In this paper we present a semantic interpreter which implements a dynamic denotational semantics for a small experimental concurrent object-oriented language that we call JoPool. JoPool embodies the modern communication abstractions introduced in the join calculus. It provides the communication primitives of join Java and polyphonic C# together with a generalization of the rendez-vous mechanism that is typical in Ada and POOL. The semantic interpreter is designed with a continuation semantics for distributed computing, introduced by us in previous work. As an implementation tool for the denotational semantics we use C# 3.0 lambda-expressions. As far as we know, this is the first paper that reports a compositional semantics for the communication abstractions of join Java and polyphonic C#.