bittorrent limit download rate

[newsletter]

Is there a way to limit the download rate with bittorrent?

When I start the torrent the download rate immediately jumps up to max out my 
bandwidth.  With bittorrent running, web pages don't load and my email client 
times out trying to download mail.  If I stop bittorrent, everything works 
fine.  Unfortunately, my firewall/router doesn't support limiting bandwidth 
by port.  I've tried setting the --max_upload_rate  to low numbers but it 
doesn't seem to adjust the ratio.

I would cancel the download and just use ftp but I've been starting and 
stopping this all day and have about 40% of the DVD iso downloaded.  I don't  
really want to start over and figure I have another two days of stopping the 
process when I need to get work done.

Thanks, 
Ryan