If you are using a college network, then they probably did block the IRC ports. You can easily find out by just phoning the IS/IT department and asking. Most colleges do block those ports. It is possible that they *may* be willing to unblock them when it's not during midterms/finals time periods. It just depends on the college. Asking won't hurt.
Also, be careful... most also have you sign an agreement stating that you're using the school network for school-related work (ie. not chatting, gaming, downloading, etc). If you did sign something along those lines and the college really wanted to be a jerk about it, they could disable your network access for the rest of the year, or even kick you out for violating that agreement.
Now, it's true that most won't do anything if you violate it. But it is definitely something to keep in mind. I had to sign one when I was in college, and I ended up being the 18th highest bandwidth user for the year and they didn't even say anything to me.
Just want to make sure you understand the possible consequences so you don't find yourself in trouble that you aren't expecting.