I installed 4.0.8 Pro on my box running Gentoo linux. I have also tried the beta as well as older versions of Limewire and run into the same problem. The client has great difficulty connecting to other hosts. It -only- seems to be able to connect to hosts running Bearshare, and is not able to maintain a connection for very long (less thana minute). No searches return results, ever.

The router which this machine is behind is not blocking Limewire traffic. I have Limewire running on several other computers on this same network, and they function just fine.

Edit: I'm on a cable modem connection with 4mbps down/256kbps up