Then try deleting LW preferences found here /Users/your_username/Library/Preferences/LimeWire
If still not work, try downlding the newest beta here
Lime Wire ยป Download LimeWire Beta
BTW are you using Java 1.4.2 or 1.5? It's highly recommended to use 1.5 & force LW to use Java 1.5 (
J2SE 5.0 = Java 1.5). You do this by opening the Java utility found in the Utility folder & opening the J2SE 5.0 folder & opening the Java Preferences & putting Java 1.5 at the top of the list. Save your settings of course! More about this here
About Java 2 Platform Standard Edition (J2SE) 5.0 Release 1 for Tiger