This paper examines Java's suitability in creating real-time multimedia communications-based applications in Next Generation Networks (NGNs). We investigate some of the current enabling technologies provided by the Java plaiform which are concerned with the rapid development of realtime communications-based products and services. In particular, we look at creating a multiparty conferencing and collaboration service using the Session Initiation Protocol (SIP) and the JAIN Framework and present an approach which models multiparty conferencing applications by separating signaling and media transfer functionality. We map our model through the design stage to an implementation in Java. This paper is based on real experiences derived from work on an applied research project which is concerned with the development of a collaborative system which allows multiple distributed scientists to graphically analyse a common set of data obtained from mobile sensors in a virtual conference environment. Potential applications areas include education, emergency response services, gaming and any general collaborative application.