java.net.SocketException: Broken pipe

This happens when you write to a TCP connection that has already been closed by the reading end. Depending on your application, you would either treat it as an application protocol error or ignore it and give up. In either case the socket is almost certainly dead and must be closed, and the client session abandoned.

Reference:
http://forums.sun.com/thread.jspa?threadID=5218565
http://www.flukenetworks.com/fnet/en-us/supportAndDownloads/KB/IT%20Networking/protocol%20expert/What_are_TCP_RST_Packets_-_Protocol_Expert