ok, here is one case. Lets say; like in my case irc is blocked. hmmm! easy ey change port? No its not just port blocking. In my case its blocked at the protocol level. the firewall filters all traffic and looks for any irc stuff. this makes it impossible for you to get in even using a BNC. so now what? here is one solution.
if you have a shell account else where, then this is no hard job. Maybe you can ask a friend to give you one. anyway, here is what I did
ssh -L 6667:eu.undernet.org:6667 yourshell.com -l user
where yourshell.com is where you have a shell account access. once you do this, you'd be asked for the password and now you are having an established connection. now what's next? Simply run xchat and type /server localhost. so what's the point? well on a shell too you have things like BitchX; but not a GUI client running locally. thats it. enjoy.