persist connection between servlet and applet

I wrote a socket-based chat program and now I need to run it from behind the firewall and the best way to do this is to use a servlet to facilitate communication between the applet (client) and the serversocket. The problem is that I cannot persist the connection between the servlet and the client. Obviously I can open the connection...send a message and receive some output from the servlet but I cannot keep the connection open to continue to send/receive data. Does anyone know a good way to keep this connection going? I also do not want to use 'keep-alive' as it is very unstable and unreliable. Thanks in advance.

[630 byte] By [uberallesa] at [2007-11-26 16:37:05]