Bypassing Port Blocking?

[kutibah]

Anyone know how I can access a port that is blocked? Or re-direct traffic to another port? For example, I installed AIM on my flash drive. But when I launch it at my school, it cannot connect. This is because most schools block all ports except 80, and a few others. AIM uses port 5190. Is there any way I can access AIM by redirecting traffic through port 80 (http) or some other way? And I cannot use a web AIM because the only ones I know of, meebo.com and aim express, don't work through a web proxy. Any ideas?

P.S. If you can't help, but know of other Web AIM sites I can try other than meebo and aim express that would be great! Thanks!