How do I figure out which ports are open behind a firewall?

I'm trying to get my BitTorrent client to work in school, but they have sealed off most of the ports. Especially ports for known apps like MSN, ICQ etc.
I could tunnel the traffic through a proxy server, but for what speed? :P

Anyone have any tips? I'm downloading stuff from sourceforge.net mirrors at 1.400kb/sec, so it would be nice to get a BitTorrent client to work here since I have my own portable HDD

Thanks for any help

Oh, btw, I'm using Slackware 9 and the Azureus BitTorrent client.

even if a port is open on your schools firewall, that specific port (eg 6881) needs to be forwarded to the pc that you are on.

as for a proxy server, azureus only supports tracker comminication via a proxy, so thats no real use either.

So I'm pretty f00ked then?
There's no workaround?

not if the network administrator is doing a good job...

=)

im sure there is, but it may involve hackin the server or something. lol i dunno im no expert, but ive thought about it a bit (my school download speeds are really good) and i cant really figure it out.

if you need to download things, try something where incommin connections arnt really important (like mirc)

my site http://www.cadj.tk is a small search page i made to find things on IRC,