Ubuntu Transmission Bittorrent Client Add To Startup Ubuntu Torrent Problem?

Ubuntu Torrent Problem? - ubuntu transmission bittorrent client add to startup

I have Ubuntu 7.10 ISO that I) in all haste by the transfer (and as BitTorrent. The problem is that when I start the seeds in the transmission gives me the message that I I can not access the tracker.
I use Ubuntu most tracker http://tracker.ubuntu.com:6969/announce

Please tell me what I need, I want to help and seed.
If there is still a very common tracker let me know too, or if I'm wrong in the past. Thank you.