Caputring MAC ID of HHT while accessing asp.net thro terminal services.

                              we have developed a application with asp.net and we have deployed in the windows 2003 server. This application is accessed by HHD (Motorola Hand Held Device).
                             Thro terminal services, HHT is connected to our application. Here how can i capture the MAC ID of HHT.
                              Please help me.
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