Bypass stealth proxy/accelerator

[sp33dy]

My computer is connected behind a university NAT/firewall. I suspect there is some kind of chaching web proxy in place...and it is making a thorough mess of my attempts to create an http tunnel to a proxy outside of the firewall.

I want to know if there is a way of detecting that there is indeed some kind of proxy in place...and more importantly if there are ways of bypassing it.

I am sure there is...but unfortunately being a networking noob I have no idea how to do this. Port 80 is an open port...but I beleive there is some kind of stealth proxy going on....

Any help is appreciated...