If using another port doesn't work in mIRC, it will not work in any other client. If you try using a port and it tries to connect and fails, then it just means that they blocked it. Perhaps they only blocked 6667 to begin with and after you used it on 7000, they noticed and chose to block everything.
Remember that if you try to get around a block that they purposely put in place, you risk disciplinary action from the college/university that may include being banned from their network and/or being expelled. Be careful what you do that you know they don't want you doing.
