One of the goals of the integration of formal and graphical methods is to reuse tool support associated with formal methods. This paper reports on a combination of the Jaza Z animator with the RoZ tool. RoZ produces a Z specification from an annotated UML class diagram. It also generates the specification of basic operations associated to the diagram. The paper recalls the principles of the RoZ tool, gives a typical animation session, and discusses how RoZ and class diagrams must be adapted to support animation.