I assume "chicken" is Chicken of the VNC", a very popular VNC client for the mac. If you are able to VNC into the computer in question but not out, you should look at the situation on the other end you are trying to connect out to. Your local mac may either have the ports mapped properly or be using uPNP to map the incoming connection. If that's not set up or set up poorly at the other end, it would prevent your connecting out from your computer, INTO that other computer.
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