It seems that Limewire usually only connects to other Limewire ultrapeers and none of the other servents (Gnucleus etc). Does anybody know whether there's a reason for that?

thanks,

-frank

LimeWire is preferencing LimeWire ultrapeers, you can still connect to other ultrapeers with LimeWire but this is not necessary for leafs. LimeWire ultrapeers try to maintain connections to non-LimeWire peers to ensure that LimeWire is not disconnected from the rest of the network.