Call them and ask them yourself.
Seriously.
Try and sound as "innocent" as you can and ask them if they block p2p trafic.
Of course, don't ask them about ways to get around this (if they do throttle P2P).
You can try changing the port. (do you have a firewall or a router?)

__________________
iMac G4 OSX 10.3.9
RAM 256MB
LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

"Raise your can of Beer on high
And seal your fate forever
Our best years have passed us by
The Golden Age Of Leather"
-Blue Öyster Cult-