Please take Wondering Why's advice here.
Try installing PeerGuardian, it will help keep the fake hosts out...Remember to enable PG just before you start limewire up...
Phoenix Labs » PeerGuardian 2 If you're using Vista, there's this PG2 Beta available for Vista users.
PeerGuadian 2 for Windows Vista beta released - Phoenix Labs PeerGuardian 2:Manual - Phoenix Labs Wiki
Another thing if you are using limewire 4.13 and later you can apply this hostile list...
The TechNutopia Fullsize Hostiles List for BearShare and LimeWire