I doubt it, - LimeWire isn't using the specified port for outgoing connections. It's just listening on that port for incoming connections. Only ultrapeers need the listening port to get connected.
For leaf-ultrapeer connections LimeWire uses random ports from the higher ranges (32768 - 65535).

I rather suspect that someone was downloading something from you and this took up so much of your bandwidth that you couldn't sustain your gnutella connections. - In that case going to tools->options->upload-> basic and moving the slider to the far left should help.

If an ISP is blocking p2p traffic, it usually takes him only a few bytes of the message stream to identify it. So you would be disconnected in a matter of seconds.

Some ISPs give connections to ports 8080, 80 and a couple of other ports a higher priority.

So you could fool primitive traffic shapers to give your traffic a higher priority if the remote host is listening on port 80. Many ISPs have already been using solutions like the one described in the article for a while, which allows them to give only verified web & email traffic priority.

sohow do you change your port setting.?

Changing your own port doesn't help you. You need all the other servents to change their ports to take advantage of a sloppy ISP giving priority to traffic from and to port 80. Your own outgoing connections come from random ports in the 32768-65535 range.

If your ISP is reducing the speed of your ports it helps - at least it worked for me with eMule (provider Tiscali). My download speed increased from 3kb to 60kb...

Morgwen