uggggh im having the same problem.

OS: Win XP
LW & Java version PRO 4.10.9 & 1.5.0_07
Firewall you're using: Windows Firewall, but its turned OFF
Modem/router brand & model: D-LINK Air DWL 122
ISP: AOL? i'm not sure
Connection type: DSL
Where you connect from: Home
Are you sharing a connection with other computers: Yeah, and both of their Limewires work fine.
Is this your first try with LW: On this computer, yes.

Do this test & post what result you get (does it say "your test worked"?)
http://www3.limewire.com:6346 : Yeah, it says it worked.