How To Block Limewire Ports Using Linux Firewalls
Blocking the P2P (peer-to-peer) application 'Limewire' is easy using a Linux firewall, IpTables and the Rope module. Since Limewire is a Gnutella client, it can be blocked using the same techniques as for any other Gnutella client.
Blocking Limewire and other Gnutella clients cant be done by simply blocking a range of ports, because it can run on any port the user selects. This is where the Rope module comes into it's own : it can identify the protocol based on the contents of the data contained in the IP packets being exchanged.
See BlockingGnutella for the detailed how-to.