try entering "localhost:5901' in iceweasel or your preferred web browser. If it connects then something on your Linux host is blocking external access to the VNC server..... if it DOESNT connect maybe make sure http access is enabled in tightvnc (cant be much help here as I havent used it)


" Is there any firewall issue at Knoppix end? If so, how to modify the rules? "

check the output of ` iptables -L ` for any active firewall rules.


Take Care,
-Justin
One Mynds Eye