Probably is. Port 23 should be open for you. I am not sure of which
client you are using but there are some open source ones available
which should hopefully allow for specifying web proxies. Again, you
need to try experimenting with these things.
I would have given a step-wise answer if I knew which client you were
using. I would have been more precise about the steps. I have all the
reasonsto believe that port 23 is not blocked. It's used for telnet.
It's __like__ ssh which wasn't and shouldn't be restricted from inside
IIT (like FTP is not). Probably somebody else can verify this. To
verify this yourself, google for you free telnet servers and try
connecting to them from your PC. Remember you need a client which
supports web proxy.
Once verified, just change the port to connect to in your chess client
to 23 and it should work (if this chess client supported web proxy).
Find a different chess ICS client (start from the debian repository)
which supports proxies.
I am sorry I can't be more precise about it.
SB