As network technology is advancing at a rapid rate, clients can access information from the Internet using a variety of devices and via different types of networks. As the Internet is heterogeneous in nature, and with such diversities in devices, a client can use to access the Internet; it is impossible for a server on the Internet to contain information for all different types of clients. A possible solution to this problem is to use proxies to alter the content and to provide network enhancements to suit client's individual requirements. The current proxy-based solutions rely on a dedicated proxy server to provide the proxy functionality, but inevitably, this approach will fail if the proxy server does not have the necessary proxy functions, as a proxy server cannot obtain them from another source. We believe that it will be possible to overcome the above limitations of proxy-based solutions by making the proxies transportable and active, i.e. the use of proxy agents to perform the proxy functions. In this paper, we present the architecture of such a proxy agent system, and the implementation of a prototype to evaluate its viability.