C++ APIs, allowing messages to be handled as QByteArrays and providing classes that are similar in style to QAbstractSocket.
There are no known bugs, but nor has there been any testing beyond the included sample app. It's being used as part of a large commercial application, though, so it'll be getting some testing and attention.
To use Zeromqt in a Qt project, add this to the projects .pro file
HEADERS += ZmqException.h ZmqMessage.h ZmqSocket.h ZmqContext.h SOURCES += ZmqSocket.cc ZmqContext.cc LIBS += -lzmq
and copy the six Zmq* files into the project.
Zeromqt uses C++ exceptions by default. You'll need to catch ZmqException objects in the normal way (which on Qt probably involves inheriting from QCoreApplication and reimplementing notify()).
There is untested support in the code for replacing exceptions with Qt-style errorString() error handling instead - look for USE_EXCEPTIONS
There's a single pub-sub sample included. Build it with qmake; make. Run the server with "./pubsubsample server foo" and the client with "./pubsubsample client foo".